COG NEURO EXAM 3

What is the sympathetic nervous system?

"Fight or flight" Blood pressure/heart rate increase, digestive slowing.

What is the parasympathetic nervous system?

"Rest and digest" Blood pressure/heart rate decrease, digestive increases.

Cellular level memory consolidation

-Intrinsic pathways in the hippocampus: -From entorhinal cortex to dentate gyrus to CA3, then to CA 1 -With learning, the synapse among cells in these regions that are responsible for the coded information become strengthened! This is called long -term potentiation (LTP).

LeDoux: slow and fast pathways (5)

-Joseph LeDoux, a very influential emotion neuroscientist has proposed that humans have two emotion systems operating in parallel. -One is a neural system for our emotional responses that bypasses the cortex and was hardwired by evolution to produce fast responses that increase our chances of survival. -The other system, which includes cognition, is slower and more accurate. -(that means the Singer -Schecter and the appraisal theory should be combined.) -slow cogntiion pathway includes emotional feeling (feeling scared) -fast pathway includes defensive behaviors (running way)

Karl Lashley "The Search for the Engram"

-Lashley used experimental lesion to study how brain damage is related to memory lost. -He usually used behavioral learning task, e.g., whether the animal can find the route in a maze. -He concluded that equivalent memory traces are distributed throughout the brain. The amount of the cortex damaged will be related the degree of the memory lost. (Equipotentiality theory! = more tissue lesioned = more difficulty) -As we discussed in chapter 1, in early 20 century, we could not differentiate different types of memory and did not develop methods to measure these different types memory. -But, though the work with H.M. in 1950s and 1960s, we know much better how memory works.

Testing Claims about Primacy and Recency

-The manipulation of working memory should affect the recall of recency items but not items presented earlier in the list. -Delaying recall with a different task displaces content in working memory. -Early items should not be affected because LTM does not depend on the current activity.

Other brain regions and other emotions : Self related processing

-The medial prefrontal cortex is important for social evaluation and self-referencing processing. (Self-reference effect refers to the enhanced memory for information processed in relation to the self.) -medial prefrontal cortex shows stronger activation when we describe something related to ourselves. • In this meta-analysis, Murray and colleagues (2012) combined 23 fMRI and 2 PET studies that compared self-relevant processing against processing of close others and of public figures. They found that the anterior insula is activated when one is appraising and processing information about the self and close others but not about public figures. • This finding led the researchers to suggest that when we appraise ourselves and close others, we share a conscious mental representation that is internal, visceral and actually felt physiologically, know as embodied awareness. • Self-specific processing was found in the ventral and dorsal anterior cingulate cortex, which were not active during the appraisal of close others and public figures.

Orbitofrontal cortex

-The orbitofrontal cortex receive sensory perceptual information from all modalities! It is also connected with the cingulate cortex and ventromedial frontal cortex that send information to the hypothalamus, brainstem and spinal cord. -It plays an important role in reflecting bodily feeling related to emotions and use it in decision making.

How is the brain activated differently when we successfully encode a memory and when we fail to do so?

-We can study this question using neuroimaging methods, and we need to use a "trick": • We first measure the participants' brain activities while they are doing a memory encoding task, e.g., encoding a list of words (or pictures), in the MRI scanner. • After the encoding phase, we will test their memory outside the scanner. We will ask them to identify the pictures they have learned from those they haven't. This way we can know which pictures are successfully encoded and which ones are not. • Then we will go back to the brain activity data collected during the encoding phase to separate the brain activity data corresponding to the subsequently remembered trials (words/pictures) from those corresponding to the subsequently forgotten trials, and then compare the two types of brain activity! This research paradigm is called subsequent memory paradigm.

what are the four types of nondeclarative memory (implicit memory)?

-procedural memory (skills--motor and cognitive). basal ganglia and skeletal muscle is responsible for this memory -perceptual representation system (perceptual priming). perceptual and association neocortex is responsible for this -classical conditioning (conditioned responses between two stimuli): cerebellum -nonassociative memory (habituation, sensitization): reflex pathways

study on amygdala's role in emotion related processes.

-stimuli: trust worthy faces and non trustworthy faces shown -if the face has avg level of trustworthiness, the amygdala shows low activity in neuroimaging, but shows higher activity when the face very high or low trustworthiness the amygdala will show lots of activity.

slide 27 of emotion lecture (anatomy parts)

..

What is the episodic buffer?

Added by Baddely later on (2000) A temporary store- intergrating information from other sub systems rather than seperate strands It's a bridge between working memory and long term memory. Maintains a sense of time recording events (episodes) happening -can handle smell taste, etc

what is the relationship between sensory memory, short term memory and long term memory?

Atkinson & Shiffrin modal model of memory: sensory memory can become short-term memory if it is selected by attention. Then, the short-term memory can become long-term memory if it is rehearsed. E.g., if you repeated a number several times, you may remember the number for a long time.

How about false memory?

Retrieval of true and false memory may elicit activity in the same retrieval networks, but true memories are more associated with greater activity in the medial temporal lobe and sensory areas, whereas false memories are associated with greater activity in the frontal and parietal portions of the retrieval network.

Different stages/phases of memory processing

One way to frame learning and memory: • Acquisition: the process of gaining information and placing it into memory. -Consolidation refers to the process by which memory representations become stronger with time. These two together are called encoding. • Storage: holding the information in memory until it is needed • Retrieval: locating the needed information and bringing it into active use. • This is an analogy to creating, storing, and opening a computer file. • But acquisition and storage can be interconnected, and acquisition and retrieval are also interconnected.

what are interference stumuli?

things that are presented to a participants to interfere with their memory of other stimuli that were shown (helps with testing working memory)

Long and short association connections between different regions

The prefrontal cortex has extensive connections with almost all other regions.

What is the Papez circuit?

The principal pathway of the limbic system, involved in emotion and memory. Hippocampus->fornix->mamillary bodies->mamillothalamic tract->ant thalamus->cingulate->hippocampus.

Dopaminergic system: related to reward and motivation

Ventral tegmental area (VTA) sends dopamine to many brain regions, including the prefrontal cortex, cingulate gyrus, ventral striatum, etc. supporting "wanting" behavior. -important for addiction, motivation, and reward/pleasure seeking

what is a mirror drawing task?

drawing something while only viewing it through a mirror.

Familiarity-Based Recognition Memory

during encoding, as subsequent recognition confidence (confidence in recognition) increases, activity in the perirhinal cortex also increase.

can dorsal prefrontal cortex represent face stimuli?

no but it can send modulatory signals to FFA and other areas and help these areas maintain this info

• Brain Areas Associated With Memory (anatomy)

o Hippocampus o Parahippocampal, entorhinal, and perirhinal cortices (outside the hippocampus) o Amygdala (important for emotional memory/emotional motivation) o Fornix o Mammillary bodies o Medial temporal lobe (MTL) o Anterior thalamic nuclei (part of thalamus)

• Memory retrieval

o Recognition: testing information is presented and participants must decide if it is the sought-after (i.e., previously learned) information. o Example: "Is this the face picture you just saw?" o Source memory: recognizing information accompanied with the original learned information. o Example, after recognizing the previously heard word "book", you will be asked whether you can recognize the voice for the word you heard during the learning phase ("a female or male voice?") o The "remember/know" distinction o Participants may be asked to judge whether a particular item can be vividly recollected ("remember") or if they just had a feeling of familiarity ("know"). o Evidence shows different brain mechanisms supporting for the two types of recognition memory! -Recall memory: participants generates the memory after being given a broad cue identifying the information sought: o Example: "what was the name of the person whose face you just saw?"

• Interference during encoding

o Retroactive interference: newly learned information affects previously learned information. For example, after learning a list (A) of words, you learn another list (B) of words. Compared to no learning of B list, your performance on A list will be reduced. o Proactive interference: early learned information affects later learned information. For example, after learning A and B lists, your performance on B will be reduced, compared to without learning A.

which brain regions shows greater activity when familiarity is high?

parahippocampal gyrus (activity is lower when recognition response is related to recollection and not familiarity)

Theories of Emotion Generation (2)

-According to James -Lange theory, if we do not feel the physiological reactions, the we will not feel the emotion. -However, research findings showed that cats with cortex severed still had emotion reactions. And physiological responses are not necessary or sometimes too slow, to cause emotions or cause different emotions. -Cannon -Bard theory posits that subjective feelings supported by the cortex are separated from the physiological and behavioral responses. So when facing an emotion -provoking stimulus, we will have feelings, at the same time have physiological and behavioral responses.

Theories of Emotion Generation (8) - hierarchical processing theory.

-According to Panksepp, emotion is processed in one of the three ways, depending on which emotion it is. T -he most basics are primary-process or core emotions, which provide our most powerful emotional feelings and arise straight from the ancient neural networks in the subcortex. -Cognition plays no role in this process. -The secondary-process elaborations arise from conditioning (learning). -The tertiary-process emotions are elaborated by cognition.

What is emotion? Anderson & Adolphs (2014) argues:

-An emotion constitutes an internal central (as in central nervous system) state. • This state is triggered by specific stimuli (extrinsic or intrinsic to the organism) • This state is encoded by the activity of particular neural circuits. • Activation of these specific circuits gives rise, in a causal sense, to externally observable behaviors, and to separately (but simultaneously) associated cognitive, somatic, and physiological response.

Cellular level memory consolidation: long-term potentiation

-Bliss and Lomo (1973) found that stimulating the axons of the perforant pathway (axons enter the hippocampus) resulted in a long-term increase in the magnitude of excitatory postsynaptic potentials (EPSPs). -This means the stimulation (like you learn hard the course material) led to greater synaptic strength in this pathway so that the axons were stimulated again later, larger postsynaptic responses resulted in dentate cells. The connection is strengthened, which may reflect the new memory!! In other words, "cells that fire together wire together" (this is Hebb's law). - To create LTP, the stimulation need to be strong enough (we need to learn hard). -There are two types of glutamate receptors on the postsynaptic neuron's dendrites, AMPA-R and NMDA-R. -During weak synaptic signaling, i.e., pre-synaptic neuron fires few action potentials, only AMPA-R will be open. -NMDA-R cannot be opened because it not only needs glutamate, but also needs a significant depolarization of the dendrite membrane potential. -But when a lot of action potentials are generated by the presynaptic neurons, there will be more glutamate release at the terminal, AND the post-synaptic membrane potential will be significantly depolarized. This will activate the NMDA-R. (expels magnesium ion that blocks the channel, see the picture on the next page) -When NMDA-Rs are opened, not only Na+ comes in to the postsynaptic neuron to further depolarize the membrane potential, Ca2+ will also enter the postsynaptic neuron. -Ca2+ will then activate postsynaptic protein kinases, that trigger a series of biochemical reactions. -One is that more AMPA-R will be produced and inserted to the post-synaptic membrane, which leads to the strengthened synaptic signaling! This is one mechanism for LTP. -Intensively learning can also produce a late component of LTP: Ca2+ will trigger another series of changes that eventually turn on expression of several genes that change the synaptic structure (as well as axon structures, astrocytes, vascular structures). -Literally learning changes our brain! Right now, when you learn the information, your brain is change ;)

The ACC and response conflict evaluation

-Cohen and colleagues proposed that the key function of the medial frontal cortex, especially the ACC, is to evaluate response conflict. The reason that high attention demand and error/feedback related processes recruit the ACC may be due to the fact that these situations all involve response conflict. • Consistent with this hypothesis, the incongruent condition of the flanker task and Stroop task, which triggers response conflict, all engages the ACC to a larger extent than the congruent condition of the tasks. • Evidence also shows that after the ACC detects response conflict, it may signal the lateral PFC so that the later PFC can adjust its cognitive control accordingly, e.g., pay more attention to specific aspect of the task, help to inhibit, select, or execute the action/cognition that are more consistent with the goal, etc. • The ACC was also found to evaluate effort associated with a behavioral choice, as mentioned earlier in the exploit/explore trade-off processing. • However, although neuroimaging studies have found the ACC is involved in many aspect of cognitive control, deficits in these aspects of executive function were not found human lesions studies. Therefore, the specific function of the ACC is still under intensive investigation and debate.

Sperling (1960) full report vs. partial report

-In a classic experiment (Sperling, 1960), participants viewed a grid like this one for just 50 ms. If asked to report all of the letters, participants could report just three or four of them. -In a second condition, participants saw the grid and then immediately afterward heard a cue signaling which row they had to report. No matter which row they were asked about, participants could recall most of the row's letters. It seems, therefore, that participants could remember the entire display (in iconic memory) for a brief time, and could "read off" the contents of any row when appropriately cued. The limitation in the report-all condition, then, came from the fact that iconic memory faded away before the participants could report on all of it.

Complex emotions and dimensional theories

-In addition to the 6 or 8 basic emotions, we also experience some complex emotions, such as jealousy, parental love, romantic love, envy, etc. • Complex emotions have longer duration, increase when we become older, may not have universal facial expressions, and fixed behavioral patterns. • Some scientists think we should not group emotions into discrete categories. Even for one basic emotion, it can be different in terms of intensity and can have different behavioral responses in different situations. The so-called different emotions may be just combinations of response along different continuums. • Valence and arousal dimensions: Most researchers agree that emotional reactions to stimuli or events can be characterized by two factors: valence (i.e., pleasant-unpleasant or positive-negative) and arousal (the intensity of the internal emotional response, high - low). • Another dimensional approach characterizes emotions by the actions and goals that they motivate. Some emotions motivate us to approach something (happiness, anger), some motivate us to withdraw from a situation (sadness, disgust).

Valence -arousal model

-In general, this two -dimensional model is widely accepted. Some neuroimaging data seem to support this model. -But we can have two emotions with opposite valences at the same time. -We can study emotion in a laboratory using different methods: 1. Ask participants to see different pictures (accidence scenes, injured body parts, etc.) 2. Ask participants to recall their past emotional events 3. Ask participants to listen to different stories, music, ...

Recollection, Familiarity, and the Medial Temporal Lobe

-Montaldi et al. (2006) in this study, at encoding, participants viewed a series of words and made either an animacy (animate versus not animate) or size (large versus small) judgment for each word, depending on the color of that word (e.g., green font meant to perform an animacy judgment, so for the word NICKEL in green ink, the correct response would be "inanimate"). (This is called an incidental encoding task, whereas in an intentional encoding task we will explicitly ask participants to "memorize" the material.) - Later, in a test at retrieval after the scan session, participants made two decisions about the items presented, which included the old items and new items never seen before. First, participants were asked to indicate whether and how well (how confidently) they recognized the items (e.g., on a scale of 1 to 6, from definitely new to definitely old). Second, for each word, they had to make a source memory judgment (had it previously been presented in red or in green?). Using the successful source memory, the researches can know which items were subsequently recollected, and which were just 'familiar" items. FINDING -Using subsequent memory paradigm, the study found that two regions in the medial temporal lobe that exhibited subsequent recollection effects were the posterior hippocampus and the posterior parahippocampal cortex.

Theories of Emotion Generation (3)

-More recent (contemporary) theories emphasize the role of cognition in emotion generation -how we interpret the stimulus will directly affect what emotion we will experience. -Richard Lazarus proposed a version of appraisal theory in which emotions are a response to the reckoning of the ratio of harm versus benefit in a person's encounter with something. (so basically if risk is high u will get an emotional feeling of being scared and then a behavioral response of running away)

Theories of Emotion Generation (4)

-Other researchers, such as Singer and Schecter, still emphasize the role of physiological response, at the same time accept the important role of cognitive appraisal. -Singer-Schecter propose that emotional arousal and then reasoning are required to appraise a stimulus before emotion can be identified. (you see a bear, then u have a physiological response (arousal) like the heart will race and shit, and then a behavioral response (your run, and then a cognition (think about their situation and decide how they feel), and then an emotional feeling (scared))

Implicit memory tasks

-Participants may study words like bird, house, balloon, horse, rocket ... Then they may be given different tasks: • Lexicon decision task - whether this is a real word: bronk, horse, mouse, (they will respond faster to horse then mouse) • Stem completion task: hor_ _ (they will more likely to make the word "horse" than "horde" • fragment completion task: h_r_s_ (they will more likely to make the word "horse" than "hares" • word association task: saddle - ? "leather" "bags" "horse" (they are more likely to associate saddle with horse) -All these performance patterns reflect implicit memory.

Amygdala and implicit learning (fear conditioning)

-Patients with amygdala lesion (e.g., S.P.) can form explicit memory about their experience, but may not learn emotional (fear) response. • One way to test this is to use fear conditioning paradigm, i.e., pairing conditioned stimuli (blue square) with unconditioned stimuli (electrical shock), then measure their sympathetic nervous system response (e.g., skin conductance changes - sweating). • As shown here, conditioned stimulus did not elicit emotional response in S.P. but did so in normal controls.

Phineas Gage: personality change due to frontal lobe injury

-Phineas Gage is one of the most famous brain injury (penetrating injury) case from which we know the prefrontal lobe (especially the orbitofrontal cortex) is important for personality, social/emotional information processing. • Gage was injured when he worked at a railroad construction site in 1848. An iron rod penetrated his skull. He survived the injury, but he was no longer Gage. • "He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom), manifesting but little deference for his fellows, impatient of restraint or advice when it conflicts with his desires.... A child in his intellectual capacity and manifestations, he has the animal passions of a strong man.... His mind was radically changed, so decidedly that his friends and acquaintances said he was 'no longer Gage." (O'Driscoll & Leach, 1998) • The prefrontal cortex plays a key role in emotion regulation, AND other executive functions.

Theories of Emotion Generation (1)

-Regarding how physiological reaction, behavioral response, and subjective feeling are related to emotion, there are different theories in the literature. -One of the earliest theories is James-Lange theory (James is William James). This theory posits that stimuli will trigger physiological response first, which leads to behavioral response, then we will interpret these responses as the feeling of emotion.

Memory replay during sleep and rest

-Rodent studies have found that the place cells corresponding to the different locations that rats travelled can be replayed during post-learning sleep or rest. -Interestingly, sometimes the neurons replay can be in a reversed order ☺ - Researchers have proposed that the replayed activity may facilitate memory consolidation, i.e., stabilize the newly acquired memory. (sleep is important for memory consolidation. High stress level will kill the hippocampus neurons and lead to memory problems.)

Laterality of frontal activation in memory encoding

-Some frontal and parietal regions, in addition to the MTL and sensory cortex, are also activated in memory tasks. - During memory encoding, words activate left frontal cortex, faces activate primarily right frontal cortex, and nameable objects activate both.

Stress response and hypothalamus

-Stress response may have 3 stages: • Alarm stage: increased sympathetic nervous system activity • Resistance stage: sympathetic response declines; adrenal cortex continues releasing cortisol and other hormones to prolong alertness • Exhaustion stage: occurs after prolonged stress; individual no longer has energy to sustain responses • Stress can activate two response systems in the body • One is the sympathetic nervous system, triggering the "fight or flight" response that prepares the body for brief emergency response. The hypothalamus is the control center of the autonomous nervous system. • The HPA(Hypothalamus-Pituitary-Adrenal cortex) axis may also be activated if the stressor remains. The HPA axis becomes the dominant response to prolonged stressors. -In response to an immediate stressful experience, the nervous system activates the immune system • Increases production of natural killer cells (lymphocytes), leukocytes and cytokines • The cytokines combat infections but also trigger prostaglandins -Prolonged stress produces symptoms similar to depression, can weakens the immune system, and harm the hippocampus • Toxins or overstimulation more likely to damage or kill neurons in the hippocampus • Cortisol also has various physiological effects, e.g., suppression of insulin and immune-inflammatory response, blood sugar or blood pressure increase. Long-term high stress may increase risk of digestive track ulcers, heart disease, hypertension, sleep dysregulation, and psychiatric disorders. -The hypothalamus is the center for the autonomous nervous systems, neuroimmune responses, and many other functions related to sleep, sex, feeding and drinking, body temperature control, aggression, etc. -The other regions in the limbic system, especially the amygdala, have significant influence on the hypothalamus! Therefore, these functions can all be affected by our emotions!

The vlPFC (ventro lateral prefrontal cortex) and goal -related selection STUDY

-The lateral prefrontal cortex may also help us to select or filter information related to the current goal o For example, studies have found that vlPFC is involved in fluency tasks, in which participants need to generate words semantically associated with a cue word. o In another fMRI study, researchers varied the demands on a filtering process during a verb generation task. In a low -filtering condition, participants were asked to name actions that go with words with fewer associated verbs (e.g., scissors). But in a high -filter condition, they need to name actions that go with words with many associated verbs (e.g., rope). Stronger activation was observed in the left vlPFC and temporal lobe regions. FINDING o The study also found the involvement of the vlPFC and temporal regions were different: o The vlPFC involvement was stronger whenever a generation/selection demand was higher no matter whether the semantic information was repeated. But the temporal regions showed decreased activation when the semantic information was repeated. o These results suggest that the vlPFC may help to generate and select semantic information supported by the temporal lobe. o This is similar to the role of the dlPFC (dorsolateral prefrontal cortex) in working memory processing: it helps to maintain and manipulate working memory, but the WM representations may be supported by other regions. ANOTHER STUDY • In another neuroimaging study (Dux et al., 2009), participant were asked to intensively practice a visual -manual task (e.g., press one of two buttons to indicate the position of a stimulus) and an auditory -vocal task (e.g., say different sounds to different auditory stimuli) task. They practiced the two separately (single task) and together (multitasking). FINDING • The researchers found that the connectivity between the vlPFC with the sensory and motor regions related to each task remained strong and task specific before and after the training, indicating that the vlPFC may help to select the response based on the stimuli. • (Dux et al., 2009) More interestingly, before the training when participants did the two tasks together (i.e., the multitasking condition), the vlPFC was engaged in a longer time period compared to the single task condition; however, after the training, this region showed the same level of engagement (in terms of time length) in the single and multitask condition. • The results suggest that with practice, the involvement of the vlPFC may become more efficient in helping switching between the two tasks.

Neural Systems Involved in Emotion

Early Concepts • James Papez • Hypothalamus, anterior thalamus, cingulate gyrus, and hippocampus Emerging Concepts • Somatosensory cortex • Higher-order sensory cortices • Thalamus • Amygdala • Insula • Hypothalamus (and some brainstem structures) • Ventral striatum • Medial prefrontal cortex • Orbitofrontal cortex • Anterior cingulate cortex (ACC)

Theories of Emotion Generation (7)

Emotion as central causative states: Anderson and Adolphs argued that an emotional stimuli activates a central nervous system state that in turn simultaneously activates multiple systems producing separate responses: feelings, a behavior, a psychophysiological reaction, and cognitive changes.

why is memory important?

Memory is the central for everything we do, jobs, school, etc. literally cant do anything without memory (gives us expertise)

Theories of Emotion Generation (6)

Evolutionary psychologists (e.g., Cosmides Tooby) propose that emotion is not reducible to its effects on physiology, behavioral inclinations, cognitive appraisal, or subjective feelings. Instead, emotions are conductors of an orchestra of cognitive programs that need to be coordinated to produce successful behavior to aid survival.

Other brain regions and other emotions: Empathy

Neuroimaging studies have found when seeing their rival team failed, participants' ventral striatum showed stronger activity, whereas when their favored team failed or rival team succeeded, the ACC (anterior cingulate cortex) and insula were more activated.

Explaining Recency and Primacy

Recency effect • Last few items in the list are still held in short-term (or working) memory • Earlier items are displaced by subsequent items • Primacy effect • Memory rehearsal • As the list progresses, attention is divided across more items and less is devoted to each individual item. • Words later in the list are rehearsed less than earlier items. • Rehearsal increases the chance there will be a transfer of items from working memory to LTM. • Earlier items were rehearsed more, so there is a greater chance of transfer.

What is emotion?

We all feel emotions! But it is not very easy to define emotion scientifically. This may be due to a couple of reasons. • We have different emotions, such as fear, sadness, happiness, disgust, surprise, etc. Some may be very complex, such as love, remorse, envy, etc. • There are different components for each emotion, such as subjective feeling, bodily response, actions, thoughts, regulations, etc. • Animal research findings may not be directly translated to humans, because we live in a much more complex social environment and have more complex cognitions. But ideally we want a definition that can be used for all species (who have emotions). • At the behavioral level, it is not easy to construct a definition that can be precise and comprehensive at the same time. • In the brain, we are still in the process of revealing the neural mechanisms of emotions.

what is a behavioral response?

an action (running away after seeing a bear)

What is the James-Lange theory of emotion?

an event occurs/stimulus (seeing bear), you have a conscious perception of a stimulus, then u have a physiological response, then a behavioral response then a cognition and then a subjective emotional feeling.

what is a cognition?

automatically and nonconsciously interpreting u physiological response (my heart is beating fast and im running so im must be afraid)

why did baddeley's model of workin memory evolve?

because the earlier model did not show how we can integrate different modalities. -new one added episodic buffer (integrates between modalities)

Who is Clive Wearing?

cannot form new memory due to viral infection (the Man has 7 second memory)

What are place cells?

cells that respond only when an animal is in a particular place in a familiar environment -found in hippocampus

what are the two types of declarative memory?

episodic (events) and semantic (facts)

what is the other name for declarative memory?

explicit memory

how did HM perform on mirror drawing?

he couldn't remember doing the tasks but he physically improved (showed that he can learn new skills even tho he couldn't form new memories)

wat is the control center for sympathetic nervous system?

hypothalamus

what is a subjective emotional feeling?

im scared

what is the other name for nondeclarative memory?

implicit memory

what does the route into memory look like?

incoming info into sensory memory and then in short term memory, and if you maintain and rehearse that short term memory it wont be lost and will become a part of long term memory (long term memory is retrieved from short term memory)

what is a psychological response?

increase in heart rate, release of adrenaline, sweating (this could be in response to seeing a bear)

what is episodic memory?

information about events we have personally experienced

what brain regions are responsible for declarative/explicit memory?

medial temporal lobe, middle diencephalon, and neocortex

hippocampus is more important for _____ while amygdala is more important for ______

memory, emotion (however they both interact)

which brain region shows higher response when recollection is high?

the bilateral hippocampus

What is the endowment effect?

the tendency of people to be unwilling to sell something they already own even if they are offered a price that is greater than the price they would be willing to pay to buy the good if they didn't already own it

can stress kill hippocampal cells?

yes

do humans have a larger prefrontal cortex compared to other animal?

yes

if you slow down the time in which words are presented, will that increase rehearsal?

yes thus its better for primacy effect

H.M.

• A very (probably the most) famous case in medical science is a patient with a memory disorder, who is H.M. (Henry Molaison). • H.M. had serious epilepsy when he was young. In his twenties, he received a surgery which had part of his temporal lobes, including his amygdala, entorhinal cortex, and hippocampi removed. • The surgery succeeded in treating H.M.'s epilepsy, but caused profound amnesia • He can remember his personal history, facts he had learned in school, language, how to do things, social events, people, almost everything - up until a couple of years before his surgery. • He lost memories for those previous couple of years prior to the surgery. • More troubling was he could not form new memory! • H.M. was studied extensively by neuroscientists, psychologists, and neuropsychologists in late 1950s, then 1960s, 70s. These studies significantly improved our understanding of memory. • From H.M., scientist know that the hippocampus plays a key role in episodic memory processing. • From H.M., scientists further confirmed that there are different forms of memory, because not all H.M.'s memories were impaired.

Stress and memory

• Acute stress may facilitate memory • There is a close interaction between the amygdala and other structures of the medial temporal lobe, including the hippocampus, entorhinal cortex, etc. • Chronic stress may impair performance of the hippocampal memory system. • Prolonged stress can kill hippocampal neurons.

Emotion: Related concepts

• Affect is either a discrete emotion that has a relatively short duration or a defuse, long lasting state such as stress or mood. • Stress is fixed pattern of physiological and neurohormonal changes that occur when we encounter a stimulus, event, or thought that threatens (or we expect it will threaten) us in some way. • can lead to activation of sympathetic nervous system's fight-or-flight responses • can also lead to the activation of the HPA (hypothalamic-pituitary-adrenal) axis and release stress hormones, such as cortisol, which can have many effects on the body (increasing blood glucose levels, decreasing inflammatory responses, suppressing immune system functions, etc.) • Mood is a long lasting diffuse affective state that is characterized by primarily a predominance of enduring subject feelings without an identifiable object or trigger. • Low intensity, long lasting, • Neural substrate of different moods are still poorly understood.

H.M.'s brain

• After H.M. passed away in 2008, his brain was cut to thousands of thin slices and preserved. • As can be seen in the picture here, lesions occurred in the medial temporal lobe regions (a and b) and in an orbital frontal region. • The hippocampal lesion can be seen in figure below (figure g)

Amygdala's role in other emotion related processes

• Amygdala damage affects the ability to recognize facial expressions of fear or disgust. One reason is the patient failed to look at the eye regions of the face expressions. For fear, eye whites convey the crucial information! (SM often avoided looking at the eyes but when u tell her to look at eyes she can identify the facial emotion properly) -Although patients with amygdala lesions usually do not show gross impairment in their ability to respond to social stimuli (not as serious as lesions in the orbitofrontal cortex), they can have some level of impairment in social stimulus processing • They have difficulties in perceiving or interpreting emotion and sociability in inanimate objects (a "cute" cup). • They may have difficulties in regulating personal space with others. • The amygdala also appears to be activated during the categorization of people into groups or processing animate stimuli. Studies have found white participants' amygdala showed stronger activity when they viewed black, than white, faces, especially when the faces were presented very briefly (i.e., relying more on quick automatic evaluation). -Quick evaluation of black vs. white faces led to stronger amygdala activation. -Similar results have been found when categorizing sex and coalition affiliations. -These results indicate the social or affective value of face stimuli may engage the amygdala.

The ACC and attention control

• An early hypothesis on the ACC function is that the ACC is part of an attentional hierarchy, playing a critical role in coordinating activity across attention systems. • This system ensures that processing in other brain regions is as efficient as possible, given the current task demands. Interactions with the prefrontal cortex may select working memory buffers; interactions with the posterior cortex can amplify activity in one perceptual module over others. The interactions with the posterior cortex may be direct, or they may be mediated by connections with the prefrontal cortex

Auditory sensory memory

• An event-related potential (ERP) known as the electrical mismatch negativity (MMN), or its magnetic counterpart (using MEG), the mismatch field (MMF), has been used to measure echoic memory. • MMN/MMF responses are elicited by the presentation of a rare deviant stimulus, such as a high-frequency tone, presented within a sequence of identical and more commonly presented low-frequency tone. • Two conditions: standard stimulus vs. deviant stimulus • Then the ERP corresponding to the two conditions can be compared. The ERP component shows the difference is called mismatch negativity • Then, the researchers manipulated the interstimulus interval to see after how long this MMF will disappear, i.e., the sensory memory for the previous trial will not have effect (i.e., decayed). • As can be seen here, the amplitude of the MMF (indicated by the shaded difference between the blue and red traces) declines as the time between the preceding standard tone and the deviant tone increases to 12 seconds. • The result can be interpreted as evidence for an automatic process in auditory sensory (echoic) memory that has a time course on the order of approximately 10 seconds.

Anterior Versus Posterior System

• Anterior temporal system includes the perirhinal cortex and its connected areas such as anterior hippocampus, amygdala, ventral temporal pole area (vTPC), and lateral orbital frontal areas. This system is responsible for item memory or familiarity based memory. • Posterior temporal system is composed of parahippocampal area, RSC, mammillary bodies, anterior thalamic nuclei, and others. This system is responsible for scene memory or recollection based memory

what are the different types of amnesia?

• Anterograde Amnesia: the lost of the ability to form new memories • Retrograde Amnesia: the lost of memory for events that happened in the past. • Temporal Limitations: retrograde amnesia following brain damage that extends backward from the time of the damage but does not include the entire life of the affected individual. • Sometimes the retrograde amnesia can extend back to only a few minutes or hours, and sometimes can extend back to a few years. • Temporal Gradient (Ribot's Law): refers to the phenomenon that retrograde amnesia tends to be greatest for the most recent events. Also called Ribot's law, proposed by Ribot in 19th century.

Parietal involvement: the retrosplenial cortex

• As discussed before, parietal lobe regions are important for attention. Usually parietal lobe lesions may not course serious memory problems. • One region in parietal lobe, the retrosplenial cortex (RSC), is important for memory processing. Lesion of this region may cause both retrograde and anterograde amnesia. • RSC is extensively interconnected with the parahippocampal cortex and interface with other regions in the MTL (hippocampus, anterior thalamus, and mammillary bodies).

The ACC and error detection

• As discussed earlier, we can examine the brain activity whenever participants make a mistake in a go/nogo or Stroop task, or other tasks (as the one shown here- Eriksen Flanker task), or when they receive a feedback. • When using EEG/ERP method, scientists have found specific ERP components that reflect the error- or feedback-related processing, called error-related negativity (ERN) and feedback related negativity (FRN). These components was found from the electrodes located in the frontal medial part of the scalp and likely generated from the ACC. (Gehring lab at UM) • The ACC was also involved when we need to effortfully monitor our performance. E.g., in the stroop task, we have to monitor whether we indeed name the ink of the color words, not the words themselves. • Using ERN measure, scientists also found that the ACC is also more active when we receive unexpected feedback, not just when making errors

The OFC/mPFC and value representations

• As mentioned earlier, different factors may affect how we, or other animals, assign values to specific object or event, such as the payoff itself, the probability, or effort of obtaining it. • To investigate how the brain represents the different aspect or dimension of values, Kennerley et al (2009) used multiple electrodes to record from cells in three regions: the anterior cingulate (ACC), the lateral PFC, and the orbitofrontal cortex (OFC). • They found that all the three regions included cells that responded selectively to a particular dimension, as well as cells that responded to multiple dimensions. • But they also found many cells in the ACC responded to all 3 dimensions, meaning that they are important for supporting all aspects of value processing. The LPFC cells, however, usually encoded just a single decision variable, with a preference for probability. The OFC cells had a bias to be tuned to payoff, reflecting the amount of reward associated with each stimulus item. -Human neuroimaging studies also found that the OFC activation was closely tied to variation in payoff, whereas activation in the striatum of the basal ganglia was related to effort (Corxson et al., 2009). • Similarly, another neuroimaging research found that the LPFC was associated with the probability of reward, whereas the delay between the time of the action and the payoff was correlated with activity in the medial PFC and other regions. • Temporal discounting is the observation that the value of a reward is reduced when we have to wait to receive that reward. • Patients with OFC lesions showed abnormal temporal discounting compared to patients with lesions outside the OFC or healthy controls. Specifically, OFC patients were not willing to wait longer for a larger reward, for which, for example, normal controls would. This indicates the OFC and vmPFC is important for supporting value processing and related decision making -Human neuroimaging studies also found the OFC (more of the vmPFC) activation is associated with taste preference, regardless of whether the item was healthy. • In contrast, the LPFC (i.e., vlPFC) was associated with the degree of control, showing greater activity on trials in which a preferred but unhealthy item was refused, as compared to trials in which the item was selected. (vlPFC : selection!) • Therefore, the vmPFC and OFC plays a key role in the representation of value. • Very often the situation in which we need to make a decision is ever evolving and dynamic. We may need to constantly evaluate whether we should stay with the same choice or it is time to explore new possibilities for a better outcome (For some people, finding a job or partner can be a good example ☺ ). • In decision making science or behavioral ecology, especially related to foraging behavior (finding food or other valuable resources), "exploit" refers to the behavior that continues to accept or take advantages of familiar options with known or diminishing reward, and "explore" refers to trying unfamiliar options for unknown rewards (can be larger or smaller or none). Very often we need to deal with the explore/exploit trade-off. • To test which brain region plays a key role in deciding the transition from exploit to explore, Hayden and colleagues trained monkeys to do exploit/explore trade-off task. • Specifically, after fixation, two eccentric targets, a large gray and a small blue rectangle, appear. Monkey chooses one of two targets by shifting gaze to it. Choice of blue rectangle (stay in patch) yields a short delay (0.4 s, handling time) and reward whose value diminishes per trial. Choice of gray rectangle (leave patch) yields no reward and a long delay (travel time) and resets the value of the blue rectangle. • They found the ACC activity signaled the transition from exploit to explore! When the ACC neuronal firing rate reach the threshold earlier, the monkey will leave the current option earlier! • Human neuroimaging studies (e.g., Kolling et al., 2012) also found that the ACC plays a role in the exploit/explore trade-off: its activation correlates positively with the explored value and negatively with the exploit value. It may code the value of switching to a course of action alternative to that which is taken or is the default (value-guided response selection). It facilitates the exploration of the environment for better alternatives compared to the current course of action. • The vmPFC however, was found to encodes the value of chosen or attended options in comparison with unchosen or unattended options (comparing values). • Similarly, another neuroimaging study found that the vmPFC activity (very often the textbook treats the vmPFC as OFC. It is better to differentiate them) is positively correlated with positive affect (green) when making a choice, whereas the ACC activity is correlated with high level of anxiety. • The reason the ACC was involved in the high anxiety situation where one of two high value items needs to be selected may be that this region supports value-based selection of response.

Which brain region supports procedural memory?

• Basal ganglia may play a key role in supporting habit learning! (remember the corticostriatothalamal circuit discussed in the Motor chapter?) • To test this hypothesis, researchers trained rats to take turn in a T -maze according to auditory cues which indicated where (left or right) the reward was located. After the rats were overtrained, they were put into extinction session in which the reward was either withheld or placed randomly. • Then the rats were retrained. • This experimental design allow scientists to examine neural activity in the basal ganglia during the initial skill acquisition, extinction, and re -acquisition phases. -The data indicate that as training progressed to an overtrained stage, the firing of basal ganglia neurons strengthened at the start and end of the learned procedure, whereas activity in the task-unresponsive neurons fell silent. A reversal of this pattern occurred in extinction. -Basal ganglia patients also have difficulties in learning new motor skills.

Categorizing emotions: Basic emotions

• Basic emotions refers to a closed set of emotions, each with unique characteristics, carved by evolution and reflected through facial expressions. • This categorization is largely based on the nativistic (innate) view. A specific type of stimuli will robustly trigger a specific type of basic emotion (such as fear, disgust, sadness) in both humans and animals. • Studies have found that electrical stimulation of specific locations within specific subcortical brain regions produced very specific emotional behavioral patterns. • E.g., Panksepp selectively activated rage, fear, separation distress, and generalized seeking patterns of behavior by stimulating different bran regions. • According to Panksepp, there are seven primary-process emotional systems, or core emotional systems, produced by ancient subcortical neural circuits common to all higher animals. • SEEKING/desire system, RAGE/anger system, FEAR/anxiety, LUST/sex, CARE/maternal nurturance, GRRIEF/separation distress, and PLAY/physical social engagement.

Cognitive control or executive functions

• Cognitive control is "the process that allows information processing and behavior to vary adaptively from moment to moment depending on current goals, rather than remaining rigid and inflexible" http://carterlab.ucdavis.edu/research/control.php (facilitate goal-directed behavior/not aimless behavior) • Cognitive control is very complex, relying on many different types of executive functions. E.g., when we try to execute goal-directed behaviors, we may need to: • maintain the goal, or goal-related stimuli/context information in mind (working memory) • pay attention to different stimuli or aspects of the goal/context (attention control) • be able to inhibit behaviors/thoughts/emotion incompatible with the goal (inhibitory control). • make plans regarding how to achieve our goals (planning, strategy use) • make decisions when we have different options/plans (decision making) • monitor our behavior or performance to make sure it is consistent with our goals (monitoring, conflict resolution). • be flexible: changing behavior/plan/attention/decision when necessary (flexibility) • follow rules or make rules, related ideas, retrieve memories ... • We have discussed the attention control network, e.g., the dorsal and ventral attention network, which involves the frontal and parietal lobe. • In general, the frontal lobe, especially the prefrontal cortex, plays a key role in supporting cognitive control, or executive functions, including but not limited to: • Working memory • Inhibitory control • Planning • Decision making • Performance/conflict monitoring • Information updating • Multitasking ...

Amygdala and fear conditioning

• Conditioning: CS (conditioned stimuli) paired with US (unconditioned stimuli) (trigger UR (unconditioned response)), then CS will cause CR • During extinction, CS will not be paired with US anymore, eventually CS will not cause CR • Extinction is not the reverse of the original fear learning. It is a new learning (needs the prefrontal cortex!). • Fear response can return after a period of time (spontaneous recovery). • Can return in a new context (contextual renewal) • Quickly return when re -exposed to US (reinstatement) -prefrontal also important for emotion • The amygdala plays a key role in fear conditioning. Using single cell recording, scientists, e.g., from Joseph LeDoux's group, found that neurons in the superior dorsolateral amygdala have the ability to rapidly pair the CS to the US. • After several trials, cells in the inferior dorsolateral regions took over to maintain the adverse association. • The lateral nucleus send projections to the central nucleus, which eventually trigger emotional responses, through connections with other regions in the limbic system, such as the hypothalamus, brainstem nuclei, etc.

Memory Consolidation

• Consolidation is the process that stabilizes a memory over time after it is first acquired. • How can we know consolidation occurs? • Ribot's law: retrograde amnesia tends to be greatest for the most recent events. • Patients who have undergone electroconvulsive therapy to treat psychological disorders were also found to lose memory acquired close to the time of the treatment. • Consolidation processes occur at the cellular level, as well as at the system level .• System level consolidation is related to how brain regions change when memory becomes consolidated. • Standard consolidation theory, proposed by Larry Squire and colleagues, considers the neocortex to be crucial for the storage of fully consolidated long-term memory, where as the hippocampus plays only a temporary role. • According to this theory, the representations of an event that are distributed throughout the cortex come together in the medial temporal lobe, where the hippocampus binds them. • Consolidation occurs with time in which the hippocampus helps the cortex itself to connect the information from the event and hippocampus becomes less and less important. • Multiple trace theory, by Lynn Nadel and Morris Moscovitch, suggests that the reason that the hippocampus is not important for consolidated memory is that the original detailed episodic memory becomes gist-like semantic memory, which is supported by the neocortex. If you need to retrieve vivid detailed episodic memory, the hippocampus is always needed. More and more data support this theory.

Human Long-term Memory

• Declarative long-term memory: also called explicit memory, including the world knowledge or personal experience to which we have conscious access • Episodic memory: comprises memories of events that the person has experienced that include what happened, where it happened, when, and with whom. It differs from personal knowledge. • Autobiographical memory can contain both personal knowledge and episodic memory. • Episodic memory is the result of rapid associative learning in that the what, where, when, and who of a single episode (i.e., the context) become associated and bound together. • Semantic memory is objective knowledge that is factual in nature but does not include the context in which it was learned. • The differentiation between episodic and semantic memory was proposed by Tulving. Evidence showed that different brain regions support the different type of memory

Alzheimer's Disease

• Dementia: a loss of cognitive function in different domains beyond what is expected in normal aging. This is a type of neurodegenerative disease. • Alzheimer's disease contributes to 60% -70% of dementia cases, which is characterized by amyloid plaques and neurofibrillary tangles, especially in the medial temporal lobe, causing significant memory loss and cannot form new memory! • Vascular dementia is the second most common type of dementia, making up 15% of dementia cases. • Lesions that damage the lateral cortex of the anterior temporal lobe but do not extend to the hippocampus, such as those associated with some forms of frontotemporal lobar degeneration and herpes simplex encephalitis, can lead to severe retrograde amnesia for semantic memory but not episodic memory. • This double dissociation indicates the hippocampus is important for episodic, but anterior temporal pole for semantic, memory.

Classical conditioning, habituation, and sensitization

• Different brain regions may be involved in different types of classical conditioning. For example contextual fear condition (e.g., associating a maze with foot shock) may require both the hippocampus and amygdala. Trace condition in which there is a time gap between conditioned and unconditioned stimuli also requires the hippocampus. Some conditioning task may involve the cerebellum. • Habituation and sensitization are considered as nonassociative learning. They may be supported by the sensory and sensorimotor pathways, which may also be modality dependent.

Hippocampus: binding of item and contexts

• Different types of information from all over the cortex converge on the medial temporal lobe regions surrounding the hippocampus, but not all types pass through the same structures. • Information about the features of items ("what" an item is) coming form unimodal sensory regions of the neocortex passes through the perirhinal cortex (anterior portion of the parahippocampus). Information form multimodal neocortical areas about "where" something is located passes through the more posterior part of the parahippocampal cortex. • Both information then projects to the entorhinal cortex and then converges in the hippocampus. This is called binding of item and context model. • The hippocampus is also important for supporting relational memory - relating information A with information B (remembering people)

Emotion effects on other cognitive processes

• Emotion can affect perception and attention. • For example, if two stimuli are presented rapidly in sequence, the second one may not be perceived. This is called attentional blink. However, if the second stimulus is emotional salient (having arousal value), participants can overcome the attentional blink. • So when attentional resources are limited, arousing emotional stimuli are easier to reach awareness. • It is likely that early in the perceptual processing, the amygdala receives input about its emotional significance and, through projections to sensory cortical regions, modulates the attentional and perceptual processes. • Evidence shows that connectivity between the amygdala and visual perceptual processing regions was enhanced for emotional stimuli (especially presented subliminally). • The amygdala, as well as early sensory regions, is more responsive to novelty stimuli, socially significant stimuli, e.g., faces (so does the hippocampus). • Emotion can affect decision making processes. • Somatic marker theory: it posits that when we make a decision, physiologicalemotional responses, as somatic marker, may provide common metrics for evaluating options with respect to their potential benefits. • One brain region that is crucial for providing this somatic marker is the orbitoprefrontal cortex (OFC) and ventromedial prefrontal cortex (vmPFC). These regions use the physiological responses elicited by emotion to facilitate decision making processes. • This theory is proposed by Damasio (1996) and colleagues and motivated a lot of studies a decade ago. There is also evidence inconsistent with the theory. • There are two primary ways by which emotion influences decision making: • Incidental affect: current emotional state, unrelated to the decision at hand, incidentally influences the decision; • Integral emotion; emotions elicited by the choice options are incorporated into the decision.

Amygdala, arousal, and modulation of memory learning

• Emotion can enhance memory: we usually have better memories of emotional salient experience, e.g., first kiss, tragic events, weddings, etc. • Studies on emotional memory found that an arousal response (related to amygdala) can influence people's ability to store declarative or explicit memory. • Using water maze task, if a rat with a normal amygdala is aroused, by a physical stressor or drug, immediately after training in the water maze, then the rat will show improved retention of the task. (keep in mind that in a normal situation, the amygdala is not required for rats to learn water maze task. Instead the hippocampus is needed. But the amygdala supports the arousal enhancement effect on learning!) • Studies with humans also found the amygdala can enhance retrieval of emotional memory (patient study) and the amygdala showed stronger activation or stronger connectivity with the hippocamps when retrieving emotional stimuli. • The arousal-dependent modulation of memory can occur after initial encoding of the task, during the retention interval. Therefore, this amygdala mediated memory enhancement is related to memory consolidation. • Synaptic tag-and-capture theory: new memories that are initially weak and unstable but occurred close to emotional events can be tagged for later stabilization, i.e., consolidation. This can explain why some trivial events before or after an emotionally salient event can be remember very well. • To test this theory, researchers showed participants pictures from two categories: animals and tools. Then pictures from one category were paired with electrical shock. Researchers found that participants' memory was better not only for the images that were associated with shock in the conditioning phase, but also for images from that same category that were shown only in preconditioning phase but not associated with the shock!

Carroll Izard (1923-2017), who is an influential psychologist in emotion research, summarizes emotion like this:

• Emotion consists of neural circuits (that are at least partially dedicated), response systems, and a feeling state/process that motivates and organizes cognition and action. Emotion also provides information to the person experiencing it, and may include antecedent cognitive appraisals and ongoing cognition including an interpretation of its feeling state, expressions or social-communicative signals, and may motivate approach or avoidant behavior, exercise control/regulation of response, and be social or relational in nature. (Izard, 2010).

what is emotion generally defined as?

• Emotion is an affective (positive or negative) mental response to an external stimulus or internal stimulus or representation that consists of a physiological response, behavioral response, and a feeling (e.g., change in heart rate, jumping back, and feeling scared). • Involve changes across multiple response systems (e.g., experiential, behavioral, physiological) • Are distinct from moods, in that they often have identifiable objects or triggers • Can be unlearned responses to stimuli with intrinsic affective properties (e.g., smiling after your very first taste of sugar), or learned responses to stimuli with acquired emotional value (e.g., fear when you see a dog that previously bit you) • Can involve multiple types of appraisal processes that assess the significance of stimuli to current goals • Depend on different neural system

Cognitive control of emotion: Emotion regulations

• Emotion regulation refers to the processes that influence the types of emotions we have, when we have them, and how we express and experience them. It is a very important skill since we all need to regulate our emotions. • The emotion regulation processes can intervene at multiple points during the generation of emotion, some early on and some after the fact. -model of cognitive control processes: situation selection, situation modification, attention deployment, cognitive change (appraisal --aversive or appetitive, and response modulation. -Antecedent-focused (reappraisal) vs. response-focused (suppression) emotion regulation (Gross's model) • Studies have found both reappraisal and suppression can reduce emotion-expressive behavior when watching a disgust-eliciting film, only reappraisal actually reduced the disgust experience. Suppression increased sympathetic activation. • Neuroimaging studies found using reappraisal to regulate emotion recruited the prefrontal cortex and dampened the amygdala activity. (Ochsner et al., 2002). STUDY • In this fMRI study (Ochsner et al., 2004), the researchers examined brain activity related to downregulating negative emotions (making a bad situation better) vs. upregulating negative emotions (making a bad situation worse). • They asked participants to look at negative images. Then they divided the participants into two groups: • In a self-focused group, participants were instructed to imagine themselves or a loved one in the negative scene (upregulation); in a detached way (down regulation), or, in a control condition, simply to look at the image • In the situation-focused group, participants were told to increase emotion by imagining that the situation was becoming worse, or to decrease emotion by imagining it was getting better, or again just to look at the image. FINDINGS • The researchers found that when the negative emotion was enhanced or reduced, the left PFC and dorsal anterior cingulate were engaged, suggesting that these regions were involved with evaluating and deciding the cognitive strategy. • When participants downregulated their negative emotion, the lateral PFC was engaged, which may play a role in inhibiting the emotion. • When participants upregulated their negative emotion, the left rostromedial PFC and the posterior cingulate cortex were active, which may be implicated in the retrieval of emotion knowledge. • The important point is different part of the PFC may support different strategies in emotion regulation. • But the amygdala was more active when the goal is to enhance the negative emotion STUDY • When doing a risk-taking task, some older people can control very well their negative emotions so that the task, especially in those "loss" trials, will not make them have a lot of feeling of regret (healthy), compared to those older people who cannot control their emotion very well ("depressed") or young adults. This study found that the anterior cingulate was more activated for those healthy older adults than those 'depressed" older adults or young adults in this situation. FINSDING • This study concluded that responsiveness to regret was reduced in successful aging paralleled by this frontalstriatal activation pattern, indicating adaptive shifts in emotion regulation.

• Implicit memory (vs. explicit memory)

• Implicit memory is the memory we are not consciously aware of and can only be measured using indirect memory testing, such as priming • Priming: refers to a change in the response to a stimulus, or in the ability to identify a stimulus, following prior exposure to that stimulus. E.g., you are presented a cat picture very briefly and you cannot even recognize the image, but you are more likely to mention "cat" when you are asked to list a few animals. • Priming effect can be modality specific: visual information leads to visual priming not auditory. Priming effect can be short but also last very long. • There are different types of priming: perceptual priming, conceptual priming, and semantic priming

Short- and Long-Term Memory: primacy and recency effectso

• Participants study a long series of words (e.g., 30 words, 1 word presented per second) • Free-recall memory test • Primacy effect • Better memory for first few items relative to middle items • Recency effect • Better memory for the last few items • Last few items are not displaced by future items

Dorsolateral prefrontal cortex and working memory

• Evidence showing the prefrontal cortex is important for working memory: o Human neuroimaging studies (e.g., fMRI) also found the activation in the dorsal lateral PFC increased with working memory load (e.g., more faces need to be kept in working memory). o Similar activation pattern was found in the posterior perceptual regions, i.e., the fusiform face area. o It suggests that the lateral PFC may help to sustain representations of task goals/stimuli by working in concert with other brain regions. o To what extent the PFC itself represents the information or supports other regions to represent the information is still in debate. • Evidence showing the prefrontal cortex is important for working memory: o Using the n-back working memory task, neuroimaging studies also found that activation in the lateral PFC increase as nback task difficulty is increased. o In n-back tasks, the working memory information not only needs to be maintained in each trial, but also be updated constantly. o The results also suggest that this brain region is crucial for working memory manipulation or operation, not static maintenance. • Evidence showing the prefrontal cortex is important for working memory: o Using the n-back working memory task, neuroimaging studies also found that the dorsolateral PFC network expands, showing marked connectivity with parietal, temporal, and visual regions, which reinforces the idea that the PFC may work with other regions to support working memory processing

Dorsolateral prefrontal cortex and working memory

• Evidence showing the prefrontal cortex is important for working memory: o Neuroimaging studies have also show that when a simple rule (simple stimulus response mapping) is maintained in working memory, the ventral PFC and premotor cortex are involved. But when the rule becomes more complex (more stimulus-response mappings), more anterior regions in the PFC will be involved. o Together with other evidence, it has been proposed that more anterior regions along the rostro-caudal axis of the frontal cortex support rule learning at higher levels of abstraction.

Baddeley's working memory model

• Evidence support Baddeley's working memory model: phonological loop • You can memorize more shorter words then longer words give the same amount of time. • When participants recalled strings of consonants, although the letters were presented visually, participants' error showed that they used an acoustic code, because they were more likely to replace a presented letter with an erroneous letter having a similar sound (e.g., T for G). • When participants were asked to remember a list of words, when the words sound similarly, the performance was poorer, because the acoustic code interfered with each other. • Digit span task is often used to test this type of working memory: • Digit-span task: participants hear a series of digits read to them (e.g., "8, 3, 4") and must immediately repeat them back. The list is increased until memory fails. The number of digits the person can echo back without errors is referred to as that person's digit span

Baddeley's working memory model

• Evidence support Baddeley's working memory model: visual spatial sketch pad. • When we are trying to maintain a list of words in our mind, and at the same time doing a visual spatial task, our later word recall performance will be less affected compared to if we are doing a verbal task, and vice versa. This indicates there are two different systems: the interference is stronger within the system than between the system. • Spatial span task:

H.M.'s brain

• H.M. retained all knowledge about the world (semantic memory) that he had learned in his life up to the 2 years immediately before his surgery. • Form those 2 years forward, he could remember nothing. (retrograde amnesia with temporal gradient) • He also showed selective memory loss for personal event (episodic memory) as far back as a decade before the surgery.. • He had normal short-term memory (including sensory memory and working memory, e.g., digit span) and procedure memory (such as how to ride a bicycle, tie his shoes, play a game). • He cannot form new long-term episodic memory (severe anterograde amnesia) but can still learn procedural skills. • This dissociation between short-term vs. long-term memory, between procedural/semantic and episodic memory, significantly advanced our understanding of human memory (multiple components/forms and supported by different brain structures!). The hippocampus is important for supporting episodic memory.

Other brain regions and other emotions: happiness

• How the brain support positive emotions, such as happiness and love? • Habel et al (2005) compared participants brain activity when they were induced sad or happy mood. They found that sad and happy moods produced similar activations in the amygdala-hippocampal area (including other medial temporal lobe regions), the prefrontal and temporal cortex, anterior cingulate etc. • They also found happiness produced stronger activations in the dorsolateral prefrontal cortex, cingulate gyrus, inferior temporal gyrus, and cerebellum. • When watching love-related stimuli, brain regions related to reward, motivation, emotions, and cognitions will be activated. These regions usually include the dopaminerich area such as the insula, caudate nucleus, ventral tegmental area, anterior cingulate, and hippocampus, etc.

Executive functions: Decision making

• How we or our brain computes value and processes rewards? • Primary and second reinforcers: Primary reinforcers: the rewards such as food, water, or sex, that have a direct benefit for survival fitness. Secondary reinforcers: The rewards such as money, status, aesthetics, that have no intrinsic value themselves, but become rewarding through their association with other forms of reinforcement. • The value (or our overall preference) we assign to a specific stimulus or event can be affected by different factors. For example: • Payoff, i.e., what kind of reward do the options offer • Probability, i.e., how likely are you to attain the reward • Effort or cost: how much it will cost or how much effort you need to make to obtain the reward? • Temporal discounting: the longer we need to wait to get the reward, the more effort is needed or the more discount the reward will have. • Context: this factors involves external things, like the time of day, or internal things, such as whether you are hungry or tired, etc. • Different tasks can be used to probe decision making processes in animals and humans • For example, we can train participants to learn and choose different objects associated with (1) different amount of reward or (2) different delay of the delivery of the reward. • For humans, the Iowa gambling task has been used to assess brain lesion patients' decision-making function. • Specifically, participants will be asked to choose cards from the 4 decks. Each card is associated with either winning or losing a certain amount of money. The A and B decks provide frequent small wins and occasional large losses; the C and D decks provide frequent small losses and occasional large wins. Most people will start by preferring A and B but gradually figure out it is better to choose C and D.

Place cell in rodents' hippocampus

• In 1970s, John O'keefe and colleagues found neurons in the rodents' hippocampus fired action potential whenever the animals traveled to a specific location in their environment. These neurons are called place cell which may encode the "where" information as a context memory. • Later, head direction cells (neurons encode the direction of the animal while they are navigating) and grid cells (neurons that fire at regular intervals as they navigate in an open area) were found in other medial temporal lobe regions, such as the entorhinal cortex (by Edvard Moser, May-Britt Moser, and others. • John O'keefe, Edvard Moser, and May-Britt Moser won 2014 Nobel prize in Physiology or Medicine, because their work in this area. • It has been claimed similar place cells may exist in humans and monkeys. • A huge body of evidence suggests that these medial temporal lobe regions may help us and other animals to build a "cognitive map" of the environment, associating object, locations, people, etc. together, resulting in episodic memory. • Temporal involvement of the hippocampus in memory: • Studies have found after rats learned a spatial location that was associated with a negative stimulus (e.g., foot shock), they would forget the information if their hippocampus was lesioned in a short time window after the learning (they will revisit the location associated with foot shock and show no freezing behavior). However, if the hippocampus was lesion a long time after the learning, the animals can still retain their memory. • This result may indicate that it may take some time for memory to "consolidate" into stable memory traces and the hippocampus is needed for this consolidation period. After the consolidation, memory traces may be supported by other brain regions and the hippocampus may not be important anymore (so that it can help with new memory). • Interestingly, if the animal's already-consolidated fear memory is reactivated (e.g., by bring it back to the location associated with food shock), then receives a lesion in the hippocampus, the fear memory can be destroyed again, indicating reactivated memory needs to be re-consolidated, which requires the hippocampus again. • However, some evidence showed that consolidated hippocampus-independent memory may be different in quality from the unconsolidated hippocampus-dependent memory.

Retrieval in the Hippocampus

• In another neuroimaging study (Eldridge et al., 2000), during the retrieval, participants were not only asked whether they can recognize the words they had learned, but also indicate whether they actually recollected them (episodic memory with a spatial and temporal context) or it merely seemed familiar to them. • They found that the hippocampus was selectively active only for words that were correctly recollected. The hippocampus was not activated by words that the participants had previously seen but could not recollect, indicating that the words merely seemed familiar . • Other studies have found other MTL regions such as the perirhinal cortex may be activated by retrieving 'familiar' items.

Executive functions: Error detection and monitoring

• In order to conduct goal-directed behavior to achieve our goals, we also need to monitor our behavior, or detect errors in order to correct them next time. This requires error detection or monitoring processes. • Many tasks can be used to study this process. For example, during Go/Nogo task, participants can easily make mistakes: they may make a response to the Nogo trials for which they are supposed to withhold their response, or they may withhold a response to a Go trial. • We can then analyze brain activity corresponding to the moment participants just made a mistake. • Stroop task, and many other tasks, can be also used to examine the neural mechanisms of error detection, response monitoring, or post-error adjustment.

Amygdala lesion in animals: Kluver-Bucy syndrome

• In the early 20th century, Kluver and Bucy (1939) documented unusual emotional responses in monkeys following damages to the amygdala. The symptoms, including a lack of fear, were later called Kluver-Bucy syndrome. • Kluver-Bucy syndrome is now defined as "a neuropsychiatric disorder due to lesions affecting bilateral temporal lobes, especially the hippocampus and amygdala. The major symptoms include (https://www.ncbi.nlm.nih.gov/books/NBK544221/): • Hyperorality - Socially inappropriate lickings and a strong compulsion to place objects inside the mouth (amygdala and the hypothalamus are important for feeding behavior) • Hypersexuality - Lack of social restraint in terms of sexuality, with inappropriate sexual activity and attempted copulation with inanimate objects • Eating disorder - Objects are placed in the mouth and explored with the tongue to counteract visual agnosia. Bulimia, which is an eating disorder characterized by binge eating, followed by purging, is also markedly seen and may cause weight gain. • Placidity - Flat affect and reduced response to emotional stimuli • Visual agnosia (Psychic blindness) - Inability to recognize familiar objects or faces presented visually"

incidental effect

• Incidental affect: The emotion that you are currently feeling can influence your decision because it may serve as important information, or act as "common currency" used to compare different options or affect attention and motivations (Peters et al., 2006). • Appraisal tendency framework: this framework assume that specific affective stats give rise to specific cognitive and motivational properties and thus yield certain action tendencies. Arousal and valence of the emotion can make differences. • Lerner and colleagues provided support for this framework using a endowment effect paradigm (the tendency to sell something at a higher price but buy it at a lower price - we all do that ;). -they manipulated emotion in order to modify customer motivation (more likely to buy at buying price if sad and more likely to buy at selling price if neutral, if disgusted they are more likely to buy at buying price but only by a small diff) Incidental affect: • Emotions may also affect whether we will make a thoughtful decision (based on reasoning) supported by the prefrontal cortex or a habitual response supported by the striatum (basal ganglia). • STUDY For example using a devaluation task, rats were first trained to press a lever to receive a food reward. Then they were fed to satiety, thus devaluating the reward. Rats that had not been previously stressed reduced their response rate, reflecting the devalued reward outcome; but stressed rats failed to modify their behavior following devaluation: they kept eating, continuing the habitual responding. • FINDING: So acute stress can shift our decision making from goal-directed (analytical) to habitual choices.

Executive functions: Inhibitory control

• Inhibitory control: the process that is used to inhibit or stop habitual responses, or prepotent responses so that a more wellplanned goal directed response can be possible. • Go/Nogo tasks are often used to test inhibitory control processing • We can manipulate the frequency of go vs. nogo trials to control the difficulty level of the task (more go trials will build stronger tendency of "habitual" action, which makes the inhibition more difficult. • Stroop task can also be used.

integral emotion

• Integral emotion: Emotions play an important role in making risky decisions (e.g., related to the possibility of monetary loss). People are loss averse - we weigh losses more heavily than gains. • Studies found that higher levels of skin conductance in response to losses relative to gains were associated with greater loss aversion, which is also associated with greater response in the amygdala. • Patients with amygdala lesions showed reduced loss aversion. Similar results were found in healthy participants administered a beta-adrenergic blocker (which reduces emotional responses). • Therefore, the amygdala may play a critical role in mediating aversion to losses, a finding that is consistent with the amygdala's role in threat detection. • How emotions affect decision making is a multidisciplinary fascinating research topic, related to behavioral economics, marketing, game theory, etc. There is a new field called neuromarketing or neuroeconomics in which scientists try to investigate the neural mechanisms related to decision making behaviors. The emotion system, including the amygdala and prefrontal cortex, play a key role.

Lateral prefrontal cortex: more related to action?

• Lateral prefrontal cortex is just anterior to the premotor or motor cortex. • These regions should be more related to planning, controlling actions, attention, etc. • The more anterior a region is, the further it is separated from the motor regions. Then, it may process more abstract cognitive/action representations.

Functional divisions of the prefrontal cortex

• Lateral: dorsal lateral prefrontal cortex (dlPFC) and ventral lateral prefrontal cortex (vlPFC) • Medial: dorsal medial and ventral medial prefrontal cortex (dmPFC and vmPFC). • Medial: anterior cingulate cortex (ACC) • Ventral/orbital: orbital frontal cortex (OFC)

What happens when there are selective lesions around the hippocampus?

• Memory deficits will become worse if the surrounding regions are also lesioned. • The medial temporal lobe regions may work as a network to support memory processing, although different regions may have their functions.

The two pathways in amygdala emotional stimuli processing

• One directly goes from the thalamus to the amygdala without being filtered by cognition or conscious control (called low road), because the cortex is bypassed, reach the amygdala rapidly (15 ms in rats). • The low road allows the amygdala to quickly receive a crude signal from the thalamus whether the stimulus is roughly like the CS, in which case it can immediately respond. • At the same time, sensory information about the stimulus is being projected to the amygdala via a cortical pathway (called high road). The high road is significantly slower, taking 300 ms in rats, but the cognitive analysis of the stimulus is more thorough.

Categorizing emotions

• One important question in emotion research is whether emotions are hardwired with dedicated brain mechanisms (position A) or states of mind that are assembled from more basic general causes (position B). • This debate has a long history, e.g., Darwin took the position A and William James (remember he is the father of north American psychology) took position B. • Contemporary: Influential affective neuroscientist Panksepp took position A (nativism), and Lisa Barrett and colleagues took position B (social or neural constructionism) • It seems researchers who study animals are more likely to take position A and who study human or human development are more likely to take position B. • Is there a middle road? (yes) • Basic versus dimensional categorization of emotions • Basic emotions and complex emotions • Dimensional theories of emotions

Categorizing emotions: Basic emotions and facial expression

• One of the most influential scientists who studied human facial expressions is Paul Ekman. • Ekman studied facial expressions related to emotions in different cultures and found that facial expressions human uses to convey emotion do not vary much from culture to culture. It is "universe"! • Ekman's research adds significant support to the basic (innate) emotion theory: Anger, fear, sadness, disgust, happiness and surprise are the six basic emotions, each with a specific facial expression.

Prefrontal cortex and cognitive control

• Our early understanding of the functions of the prefrontal cortex and how it is related to cognitive control came from brain lesion patients. • Phineas Gage is one of the most famous early cases, which we have talked about in the Emotion chapter. After his injury in the prefrontal cortex, "Gage is no longer Gage". His personality changed, his social behavior changed, ... • Because cognitive control, supported by the prefrontal cortex, is very important for goal - directed behavior, lesions in this brain area can disrupt different aspects of normal cognition, emotion, and behavior and produce an array of problems in real -world situation. • For example, focal injuries to the prefrontal cortex produce the following changes: o Deficits in planning complex behaviors. o Perseveration in responding, i.e., tendency to produce a particular response on successive trials, even when the context has changed, and the original response is no longer appropriate. They may have inhibitory control deficits or/and cannot flexibly adjust their behavior according to the changing situation. o Utilization behavior: an extreme dependency on prototypical use of an object without regard for its use in a specific context. Patients' behavior, instead of goal-driven, becomes stimulus driven. o They may become impulsive, distractible, or apathetic, or disregard social conventions. o Disruption of working memory

Dissociation between short-term and long-term memory

• Patient K.F., reported by Warrington & Shallice (1964), showed reduced digit span ability (only had about 2 items, instead of 5 to 9 items for healthy persons), due to damage to the left perisylvian cortex. However, K.F. retained the ability to form certain types of new long-term memory, e.g., associative memory (memory for association between two items). • Patient E.E., who had a tumor centered in the left angular gyrus, also showed below-normal short-term memory ability but preserved long-term memory (Markowitsch, et al. 1999). • E.E. showed normal speech production, but had poor short-term memory for abstract verbal material. E.E. also had normal visuospatial short-term memory and normal verbal and visuospatial long-term memory. • H.M. had the opposite pattern of deficits - impaired long-term but reserved shortterm memory. • These patient data support the dissociation between short-term and long-term memory, and between memory for visuospatial vs. verbal information

Patient R.B.

• Patient R.B.'s lesion was more restricted to the hippocampus, specifically the cells in the subfield CA1. • R.B. also had severe anterograde amnesia. R.B.'s retrograde amnesia is temporally limited and does not affect long -term events that happened more than a few years before the brain lesion. • R.B.'s amnesia is less severe than H.M.'s. • Together with other cases, such as patients who had transient global amnesia (which is temporary memory deficits due to a particular vascular events happened to the hippocampus), these data led some scientists to think that the hippocampus may be important for forming memory but may not for storing memory. • But recent evidence seems to show that some types of memory (detailed episodic memory) may always need the hippocampus. Semanticized episodic memory will be stored elsewhere (called multiple trace theory)

Implicit memory

• Procedural memory • E.g., how to ride a bike • A widely used task is sequence learning: • H.M. can perform well on this type of task, although he may not have conscious recollection about the experience. • Then which brain regions support this type of procedural memory? Motor system must play a role. (basal ganglia and motor system) • Classical conditioning • Also called Pavlovian conditioning. This is a type of associative learning in which a conditioned (neutral to the organism) is paired with an unconditioned stimulus (one that can elicit an established response from the organism) and becomes associated with it and starts to elicit "conditioned" response. • Sensitization and habituation • Sensitization: a response increases with repeated presentation of the stimuli. • Habituation: response to an unchanging stimulus decreases over time (related to repetition suppression we have talked about.

The ACC and MCC (midcingulate cortex)

• Recent literature calls for differentiation of the ACC from MCC • The ACC and MCC have different connectivity, respond to different tasks, and likely have different functions. -acc is more responsive to emotion affect -mid acc is more focused on hot cognition -ventral medial acc is more related to hot cognition -dorsal lateral is related to cold processing

Dissociation of declarative and nondeclarative memory

• Research has found that participants with amnesia were found to be faster at naming previous seen pictures than new ones (implicit memory), similar to healthy controls. But their recognition of the previous seen pictures was much worse than healthy controls. • Patient M.S. had a right occipital lobe lesion (BA 17,18, and 19). The patient took an explicit and implicit memory task. After being presented a list of words, in the implicit task, M.S. had to identify many words that were presented very briefly (with a range of durations). Among these words some were previously seen, some were not. If less time was required to identify the word after it had been seen previously, then there would be evidence for implicit memory. • In the explicit memory task (2 weeks later), M.S. had to identify which word he had seen. Healthy controls and amnesic patients also took the two memory tasks. -ms performed the same of both old and new memory tasks, amnesia patients did not perform well on old ones but performed better than the control group on both old and new. control group performed lower on old than on new. -of all participants, MS had the highest recognition/percent correct and amnesia patients performed the worst.

Different Forms of Memory

• Sensory Memory refers to the short-lived retention of sensory information, measurable in milliseconds to seconds. • Iconic (visual): when you are presented a visual stimulus for a very short time (50 ms), you can see the stimuli, when the stimulus is gone, your memory of that stimulus will also disappear quickly (in a couple of hundred milliseconds). • Echoic (auditory): when we recover what was said to us a moment earlier when we were not paying close attention to the speaker • Short-Term Memory refers to the retention of information over seconds or minutes • Short duration (approx. 30 seconds) • Limited capacity (7 +/- 2): e.g., someone just told you a new name or phone number • Subjected to Interference (prospective and retrospective interference) • Long-Term Memory refers to the retention of information over the long term, from hours to days, years. Some are even life long. • Declarative memory, which consists of our conscious memory for both facts we have learned (semantic memory) and events we have experienced (episodic memory). • Nondeclarative memory, which is nonconscious memory that cannot be verbally reported, often expressed through the performing of procedures (procedural memory).

Other brain regions and other emotions: disgust

• Since the insula is the primary brain region that process gustatory information, it plays a role in disgust. Patients with insular lesions have difficult in detecting disgust conveyed in various modalities. • Neuroimaging studies have found the insula is activated when participant process disgust emotion or being aware of bodily states such as gastric distention, body movement, or orgasm. • But patient study also found that patients with bilateral lesion in insula can still have affective feelings. Therefore, this brain region may be important for utilizing feeling experiences in complex cognitive processes, but was not involved in the generation of these feelings.

Other brain regions and other emotions: pain and empathy

• Singer et al (2004) found that the insula and anterior cingulate are activated when one is experiencing physical pain in oneself, as well as during the perception of physical pain in others. • Participants who scored high on a questionnaire that measure their degree of empathy showed greatest activation in these brain regions when they were perceiving pain in their romantic partners. -emotion and empathy are closely related

Basic emotions:

• Some researchers suggest shame and pride may also be basic emotions. • Pride and shame in athletes who win or loss competitions • In emotion research, there is one specific area in which researchers study how to use facial expressions to define the emotional state of the participants.

Amygdala: Structures

• The amygdala is a small, almond-shaped structure in the medial temporal lobe adjacent to the anterior portion of the hippocampus. It is a collection of at least 13 nuclei that can be grouped into three main amygdaloid complexes. • The largest area is the basolateral nuclear complex, consisting of the lateral, basal, and accessory basal nuclei. • The lateral nucleus (La) receives sensory inputs and sends information to the basal nucleus (B), and from there to the ventral striatum, to control actions in the face of threat. -The centromedial complex (ce), which consists of the medial nucleus and the central nucleus, receives information from the basal nuclei. It is connected to brainstem regions controlling innate emotional (or defensive) behaviors and associated physiological responses. • The smallest complex is the cortical nucleus (Co), primarily receives information from the olfactory bulb and olfactory cortex. It sends information to the medial nucleus and the hippocampus/parahippocampus (modulating memory formation).

Amygdala lesions: Human case S.M.

• The amygdala neurons contain receptors for different types of neurotransmitters hormones, or neuropeptides, including glutamate, dopamine, norepinephrine, serotonin, acetylcholine, glucocorticoids, estrogen, opioids, oxytocin, vasopressin, neuropeptide Y, etc. • If lesions are restricted to amygdala, human patients mainly show deficits in fear processing. One famous patient with bilateral amygdala lesion is S. M. • Studies with S. M. found that • S.M. fails to experience the emotion of fear and identify facial expressions of fear. • S.M. appears to have no deficit in any emotion other than fear. • S.M.'s inability to feel fear seems to have contributed to her inability to avoid dangerous situations.

The ACC: An important region in cognitive control

• The anterior cingulate cortex, i.e., the anterior portion of the cingulate cortex, is part of the medial prefrontal cortex. But it has different cytoarchitectonic structures and belongs to the limbic system. Therefore, very often this region is discussed separately from other PFC regions. • The ACC has been proposed to a crucial component of a monitoring system. Neuroimaging studies found that this region showed stronger activity when the monitoring demand is high in different tasks. It also plays a role in error detection, conflict monitoring, attention control, resolving response conflict, etc. • Anatomically, this region has many subregions that connect with different other brain regions, which makes the ACC in a key position to influence decision making, goal directed behavior, and motor control.

Other brain regions and other emotions

• The insular cortex is tucked between the frontal, parietal, and temporal lobes in the Sylvian fissure. • It has extensive reciprocal connections with areas associated with emotion, such as the amygdala, medial prefrontal cortex, and anterior cingulate gyrus. • It also has reciprocal connections with frontal, parietal, and temporal cortical areas involved with attention, memory, and cognition. • Insula is also the region that process taste (gustatory cortex), olfactory, pain, and temperature information. • The insular cortex also receive viscerosensory information, e.g., the gastrointestinal sensations or cardiovascular and respiratory afferents. • Because the insular cortex integrates all the visceral and somatic input, it can form representation of the state of the body and plays a key role in interoception, i.e., the perception of internal bodily states. • Studies have found the anterior insula and anterior cingulate are jointly active in participants experiencing emotional feelings, including maternal and romantic love, anger, fear, sadness, happiness, disgust, and trust. The posterior insula is activated by feelings of sexual desire. • The insula has been proposed as the "body information center". • Evaluative processing (assessing risks, valence, arousal) can activate this region. Patients with insular lesions reported both reduced arousal and reduced valence rating for both pleasant and unpleasant picture stimuli. But patients with amygdala lesions only had decreased arousal rating for unpleasant stimuli. • So the amygdala plays more important role in processing negative stimuli. But the insula plays a more broad role in integrating affective and cognitive processes.

Working memory

• The original working memory model has 3 components: Executive control, phonological loop (for vermal/auditory information), and visuospatial sketch pad (for visuospatial information). • People with lesion in the supramarginal gyrus may have deficits in phonological working memory, such as digit span. • Research has shown the left network consisting of the lateral frontal and inferior parietal lobes is involved in this phonological working memory. • For visuospatial memory (e.g., spatial span task), the bilateral (but more so the right hemisphere) parietal -occipital regions play a more important role. • Early neuroimaging studies provided support. For example, using PET imaging, Smith et al (1996) showed that when participants were doing a spatial location working memory task, activation was found in the right hemisphere, including the inferior frontal, posterior parietal, and extrastriate cortex in the occipital lobe, and when they performed a verbal working memory task (letters), activation was found in the inferolateral frontal cortex in the left hemisphere.

Prefrontal Cortex

• The prefrontal cortex usually refers to the part of the frontal lobe that is anterior to the primary motor (or sometimes premotor) cortex.

Animal lesion studies: delayed nonmatch-to-sample task

• There are different methods to test memory in animals. The delayed nonmatch-to-sample task is widely used in monkey and rodent studies. • The amygdala and hippocampus are close to each other and both are located it the medial temporal lobe. Do they play the same role in memory processing? • Using this task and monkey lesion model, studies have found that lesions of the hippocampus and amygdala produced the most severe memory deficits only when the surrounding regions (entorhinal, perirhinal cortex) was also lesioned. • Otherwise, whether the amygdala was lesioned or not does not significantly affect this type of memory.

Dorsolateral prefrontal cortex and working memory

• There is a huge body of evidence showing the prefrontal cortex is important for working memory: o Animal lesion studies have found that monkeys with prefrontal cortex lesions have difficulties to perform the delayed response task, but not the cue-response associative memory task. o Single cell recording (in lateral PFC) also found that some neurons showed sustained activity during the delay period of the delayed response task. • Evidence showing the prefrontal cortex is important for working memory: o Single cell recording also found that some neurons seem to specifically maintain information related to objects ("what" information), some for location "where" information, and some for both, i.e., 'what-where'. o The results indicate that cells in the lateral PFC exhibit task-specific selectivity, i.e., supporting the exact information in working memory.

Cognitive control or executive functions

• This diagram illustrate factors that may affect our decision making: • In this example, the person is asked to choose between two options, each of which has an inferred value. The values are determined by a weighted combination of multiple sources of information, internal or external.

The OFC/vmPFC and the dopamine system

• Value, emotion, and motivation are closely related and involve the big limbic system, including some PFC regions (e.g., vmPFC, OFC, ACC) and the midbrain dopamine system. • The ventral tegmental area in the midbrain contains dopamine neurons which send input to the limbic system (mesolimbic pathway) and other regions in the neocortex (mesocortical pathway). The medial PFC, i.e., the OFC, vmPFC and ACC, receives stronger dopamine input compared to the lateral PFC, so does the ventral striatum (ventral part of the basal ganglia). • Original scientists thought of dopamine as the neural correlate of reward or pleasure (liking), but currently its activity has been conceptualized as the expectancy of reward (i.e., wanting) and plays an important role in decision making and reward-based (reinforced) learning. • Research has also shown that the activation of dopaminergic neurons reflects prediction errors, i.e., the difference between the reward received vs. expected. • When we are expecting some reward and have not received it yet, we have a positive prediction error, this will yield a positive dopamine activity (wanting). • When we are expecting some reward and get the expected reward, no prediction error, no dopamine activity (neutral). • When we are expecting some reward but did not get it, there is a negative prediction error, dopamine activity will be inhibited (aversive). • Single cell recording studies using Pavlovian conditioning method supported the prediction error theory. • When an animal receives positive US (food), the dopamine neural activity in the VTA become stronger (suddenly receiving reward- positive prediction error). • After CS is paired with US, the CS starts to trigger dopamine activity. This is because when CS appears, the animal will have a positive prediction error (expecting something good, without consuming it yet). Learning will occur - learning the associations. • When the animal receives what it expects, no dopamine activity (because no expectation error). No new learning will occur. • When the animal did not receive what it expected to receive, dopamine activity will be depressed. Extinction will occur. • Regarding the function of the dopamine system, Kent Berridge at the University of Michigan proposed another very influential theory: • The dopamine release is the result, not the cause of learning. • The dopamine neurons may code informational consequences of prediction and learning, and then do something with the information. • The dopamine system also plays a key role responding to salient stimulus or event. • The dopamine system only mediates the ""wanting" component of reward processing, not "liking" or "learning". Reducing dopamine will reduce "wanting", which has significant implications in the current thinking of addiction. • Research has revealed different groups of dopamine neurons in the midbrain that respond to either valence (value) or saliency. (when the probability of reward is high, valence dopamine neurons show high activity and for saliency, it dopamine neurons will respond only if the probability of reinforcement is high for with aversive airpuff and juice reward) • Where is the prediction information in the dopamine system (VTA in the midbrain) coming from? • The VTA (limbic midbrain) is closely related to the cortical limbic system, including the hypothalamus, amygdala, hippocampus, ACC, OFC, vmPFC! During emotion process, cognitive appraisal, or other bodily activity (sex, sleep, eating, fight-flight, etc.), all the value information can be sent to the VTA • Studies also found that the inhibitory GABA neurons in the midbrain control the activity of the VTA dopamine neurons. It is likely that the cortical limbic system (e.g., amygdala or hypothalamus) sends value related information to the GABA inhibitory neurons to control the dopamine release (see figure 12.17 in the textbook). • One region in the thalamus, the dorsal posterior part of the thalamus, called habenula, may be one of the regions that convey the value information to the midbrain dopamine system. • Research has found that when animals approach a reward, the neural activity in the habenula decreases, but the midbrain dopamine neurons show increased activity (and vice versa). • The ventral striatum also plays an important role in value processing or decision making. • For example, neuroimaging research has found that prediction error also predicts brain activity in the ventral striatum. • The ventral striatum is involved in motivations. Therefore, value/reward (and punishment), dopamine activity, and motivations are closely related. We need to take actions based on the value of the stimuli or events.

Executive functions: Mental flexibility

• Very often we need to use different rules to deal with different things. We need to be able to switch between different rules. • One task frequently used in human neuropsychological assessment is the Wisconsin Card Sorting task. • In this task, participants will learn how to sort (i.e., match) the cards according to a specific rule, e.g., based on color, using the feedback given by the examiner. During the task, the rule will be changed, discreetly from one criterion to another (e.g., from color to shape to number). Participants have to shift sets accordingly and sort the cording based on the new rule. • If participants have difficult time to switch to new rules, they will have higher perseverative errors.

The vlPFC and inhibitory control

• Very often, if not always, we need to inhibit unwanted thoughts and behaviors so that we can select the ones that are consistent with our goals. • Therefore, inhibitory control is one of the most important executive functions we need for our goal -directed behavior. • Knight & Grabowecky (1995) asked patients with different brain lesions to listen to tones (auditory stimuli) and measured their brain responses using ERP. FINDING: -They found that compared to healthy controls, patients with the prefrontal lobe lesions showed stronger response in the auditory cortex, suggesting the signal is less inhibited. • Knight & Grabowecky (1995) Importantly, when asked to only pay attention to the tones in one ear and ignore those in the other ear, they found that the attended and unattended signal did not trigger different brain response in the auditory cortex contralateral to the lesion side. • This suggests that the inhibitory effect supported by prefrontal cortex is affected by the brain lesion. -right prefrontal cortex important for inhibitory control ANOTHER STUDY When the vlPFC activity is disturbed, inhibition control will also be affected. For example, Zanto et al (2011) asked participants to attend to either color or motion of a visual stimulus while stimulated participants' vlPFC, they found that not only participants' behavioral performance (i.e., accuracy on color recognition) became worse, the simultaneously recorded brain activity measured by ERP (P100 component) also showed reduced attention modulation, i.e., the advantage of attended stimuli over unattended stimuli was reduced. The p100 was larger for the ignored stimuli after rTMS. So, the inhibition on ignored stimuli was reduced because of the disturbance of the vlPFC by the rTMS. ANOTHER STUDY • Studies also found that disturbing the vlPFC primarily disrupted participants' ability to ignore irrelevant stimuli (i.e., disrupted inhibition) but had litter effect on their ability to attend to relevant stimuli. Therefore, the vlPFC is more important for inhibit task irrelevant information. • It has been found (Feredoes, et al 2011) that stimulating the dlPFC (dorsal) during the delay period of a working memory task led to an increased response in task-relevant brain areas when distractors were presented during the delay. For example, when we have to focus on face images and ignore house images, if our dlPFC activity is disturbed, we can process the faces better and our fusiform face area in the posterior part of the brain may show stronger activation. So, it is likely that the dlPFC is more important for maintaining task relevant information, consistent with its role in supporting working memory. TASK TO STUDY INHIBITORY CONTROL: • The vlPFC not only plays a role in inhibiting mental representations but also inhibiting actions! • In addition to the Go/nogo task, another task called stop signal task has also been widely used to examine inhibitory control function. • There are both go and stop trials in this task. For go trials, participants need to press a button as fast as possible after seeing a go signal. In stop trials, after the go signal is given, while participants are starting to make a button press, a stop signal will be given, and participants have to inhibit or abort the already prepared action. • Using stop signal task, Aron and Poldrack (2006) found that patients with lesion of the right inferior frontal were slow to abort a planned response. • A neuroimaging study has also found that successful or failed stop trials both produce a strong response in the right inferior frontal gyrus (vlPFC). In contrast, the vlPFC is silent on go trials. • The study also found that in the failed stop trial the primary motor cortex showed strong activity at the beginning of the trial, indicating a strong readiness for a movement, which cannot be inhibited by the signal from the vlPFC. • The subthalamic nucleus also plays a role inhibiting movement - indirect pathway is inhibitory! When patients with Parkinson's receive deep brain stimulation to improve their symptom, they start to have deficit in inhibitory control!

Executive functions: Problem-solving

• We can also test people's problem-solving capacity using different tasks (e.g., IQ task). • Another task mentioned frequently in the literature is the Tower of London task: • For example, participants will be given an initial state and asked to make movement of the balls in a specific number of step to produce the final state. We can manipulate the difficulty level (e.g., the number of steps) and record participants' errors. • We can also record participants' brain activity while they are doing the task.

What Controls Cognitive Control?

• We can use these variety of executive functioning tasks to test brain lesion patients or animals, or measure their brain activity when they are doing the task, to figure out which brain regions play an important role in supporting these processes. • A huge body of literature shows that it is the prefrontal cortex (PFC) that plays a key role in our executive functions.

• Where in the brain the memory information stored?

• Wheeler and colleagues investigated whether similar brain regions were activated during memory retrieval as those activated during perception. • They asked participants to learn a set of sounds (auditory stimuli) and pictures (visual stimuli), then do a perceptual and memory task in the MRI scanner. • In the perceptual task, stimuli were presented and brain activity was measured to identify brain regions involved in the perceptual processing of items. • In the memory task, the labels of the stimuli were presented and participants need to recall the stimuli (sounds or pictures) from their long-term memory. • Then the researchers compared the brain activities corresponding to perception of the stimuli and the memory of the stimuli. • A subset of brain regions activated during perception were also activated during memory retrieval. Therefore, retrieval of vivid visual and auditory information can be associated with a reactivation of some of the same sensory regions that were activated during perception of those stimuli.

Amygdala and explicit learning

• When participants were instructed that the blue square might be paired with electrical shock (not actually not), this learned explicit knowledge engaged the amygdala. Participants' skin conductance was positively associated with their amygdala activity. (this is instructed-fear learning paradigm) • That means the amygdala may facilitate this explicit learning of emotional responses (i.e., the expression of emotion): from verbal instructions to skin conductance changes. • Patients with amygdala lesion (e.g., S.P.) did not show the fear response.

Forms of Memory: working memory

• Working Memory, which refers to a limited-capacity store for retaining information over the short-term maintenance and for performing mental operations on the content of this store. • For example, we can remember (maintain) a list of numbers and we can add (manipulate) them in our mind using working memory. • persists for seconds to minutes. • Baddeley and Hitch (1974) proposed an influential 3-component working memory system: • Central executive mechanism that presides over and coordinates the interactions between two subordinate short-term memory stores (and longterm memory) • One short-term store is phonological loop, which deals with auditory information • The other is visuospatial "sketch pad", which deals with visuospatial information • Which is a dynamic form of short-term storage. Less like a storage place, more like a status; which are currently activated ideas or thoughts that are being worked on by a specific set of operations

N-back task

• Working memory: • n-back task is more often used for studying human working memory. • In this task, , responses are required only when a stimulus matches one shown n trials earlier. The contents of working memory must be manipulated constantly in this task because the target is updated on each trial. • We can manipulate the load and delay using different "n" value.

Executive functions: Working memory

• Working memory: As specified in Baddeley's working memory model, executive control is needed to maintain and manipulate the information in the working memory, i.e., working WITH memory. • Delayed response tasks, (shown a stimulus and then there is a delay and after the delay, u need to pick the stimulus u saw, nonmatch to sample is the opposite) • Delayed-match-to-sample or delayed -nonmatch -to -sample task, are often used to test working memory maintenance. • We can manipulate the length of the delay, the load of the task (how many wells), or add interference ... STUDY -monkey will be given two choices, int eh delayed match to sample the monkey has to choose the image they saw before, and in the nonmatch to sample they need to choose the one they didn't see before -can manipulate the numbers of pics and the time the monkey has to respond

study with monkeys on working memory

▪ In this delayed response task, a monkey is shown that food is associated with a specific location. ▪ Then there is a short delay during which the animal cannot see the food well, and researchers will cover the food well. ▪ Then the monkey needs to find the food well. ▪ In this task, the monkey need to hold the information of where the food is during the delay, until they are allowed to find it.

Functional organization of the prefrontal cortex (O'Reilly, 2010)

▪ Ventral-dorsal axis: ▪ Regions that are more ventral are more likely to paly a role in What related to executive processing. ▪ Regions that are more dorsal are more related to "how". ▪ Anterior -posterior ▪ Anterior regions are more related to more abstract representations. More posterior, more concrete motor plans. ▪ Lateral-medial ▪ More medial regions are related to processing of information that is more related to self, emotion, reward, internal stimuli, etc (hot). Lateral regions are more related to "cold" information (not related to self, emotion, etc.).