Neuropsych Chapter 18
Studies of hippocampal patients demonstrate four conclusions:
Anterograde deficits are more severe Episodic memories are more affected than semantic memories Autobiographic memory is especially affected Patients cannot time travel to the past or future
what is consciousness
Awareness and awareness of awareness Blindsight, blindtouch, implicit memory
grid cells
Discharge at regular spatial intervals that mark nodes Nodes represent points throughout the environment and form a grid Orient to different cues and can be influenced by direction
place cells
Discharge when an animal is in a certain place in an environment (both when walking there and if carried there) Maintain activity in the dark When the environment is rotated, cells discharge according to new pattern Marks the "Place" the animal is in Discovery won the Nobel Prize in 2014 (John O'Keefe, May, and Edvard Moser)
stm: dorsal and ventral streams
Dorsal stream short-term memory for locations, space connections from parietal to frontal vision for action Ventral stream short term memory for objects connections from temporal to frontal vision for perception
dorsal and ventral streams
Dorsal stream (where) Actions toward or away from objects Egocentric Ventral streeeam ((what) Complex actions that use objects for references Allocentric Both project to frontal cortex where info from thee what and where pathways is integrated and also from parietal to HC
___ and ___ regions activate when see self, versus when see pictures of others
Frontal and parietal regions activate when see self, versus when see pictures of others
are conscious and attention the same processes?
Fundamentally different 2 distinct processes top down (concept driven) attention bottom up (data driven) consciousness Consciousness gives us the "gist" of the world Attention zooms in on specifics of the world
explicit memory for events and facts is ___ and ___ and consists of ___ memories and fact-based ___ memories
conscious, intentional, personal experiences/episodes memories, fact based semantic
Amygdala
input from all sensory systems Multimodal (neuron) cells Sensitive to threatening or dangerous stimuli Has sophisticated cortex-like properties
Consolidation Theory (Larry Squire)
--Hippocampus consolidates memories to make them permanent and then sends them to be stored in the neocortex --Accounts for preservation of old memories when hippocampal damage occurs --As more damage occurs, the more old memories will be lost
1. Explicit Memories
--Semantic -- facts/knowledge (Obama is president) --Autobiographical - Memory of life experiences ---Autonoetic awareness "future memory, time travel" ---Conscious intentional remembering --"Top-down" processing
Type of Implicit memory: Priming
--Stimulus is used to sensitize the nervous system to a later presentation of the same stimulus --Occurs without conscious recollection --Word stem priming: Chart ....Ch__t --Line-object priming...
Reconsolidation Theory (Natalie Tronson and Jane Taylor)
-Reconsolidation (memories will rarely consist of a single trace or neural substrate) ---each time a memory is used, A memory reenters a labile phase when it is recalled and is then restored as a new memory -Results in many different traces for the same event
fugue state
Form of memory loss where individuals have no knowledge of their former life
consolidation theory: in hippocampal damage, ___amnesia may extend back for how long? what about for temporal damage
1 or 2 years, one-2 decades
Neuropsychological Theories of Emotion: Cognitive asymmetry/lateralization theory (Guido Gainotti)
1. (Guido Gainotti) a. right hemisphere is more engaged in automatic components of emotion (strong/negative such as fear and anger) i. generates feelings b. left hemisphere plays a role in the cognitive control of emotion i. interprets feelings (because language?)
3 distinct networks of attention (Posner and Peterson, 2012)
1. Alerting: midbrain RAS norepinephrine locus ceruleusPFC and PPC=rapid simultaneous detection 2. Orienting: 2 brain networks: dorsal attentional system and ventral attentional system=selects modality or a spatial location to attend to a. Dorsal attention system: town-down visuospatial b. Ventral attention system: bottom-up reorienting 3. Executive control: dual networks: frontal-parietal system and thee cingulo-opercular system; a. Frontal-parietal executive control system=transient attention (like attending to task instructions) b. Cingulate-insular operecular system=sustained attention (like during task performance) c. Key: frontoparietal control system: moment-to-moment task; cingulo-opercular system: task set maintenance
emotions affect decisions
1. fMRI study gambling task, lose money experience regret=activated OFC and anterior cingulate at first 2. after learning and lost less often, OFC activated before the choice was made 3. suggests OFC linked to both feeling regret and anticipating and avoiding feeling regret 4. OFC lesion patients reported no feelings of regret when lost
why does childhoos amnesia happen
1. hippocampal neurons form new connections, they form new memories but disrupt neural circuits that support memories already acquired. 2. more permanent memories are formed when the acquisition of new neurons by the hippocampus slows
hera predicts
1. left pfc differentially more engaged in encoding semantic information than in retrieving it 2. left pfc differentially more engaged in eencoding episodic information than in retrieving it 3. right pfc differentially more engaged in episodic memory retrieval than is the left pfc
asymmetry in emotional processing
1. production of affect Left hemisphere lesions lead to a flattened mood Aprosodia appears after right hemisphere lesions (no tone to speech) Anterior lesions reduce facial expressions Left frontal lesions decrease spontaneous talking Look at graphs- frontal lobe lesions significantly reduce the number of facial expressions, spontaneous talking is significantly reduced for left frontal lesions and increased for right frontal lesions
Brain Circuits for Emotion: limbic system
Amygdala and prefrontal cortex especially important for emotion
Body space: Grasping space: Distal space: Time space:
Body space: anything that comes in contact with surface of body Grasping space: anything you can touch without having to move your body Distal space: anything distal to you, must move to get to that thing Time space: I was/will be in that space; can't separate time from space
Neural Substrates of Implicit Memory: cerebellum
Cerebellum ---Plays a role in classical conditioning ---Lesions to the cerebellum abolish conditioned responding to a puff of air to the eye
Neural substrates of spatial behavior Hippocampus:
Cognitive mapping Disrupts piloting (navigating around obstacles) or dead reckoning (path integration or estimation of how fast/far traveled by biological movement; optic flow) Has specifically related cells discovered by single-cell recordings: Place cells Head-direction cells Grid cells (entorhinal)
conscious processing
Controlled, effortful, attentive, conscious Requires consciousness and focused attention Top-down (search for street name)
Damage to the ___ disrupts emotional memory, but not ___ or ___
Damage to the amygdala disrupts emotional memory, but not implicit or explicit
Different kinds of learning and memory use ____ neural processes
Different kinds of learning and memory use independent neural processes
emotional memory
Emotional Memory ---Memory for affective properties of stimuli ---Fear conditioning ---Noxious stimulus is associated with a neutral stimulus to elicit emotional response ---Bottom-up" and "Top-down" processing
Left Prefrontal Cortex in memory
Encodes semantic and episodic information
Hippocampal damage =___ memory- ___ ___ ___ is impaired
Hippocampal damage = contextual memory - related to self is impaired
Four principle behavioral components of emotion:
Physiology (CNS and PNS activity) Distinctive motor behavior (e.g., facial expression) Self-reported cognition (subjective and objective) Unconscious behavior (like intuition)
anterograde amnesia
Inability to acquire new memories
retrograde amnesia
Inability to remember old memories
Inattention
Inattentional blindness Failure to notice something during the performance of another task Simons and Chabris (1999) Change blindness Failure to detect changes in the presence, identity, or location of objects in scenes Attentional blink Failure to detect a second stimulus if it is presented within 500 ms of the first
Herpes Encephalitis
inflammation affects temporal lobes and leads to amnesia insula may bee implicated in retrograde amnesia
consciousness
Level of responsiveness of mind to impressions made by senses Complex thought processes to subjective experience of awareness of "inner self" Collection of processes happening simultaneously: arousal, perception, attention, and working memory Varies across the lifespan and varies across the day
Divided attention (bottleneck Kahneman 1973)
Limited capacity that must be allocated to different activities Performance on tasks suffers when we divide attention between too many tasks Driving and talking on your cell phone MultitaskingPFC
childhood amnesia
Loss of memory for the early years of life. episodic memory has not matured. as new
Cognitive Control of Emotion
Luckily we can control our emotional responses (usually) ---controlled by cingulate cortex and prefrontal cortex ---Can immerse yourself fully in a sad movie, or keep yourself from getting too emotionally involved
Short-term or working memory
Memory for recent events and their order Mediated by the dorsal and ventral pathways to two regions of the frontal cortex
Super Memory
Most of us get the gist, but do not retain all details Rare individuals have almost perfect memory for details: Autobiographic - can tell where and what was doing at any time on any day asked about Semantic - retains memory for most facts and knowledge exposed to when memorizes Case Study "S" memorized this table in 2-3 minutes Perfect recall 16 years later! The Mind of a Mnemonist by Luria (1968)
Neural Substrates of Implicit Memory
Neural substrates of implicit memory Neocortex Basal ganglia Huntington's chorea Loss of cells in the basal ganglia Leads to deficits on tests of implicit memory Motor cortex Activated during learning of the Pursuit-Rotor Task Acquisition of implicit knowledge requires a reorganization of the motor cortex
regulator of consciousness?
One study found that when stimulating thee claustrum of a patient with epilepsy, she lost consciousness but when stopped stimulating she awoke Intruiguing because not much is known about what thee claustrum does, so perhaps it regulates the perceptual world and if we perceive it or not..
Attending to either auditory or visual input selectively activates either auditory or visual cortex (increased sensory processing) but does not activate
PFC but, dividing attention to focus simultaneously on both, activates thee DLPFC. (study)
Social Neural Networks
Patients with lesions who displayed impaired social behavior Averaged brain regions together Connected common regions to make 4 networks: -----amygdala network; mentalizing network; empathy network; mirror network
Trieesman et al 1988 Visual processing task
Pop-out effect: people use automatic feature search conscious conjunction search: requires spatial search
Role of OFC
Represents positive and negative reward values of stimuli Learns which stimuli are reinforcing or pleasurable and which are to be avoided (and when they switch) fMRI studies show that pleasure activates the OFC, esp. mid-anterior OFC e.g. rate pleasurableness of chocolate, when hungry and not hungry; OFC also codes for pleasure of music, drugs, orgasm
Right Prefrontal Cortex in memory
Retrieves episodic information
asymmetry in emotional processing: interpretation of affect
Right hemisphere lesions produce deficits in comprehensions and judgment of emotion Right frontal lobe and temporal lobe lesions produce impairments on facial expression tests Right frontal lobe lesions produce impairments in understanding and using humor
what is attention
Selective awareness of a part of the environment "mental spotlight"
Six Basic Emotions according to Paul Eckman
Six Basic Emotions: fear, disgust, anger, happiness, surprise, sad
Implicit Memories
Skills, conditioned reactions Riding bike, using language Unconscious, non-intentional "Bottom-up" processing dorsal stream pathway
spatial behavior: key concepts Spatial behavior: Topographic memory: Cognitive maps:
Spatial behavior: guides us through space, thoughts about space Topographic memory: ability to move through space from one place to the next; remembering the relation between points Cognitive maps: mental representations we have of physical space around us
neuropsych assessments for spatial behavior
Spatial memory test: to diagnose right hippocampal damage severe enough to affect memory Spatial visualization test: fold a paper, and punch a hole through the 2 sheets, when the paper is unfolded where will the holes be Boundary expansion: if you give someone with hippocampal based amnesia the sample drawing on the far left and have them copy it, patient will always draw object, in faithful representation in its size to frame, control subjects will put its own scaling and draw it smaller Spatial orientation test
Selective attention
Spitzer and Desimone and colleagues 1988 Examined monkey VC neurons' responsiveness to lines of different orientation Information processing in the visual system differed depending on the amount of effort Cell recording in monkeys and fMRI in humans suggest that the 2 types of attention rely on different neural processes
Transient Global Amnesia
Sudden onset and short course Loss of old memories and inability to form new memories
Neural Substrates of Explicit Memory
Temporal-frontal lobe neural basis for explicit memory
emotion
The cognitive interpretation of subjective feelings
Multiple-trace Theory (Lynn Nadel & Morris Moscovitch)
Three kinds of (learning event) memory ---Autobiographic memory (HC) ---Factual semantic memory (other temporal) ---General semantic memory (other areas ie language areas) -Each type is dependent on a different brain area -Old memories are more resistant to amnesia because they change location in the brain as they are recalled memories change throughout a person's life as they are recalled/reevaluation/restored
TBI commonly produces ____, and amnesia damage depends on
Time dependent retrograde amnesia, severity of injury
social cognition and the brain
Understanding other's actions Biological motion (waving hello) Cells of the STS Mirror neurons (smile back at someone) Premotor cortex Can be majorly impaired with brain damage Test: leave 1/3 person's face blank and interpret what blank expression should be
social cognitive neuroscience
Understanding other's mind Theory of mind: 1. ability to attribute mental states to self and others 2. Ability to understand behaviors on the basis of mental states Neural regions active during social judgment 1. Orbito-frontal cortex 2. Amygdala 3. STS cortex
the self
We are self-aware. But how? ----- Right fronto-parietal network (includes mirror neurons regions in each) -----Cortical midline networks (similar to default mode network); Theory of Mind? 0 Humans and apes recognize themselves in mirror
neural substrates of consciousness
We don't know Frontal and parietal regions are compromised when in unconscious states Look at pictures in book I think
Affect
inferred behavioral state of an individual (e.g., happy) -----Conscious subjective feeling about a stimulus affective behavior is internal and subjective
neurological theories of emotion:Cognitive-emotion interactions (Joseph LeDoux)
a. emotions evolved to enhance our survival b. inter-relatedness of cognitive and emotional processes c. mainly applies to fear d. fear system is both unconscious (jump when startled) and conscious (we know that we now feel scared) e. e.g. classical conditioning: amygdala damage disrupts fear conditioning
Three Major Neuropsychological Theories of Emotion: Somatic Marker Hypothesis (Antonio Damasio, 1996)
a. when confronted with a stimulus of biological importance, the brain and body change b. reductions in body reactions lead to reduced intensity of emotion c. emotion is fundamental to survival d. emotion Is necessary for rationale decisions e. an "appraisal theory" of emotion i. bodily reactions increase, so we feel emotion ii. reduce bodily reactions=reduce emotionality? Potential therapy tool
medial teemporal structures in memory: on right side is
amygdala and hippocampus
Kluver-Busy syndrome
anterior and lateral temporal lobe damage that includes amygdala: loss of fear, hypersexual oral fixation, eat any food, visual agnosia
h.m. had what type of amnesia and could not do what?
anterograde, acquire new memories and some retrograde. retained semantic memory before and some after surgery
HERA = Hemispheric Encoding and Retrieval Asymmetry
areas activated during acquisition or recall of verbal information. in left ventrolateral PFC, right premotor cortex, prefrontal areas, parietotemporal cortex
Previously Papez Circuit
believede that structure of limbic lobe forms anatomical basis of emotion limbic structures act on hypothalamus to produce emotion now limbic circuit expanded to include large focus on amygdala and prefrontal cortex includes, hippocampus, hypothalamus, amygdala, olfactory bulb, septum, cingulate cortex, and fornix
Physiology (CNS and PNS activity)
changes in neurohormonal and somatic activity elevates blood pressure, heart rate, perspiration, etc.
Unconscious behavior (like intuition)
cognitive process of which we are not aware that influences behavior intuition
other aspects require focused attention
conjunction search serial processes; scanning for particular combination of features feature binding: how attention glues together different features to form a unitary object (eyes + nose + mouth=face) task: look for sad and happy face
Damage to HC also can damage its...
connections Perforant pathway (from HC to posterior neocortex) Fimbria-fornix pathway (from HC to thalamus and PFC, Basal Ganglia, hypothalamus)
unconscious interference
processes outside awareness and learned by experience
what is the study related to gist
controls sacrifice accuracy that gist formation occurs. participants given a list of words. a lure word (word related to words on study list but not on the list) and controls claim they studied the lure words. amnesic patients with hippocampal damage had reduced false recognition and have a weak gist
Dorsal stream (parietal) problems
deficits in visuospatial exploration displaced visual attention, inability to perceive more than 1 stimulus, defective visual control of movement, inability to follow a moving target, defective accommodation and convergence, inability to maintain fixation, inability to direct gaze to targets voluntarily
Korsakoff's Syndrome
degeneration of thalamus and mammillary bodies stemming from malnutrition often from alcoholism; thiamine(B1) deficiency; profound amnesia, confabulation, apathy; B1 treatment can stop further damage but cannot repair previous damage 1)anterograde amnesia 2) retrograde 3) confabulation (make up stories and won't admit memory loss) 4) meager content in conversation 5) lack of insight 6) apathy kills cells in medial part of diencephalon (between brain) at top of brainstem including medial thalamus and mammilary bodies of hypothalamus
what is gist and its purpose according to Schacter and Addis. what is a shortcoming?
describes the objective of reconstructing a memory, and its purpose is allowing us to anticipate and respond to situations in the future in ways that benefit from our past experiences.
what is a shortcoming of gist
details are unimportant, so it makes it prone to errors of commission/omission
hippocampus is important for ___ memory
episodic
3 types of long term memory
explicit, implicit, emotional
Three types of long-term memories
explicit, implicit, emotional
sacral, lumbar, low thoracic, high thoracic, cervical
fear anger, fear, anger anger
Automatic vs. conscious processing certain aspects of visual processing are automatic
feature search scanning for specific features features may be biologically significant
Other Cortical Regions for Explicit Memory includes
frontal cortex
medial temporal structures in memory: hierarchy
frontal/parieetal/temporal/occipital/cingulate cortices-->perihinal cortex ¶hippocampal cortex-->entorhinal cortex-->hippocampus and back to regions
h.m. had what type of anterograde amnesia and what could he not do
globe anterograde amnesia: Impairment in the ability to form new memories across a variety of areas, spatial and topographic, events that took place learning of new words, people who made news after injury
Tulving's patient K.C.
had amnesia for personal experiences, could not recollect autobiographical events in which he was present, could not say what he would be doing later in the day, next day, or any time in life. retained semantic memory, remembered parents had cabin
emotional memories contain both __ and ___ aspects
implicit and explicit
Implicit and explicit memory are ____of each other
implicit and explicit memory are independent of each other
2 dimensional space of emotion
includes aroused/not aroused and pleasant/unpleasant unpleasant and aroused: fear & anger unpleasant and not aroused: disgust and sad pleasant and aroused: surprised and happiness pleasant and not aroused: sleepiness and calmness
superiour autobiographical memory
increased gray matter
Dorsal stream makes projections to temporal lobes
involved in spatial navigation and object perception, combines egocentric and allocentric info about objects in space hippocampus involved in spatial memory London taxi drivers train for 4 years to get license Have larger posterior HC volume, and scales with number of years spent driving a cab One example: different species of birds eat in different ways: food storing and non food-storing
what did Fredric Bartlett say about remembering
it is an active process of reconstruction
semantic memory
knowledge about the world (nonautobiographical) ability to recognize family, friends, & acquaintances, info learned in school, reading, writing, math, vobab, historical events
cerebellum mediates
learning discrete, adaptive, behavioral responses
autobiographic memory depends on
medial temporal lobe and ventral PFC and connections made by uncinate fasciculus
in what area of brain was h.m. impaired
medial temporal lobes--parahippocampal gyrus
mirror reading task
mirror drawing task: trace b/w outlines of the star while looking at mirror reflection, h.m. showed improvement even though he did not remember doing task previously
Alzheimer's Disease
neuron death that starts in temporal lobes and spreads around other cortex, anterograde then retrograde medial temporal cortex to first show damage-->shows related to anterograde
balint's syndrome
not able to take a cup, a bottle of something and pour into cup "softening" of the parietal tissue
retrograde amnesia may be ___
older memories may be more accessible and newer ones may not, incomplete
rhinal cortex
part of perirhinal cortex Cortex that surrounds the rhinal fissure Includes the entorhinal and perirhinal cortex Projects to the hippocampus
example of how perception affects memory
people are asked to draw a half-full upright glass. some may draw line horizonally (action representation) or tilted (iconic representation)
false memory in car accident example
people remember gist of accident but not good at remembering details. some may remember details but not others and memories can become distorted. observers can be primed by other observers to "remember" things that may or may not have happened.
medial teemporal structures in memory: on left of brain is the
perihinal cortex, parahippocampal cortex, entorhinal cortex
pursuit rotor task
person attemps to keep a stylus in a particular location on a rotating turnable about the size of a vinyl record album. task draws on skills similar to those needed in mirror drawing. performance associated with increased blood flow to motor cortex, BG, & cerebellum. also associated with motor cortices and nucleus of thalamus
episodic memory
person's recall of SINGLE events, in impairment they have trouble recalling specific experiences
Locations of spatial impairment egocentric disorientation heading disorientation landmark agnosia anterograde disorientation spatial mapping/memory deficit
posterior parietal-unable to represent location of objects with respect to self posterior cingulate-unable to represent direction of orientation with respect to environment lingual gyrus-unable to represent appearance of prominent landmarks parahippocampal gyrus-unable to learn new representations of environmental information hippocampus-anterograde and retrograde amnesia, especially for rich spatial details
Orbito-frontal lesions in monkeys:
reduced social interaction, loss of social dominance, inappropriate social interaction, altered social preference, reduced affect (flat), reduced vocalization Similar to Phineas Gage's OFC lesion
patient M.L.
retrograde amnesia for episodic experiences, damage to right PFC and white matteer, including uncinate fasciculus which connects to temporal lobe and ventral PRC
Perirhinal damage results in
selective to object recognition (ventral stream)
autonoetic awareness of time
self-knowledge which allows us to bind together awareness of ourself as a continuous entity, difficulty in traveling subjective through time in past or future. people with hippocampal and frontal cortical damage have trouble with this. difficulty in behavioral self-regulation and using past experiences in making future decisions
2 types of explicit memories
semantic and episodic
amygdala does what
send outputs to stimulate hormone release and activeate ANS
somatic marker continued
spinal injury actually reduces emotionality, and scales in effect as thee injury is higher up toward the brain physiology altered: less facial expression, motoric behavior, autonomic arousal, endocrine changes emotion is fundamental to survival in social environment
processing emotional stimulus
stimulus to sensory thalamus to cortex and amygdala
Gollin incomplete figures test
subjecets shown series of drawings in sequence from least to most clear, people have to see next panels to identify drawing. on reteention test later, people identified image in earlier panels
Self-reported cognition
subjective emotional feelings objective (plans, memories, ideas)
3 theories of amnesia
system consolidation theory, multiple trace theory, reconsolidation theory
semantic memory does not depend on what brain areas
temporal and frontal lobe regions adjacent to neural regions for episodic
in explicit memory, most are in what lobe
temporal, hippocampus, rhinal corties, pfc, nuclei in thalamus. regions that make up explicit memory circuit receive input from neocortex, and from ascending systems in thee brainstem including acetylcholine, serotonin, and noradrenaline activating systems
opographic disorientations: Egocentric disorientation: Heading disorientation: Landmark agnosia: Topographic amnesia: Retrograde spatial amnesia: Anterograde amnesia: Spatial distortion:
topographic disorientations: Egocentric disorientation: e.g. cannot point to objects in front of you with eyes closed Heading disorientation: unable to chart a course to head out to (no sense of direction) Landmark agnosia: inability to identify individual landmarks along a route Topographic amnesia: inability to remember the relationship between landmarks Retrograde spatial amnesia: for places before the injury Anterograde amnesia: for new places since injury Spatial distortion: feel too small or big (Alice in Wonderland) out of body experiences; lost space
automatic processing
unconscious Involuntary, without awareness Does not interfere with concurrent processes Can be innate property of sensory info or the result of training Bottom up (stop at red light)
head direction cells
• Discharge when the rat points its head in a particular direction • Similar to a compass needle; fire as long as the head is facing a direction • Influenced by surrounding cues • Continue to fire in the dark • Can change orientation depending on the cues of the environment