PSC 130: Final Practice Question Study Guide

Dementia

A progressive cognitive decline beyond what is expected with normal aging (e.g., Alzheimer's, Parkinson's, Huntington's, semantic dementia). Numbers in U.S. -15% over 65 exhibits some form of dementia - estimates range from 25-47% by 85

According to Jacoby (1983), when does generation hurt memory compared to reading?

On an implicit memory test

Give an example of a Memory Systems theories of LTM (Explicit vs Implicit)

Tulving model - serial in / parallel out mode episodic (explicit)--> semantic (implicit)--> perceptual/procedural --> - When you experience something, you process it with perceptual and procedural characteristics (how we see it), then semantically (what does it mean), and if we are lucky we go to episodic memory and glue everything together. When retrieving we can independently retrieve information from either of the modes (episodic, vs semantic vs perceptual/ procedural)

in a cued recall test will familiarity or recollection help you most?

familiarity will not help you as it needs to be presented to you- in free recall -->recollection --> extra specificity of time and place is needed all implicit memory has to do with the cortex, but conceptual implicit memory poses a challenge to this

What happens if you legion to parahippocampal cortex in the BIC model

have issues with places, knowing where they are, and contextual information. Where did you study this word. They would not know because contextual information is lost. They will still have familiarity as it is supported by the perirenal cortex

What is temporally graded retrograde amnesia? Describe a type of memory test that could be used to demonstrate that retrograde amnesia is temporally graded.

long-term memory is fine for remote evets, but poor long-term memory for more recent events. EXAMPLE ECT - e.g., Cohen & Squire- tested (public events) prior to treatment then 2 hours after 5 ECT treatments * severe Antegrade Amnesia * temporally graded RA (extending back several years). - If asked about things right before treatment, they are very good before ECT, but worse after ECT, so induced amnesia for recent memories. - remembered things that happened well before impairment, so remote memories were fine

what patterns of brain activation would you expect to see in aging adults during a verbal working memory task

more bilateral frontal lobe activation

Interference in the BIC model:

when encoding an event, things learned prior (proactive interference) will hurt and things learned after (retroactive) will affect memory, because it has been encoded in similar context - linking of objects to the context and this is what impacts memory. That is why changing context will decrease memory. - if given a similar lure, you will falsely think you saw it, when you didn't

How do you dissociate AD from Parkinson's/ Huntington's

someone with Alzheimer's will show impaired: STM, Recall, Recognition, familiarity, conceptual implicit, and semantic knowledge while someone with Parkinson's will only have the skill and semantic (action) impairment

What could be causing the brain changes seen in aging

volume reduction due to lower synaptic densities and demyelination, rather than cell death...

Retrograde vs antegrade Amnesia

- Anterograde amnesia - impaired memory for events that occur after the trauma--> cant learn new information - Retrograde Amnesia - impaired memory for events that occurred prior to trauma (can be graded or flat) --> graded retrograde amnesia: get less severe as you go back more in time

Alzheimer's (AD) Brain regions

- Atrophy and less brain activation in cortex throughout the temporal, frontal and parietal lobes - entorhinal --> hippocampus --> frontal --> parietal-> - ventricles are bigger on AD individuals - in a PET scan, there should be a lot of cortical activation, but in AD brain it is less active-

Declarative vs. Procedural

(Cohen & Squire, 1980) - Declarative (explicit) --> memory that can be declared, things we can talk about (knowledge and events), depend on MTL dependent, but slowly consolidated to cortex --> not only episodic but also semantic, things we can talk about and verbalize. --> within declarative memory, there is knowledge of the world (semantic) and events (episodic). - Procedural (implicit) --> learning that can't be verbalized or consciously expressed (non declarative), cortex dependent. Skill learning --> things like drawing in a mirror, something we can do, but isn't explainable, can't verbalize it, recognize abstract line drawing

Episodic vs. Semantic memory

(Tulving, 1972) Two forms of LTM Episodic Memory (explicit) - conscious memory for episodes or events, dependent on the MTL. Things that happened to me, I lived through it. Organized based on time and space (see your family home stairs, remember how you fell there) --> paralleled system that supports implicit memory- Semantic Memory (implicit) - general knowledge about the world, dependent on the cortex (e.g., lateral temporal lobe, visual cortex, but outside MTM, etc) --> learn a new fact, at some point we didn't know this, so the kid has a memory of this event, but his cortex is learning the general knowledge and he might be able to answer that even though he doesn't store memory for the episode. You acquire some knowledge and change what you know of the world and use episodic or semantic knowledge. --> starts as episodic memory (remember you learned it in class), but after time, it's consolidated and loses its spatial and contextual underpinning, and we just remember the facts Can account for: - Behavioral dissociations between implicit and explicit memory - example patient HM (could learn mirror drawing, even though he didn't have explicit memory of doing the task) - MTL lesions disrupt explicit memory - Imaging dissociations between implicit and explicit memory (when using episodic memory we use MTL)

is conceptual implicit memory preserved in amnesics?

(conceptual rather than perceptual retrieval cues)e.g., fact learning (Schacter, Harbluck & McLachlan, 1984) HOW: - give you conceptual cues, make up false facts and see if the facts will take hold. - Study: told "Bob Hope's father was a fireman" - Test: "What did Bob Hope's father do?"- week later brought in and asked about the implanted questions RESULTS: * amnesics can learn these new facts, even though they don't remember where they learned them - the amnesics can be tricked easily, don't know where the information came from, so they assume the fact is true, and are convinced the information is true, creating false knowledge IMPLICATIONS: --> conceptual implicit memory is at least partially preserved in amnesia- can learn new information, even without a hippocampus

The Binding of Items and Context (BIC) model of MTL function

(e.g., Dianna, et al; 2007; Eichenbaum et al., 2007; Fernandez et al., 2006; Davachi 2006) - three components and the pararineal is perceiving item information from the ventral stream, telling us of what objects are in the world, then fed into the Entorihinal cortex then fed into the hippocampus. - dorsal stream: taking care of 'where' information (spatial) and projects into parahippocampal cortex and from there into the Entorhinal cortex and then hippocampus. Main Thing: perirhinal cortex is processing 'What' or item/object information so identifying things you have seen before (familiarity) - HIPPOCAMPUS: Binding (linking things together) - selectively important for recollection/episodic memory (recent and remote) - stores representation that links them together - Complex scene perception- Precise WM - where the object was and what color, then object and context is needed and this is done in the hippocampus - Binding across time (trace conditioning)? -link across time --> *receiving context and item information and creating a new episodic memory. --> *should light up in recollection studies PERIRHINAL CORTEX: item/object processing - Item familiarity --> if the region has seen something it should see it more quickly the second time. supporting familiarity judgments - Conceptual Implicit memory - study windsurfer, and give me an example of a sport it comes to mind more readily. - object perception --> identify a face--> 'what' ventral stream PARAHIPPOCAMPAL CORTEX: context processing- Recollection of context -->- Scene processing--> 'where' dorsal stream

Place Cells

(e.g., O'Keefe & Dostrovsky, 1971) Place Cells - found in the hippocampus (CA1, CA3, EC, DG, subiculum, visual cortex) - cells that response only when an animal is in a specific location in space- observed in various environments (e.g., open boxes and circular tracks) - cells will 'remap' when put in a new space (e.g., fire to different location in a round vs square box) specific to that environment- many (maybe all) place cells are complex (e.g., fire more when object is missing, fire when about to turn left vs right in a T-maze etc) - fire when going to a specific state and going in a particular way - many cells also respond to non-spatial dimensions like auditory frequency IMPLICATIONS: --> not just coding for place (?Feature conjunctions? Continuous dimensions?) - the idea that when I am in this location at this time it will fire

Recurrent concussion's

* Concussions are associated with an increased likelihood of Mild Cognitive Impairment (MCI), reports of memory impairments, and earlier onset of Alzheimer's disease (the more concussions the more likely you will get it) later

COVID and Memory

* Severity related impairments in fluency, processing speed, WM and LTM recall (less for recognition) --> memory/executive deficits (frontal lobe, MTL)? --> had a drop in delayed recall and had some impairment, and those who were hospitalized had it worse. Not much of an effect in recognition. * Reductions in parahippocampal gyrus and lateral orbital frontal cortex * increased diffusion (loss of white matter integrity) across olfactory regions * changes led to a decline in executive function trail-making test (few other measures).

Brain Changes in Aging- cross sectional studies

* age related declines in lateral prefrontal cortex and hippocampus, but little decline in other regions like the occipital cortex or entorhinal cortex. DECREASE CHANGE - lateral prefrontal cortex is slowly decreasing in size as we age - hippocampal volume remains constant until age 40, then starts to decline in volume. DOESN'T CHANGE - entorhinal cortex did not show the decrease in volume - primary visual cortex has no effect, so it doesn't change

Brain/Behavior Correlations in Aging

* hippocampal atrophy is correlated with explicit memory declines (e.g., Rodrigue and Raz, 2003). * white matter hyperintensities are related to explicit memory declines (e.g., de Groot et al., 2000). --> hyperintensities: white spots on scan mean more dead tissue in white matter tracks- change in hippocampal volume and more atrophy, the more white matter volume will decrease

Cellular Summary

- Cortex: Hebbian learning within hierarchical sensory streams (perceptual -->semantic knowledge)- hierarchies that go from perceptual t semantic knowledge - Hippocampus: binding of event components from the EC into a sparce orthogonal representation in DG-CA3-CA1, which is linked back to the event components in EC --> different circuits and in EC there are boundary cells, head direction and speed and grid cells and they are all somewhat perceptual but once you get into the hippocampus proper, the place cells and concept cells are more sophisticated like- 'boundary', 'head direction', 'speed' and 'grid' cells (building blocks for hippocampal representations?) - 'Place' & 'concept' cells (complex conjunctions of event features)

what's the difference between Explicit and implicit memory test. How can you tell the difference in tests

- EX- requires consciousness, deliberate, try to use memory to answer this question 'can you tell me what words were in the study lists' - IM- automatic, unconscious, never tells them to use memory, but tells them to do something with the material 'flash word on the screen and tell me what you see'

Implicit vs Explicit Memory

- Explicit memory tests - tasks that explicitly instruct subjects to use memory (e.g., recall, recognition)- Implicit memory tests - tasks that do not explicitly instruct subjects to use memory(several different types of implicit memory -sometimes referred to as 'priming') * if you activate a representation of the word 'ellipse' for example, you have primed that activation and so when given the word fragment it comes to mind readily.

threshold theory/ signal detection theory connection with recollection and familiarity

- Familiarity--> assess how familiar the item is and makes some judgments based on the strength of the item (signal detection theory). - Recollection --> sometimes you recollect specific details and sometimes you are randomly guessing (Threshold Theory)

The cellular basis of memory

- Hebbian learning - A synapse between two neurons is strengthened when the neurons on either side of the synapse (input and output) have highly correlated outputs. (Cells that fire together wire together). - Hierarchical organization of the cortex - posterior --> anterior -- features to simple feature conjunctions to abstract objects- increase the extent that they are correlated and fire together, strengthen the association and account for the learning rule. Take a simple rule, embedded them in a hierarchy, and then you have a system that lets you learn associative information. ---------------------------------- The Hippocampal Circuit - Entorhinal cortex (EC) --> dentate gyrus (DG) --> CA3 --> CA1 --> EC - The hippocampus supports encoding by forming sparce and orthogonal representations (episodes or indexes) through 'pattern separation', and supports retrieval through a process of 'pattern completion' - neocortex (parietal, prefrontal, temporal) --> feeds into parahippocmapus, and perihinal cortex --> feeds into the Entirihonal cortex --> tricenaptic loop dentate gyrus(DG) --> CA3 --> CA1 --> goes back to Entirihnal Cortex --> make a sparse representation of the event, compress it and give it to a small number of neurons in the hippocampus. Take the information I learned in the hippocampus and teach it to how to uncompress/retrieve information. We have an encoding and retrieval phase. - Encoding phase is trying to take the memory and make a unique representation. The entorhinal likes it when new stuff is presented, the dentate gyrus doesn't like to fire very much, so they are sparse and the idea is that these neurons are important in representing the episode in every unique way and use them to make a representation of the event. Important for creating memories for episodes. supports retrieval. - Retrieval -Pattern completion: project to CA3 and CA1, they are very noisy.

Summary of brain areas and recollection, recall and familiarity regions

- Hippocampal damage (H) - disrupts recollection - Perirhinal damage (PRC) - disrupts familiarity - H + PRC damage - disrupts recollection and familiarity --> if legion hippo and perirhinal - knock out both R and F --> if legion hippocampus - severe deficit in recollection but familiarity is not impaired --> if legion perirhinal- selective impairment in familiarity but recollection is fine

Trace and Decay conditioning

- Neurogenesis is increased by extensive hippocampal dependent learning (i.e., trace, but not delay conditioning. - delay (overlap with tone)--> don't need a hippocampus for this - trace conditioning --> need a hippocampus and a memory trace to link the tone and shock - if the hippocampus is active, we rescue the neurons and they are engaged in a memory circuit. If you don't use hippocampus to learn it, the cells are not rescued as much. Related to type of learning

Neurogenesis in the DG

- New cells in the rat hippocampus - - dentate gyrus has new cell growth constantly and grows into mature cells. Born in dentate gyrus but don't stay there for long - Cells mature within a few weeks

Dual-Process Theories of Recognition: Recollection and Familiarity

- Recognition memory judgments can be based on recollection or on familiarity - Recollection (R): a relatively slow search process whereby qualitative information about a prior event is retrieved (e.g., when, where event occurred etc). --> sometimes you get the information, sometimes you don't but you are guessing - Familiarity (F): a relatively fast process whereby familiarity or a 'sense of recency' is used as a basis for recognition (i.e., the item seems familiar, so it probably was studied).

Multiple Types of Memory

- STM--> visual, central executive, phonological - LTM --> Explicit (recall [Frontal Cortex], recognition --> recollection [H, PH]) Familiarity [PR] --> implicit memory --> conceptual ]PR], Semantic [Ant Temp], perceptual [sensory cortex], Skill [BG], Conditioning [Cerebellum]

Acute Stress and Memory

- Social stress (e.g., giving a talk to a panel of experts)- robust cortical response so stressed- Physical stress (e.g., cold pressor - holding arm in ice water vs warm water) is it impacting - encoding, - Stress period: encoding, post-encoding, or retrieval

Huntington's Disease (HD) & Parkinson's Disease (PD)

- Subcortical dementia is associated with motor problems (shaking), slowness of thought & planning problems (relatively preserved language and explicit memory) unlike Alzheimers patients - Subcortical atrophy in the basal ganglia --> Huntington's Disease -caudate nucleus --> Parkinson's Disease -substantia nigra - Both target the basal ganglia, but different structures in it

Behavioral studies of where explicit memory is 0, while implicit memory is still there.

- The Mere Exposure Effect --> prior presentation can lead to a preference for items even without any explicit memory. "which one do you like the most?" --> more likely to say a shape you had previously seen, even at only a couple milliseconds. --> dissociates implicit and explicit memory tasks - explicit memory= 0 while implicit memory is still there as they showed a preference ------------------------------------ Dorfman et al. (1995) - knew you were going for ECT treatment. Before treatment, participants see words and encode them, then test them for implicit memory after the treatment.- asked to do stem completion vs. cued recall for words encoded just prior to ECT * Retrograde Amnesia for explicit memory --> if asked about earlier words, amnestic for words just prior to ECT, cant recall so impaired * no RA for implicit memory --> for stem completion priming, the performance is better and priming is shown. No evidence that ECT wipes out implicit memory. IMPLICATIONS: --> dissociates implicit/explicit --> knock out explicit memory= 0 but no impact on implicit memory

Alzheimer's (AD)

- a progressive, degenerative disorder associated with profound memory and language impairments. --> drop in memory seen first and then decline in language ability. • MiniMental State Exam score of < 24/30 is suggestive of potential AD • Rapid decline in memory ability • Death 3-10 years after onset (early diagnosis to severe)

which of the following is correlated with increased likelihood of dementia?

living close to a highway

How would you test an auditory implicit memory task?

- done visual distraction paradigms OR - listening to a friend in a noisy a noisy room (given words in a quite room, and run an auditory perception task tests. Given words in a quite environment and then at time of test you test them in a noisy environment, and at very low levels present the words and told to identify them. - priming effects should be in the auditory cortex should light up- if you prime faces, you prime the fusiform face area and if you prime places, the Para hippocampal place area will be primed. - this type of implicit memory is sensory in nature

could you have an explicit memory test that is contaminated by implicit memory?

- given an explicit test (give me all the words in a study list that started with 'M-O-T') and you can easily just guess 'motel'

How do I know if someone has normal aging or pathological aging?

- if someone has AD, they will have STM, Semantic, and conceptual implicit memory problems

What is an example of memory cuing

- learn card location associations during the presence of a context odor. - Old or new odor presented during slow wave sleep *odor during SWS increased memory *odor while asleep led to hippo activation- lead the hippocampus to remember it studied something in the context

what's the evidence that the modal model doesn't work in regards to its LTM components.

- lots of dissociations in implicit and explicit LTM telling us we need at least two things.--> LTM can be dissociated neurally and behaviorally into explicit and implicit memory.

Auxiliary Assumptions in Tulving's episodic and semantic knowledge and its modification

- only humans have episodic memory (i.e., ability to travel back in time) --> complaints: bird can remember what was stored and when so it can eat it on time. They seem to have episodic memory Limitations - how to account for skill learning & perceptual implicit memory?

On what types of cognitive tasks do amnesics perform normally?

- perceptual abilities - phonological STM - (e.g., digit span) - Semantic memory (eg. language) - Skill learning (e.g., the tower of Hanoi puzzle, mirror drawing)

They have memory problems thinking they have Alzheimer's, How do you determine whether they have it or not? Can't measure using scanners- what would you look for to see if they have it?

- perform familiarity test, if they are aging normally it should be okay, if they show impairment they could have Alzheimer's - conceptual implicit task - should be impaired in Alzheimer's or - test semantic knowledge, if they perform fine for healthy aging, they would be aging healthily, but if they show impairments they could have AD

Why does sleep help in memory? explain using theories?

- reduces interforce - consolidation- moves stuff to the cortex during sleep - synaptic homeostasis theory- brain becomes more active during the day so at night, the things that weren't well encoded will be compressed and removed.

Preston & Gabrieli (2008) - encoding activation related to context cueing and recognition (NEUROIMAGING DATA)

- see if repeated array leads to a decrease in response time or recognition test (know that it was repeated) - Repeated arrays led to a reduction in perirhinal activation (this region was not related to recognition memory) • Recognition memory was related to hippocampal activation (this region was not related to spatial cueing effects) --> The perirhinal cortex is involved in context cueing? (inconsistent with lesion data!) - Legions were so big so couldn't tell what specifically was light up. --> MTL is critical for context cueing, but don't know for certain whether is it Hippocampus or PRC? --> implicit memory is supported by regions outside the MTL.

Dentate Gyrus

- sparse, doesn't activate a lot, generates new neurons every day - should be important for episodic memory

based on the Greeks does stress impact encoding, post-encoding or retrieval.

- stress at time of ENCODING: stress can either enhance or disrupt encoding (the critical factors are not yet known) a lot of individual difference - POST-ENCODING STRESS: stress increases memory for recently encoded information - stress at RETRIEVAL: stress disrupts memory retrieval

imagine you have two old people who come into the clinic and they have memory problems thinking they have Alzheimer's, How do you determine whether they have it or not? Cant measure behavior- what would you look for to see if they have it?

- tau fibers- entorhinal cortex change - if they have atrophy then they have problems - temporal lobe/cortex shouldn't show any difference, you can also look for cell death too

modification for the auxiliary assumptions in Tulving's episodic vs semantic memory

- the serial in / parallel out model (Tulving, 1995) - it's a three-layer cake, when you experience something, you process it with perceptual and procedural characteristics (how we see it), then semantically (what does it mean), and if we are lucky we go to episodic memory and glue everything together. When inputting information it goes through three levels but when retrieving we can independently retrieve information from either of the modes (episodic, vs semantic vs perceptual/ procedural)

why does generation helps recognition (explicit memory), but seems to hurt perceptual implicit memory?

- we are better at identifying the words we read because our visual system/cortex saw them and perceived them, and the perceptual identification and visual memory are better the second time around because the neurons in the visual cortex are better at identifying them the second time. - For the generated words, we never saw the word 'hot', we only produced it in our head, so our visual system didn't get practice seeing it, so it will not show priming.

What is memory contamination? and how can it be avoided and measured?

- when giving an implicit memory task, some of the subjects knew this was a memory task and so they might use explicit memory to find solutions to these stems (would find better memory for deep encoding) HOW IT CAN BE AVOIDED/ MEASURED - ask post-test awareness questionnaire (e.g., "what was your strategy for completing the words?") -aware/unaware groups - how did you do the test? - disguising what the point of the experiment is

Summary effects of retrieval and encoding manipulations

--> Double dissociations indicating that R and F are distinct --> R - slower, attention demanding, preferentially benefits from elaborative encoding --> F - more perceptual, sensitive to fluency and response criterion manipulations

Trace and Delay conditioning (implicit memory?) - will he lose this association

--> depends on the type of conditioning that occurs A conditioned stimulus (CS, e.g., tone) is paired with an unconditioned stimulus (US, e.g., an air puff) that produces a response (e.g., eye blink). The CS itself will eventually elicit the response. • In delay conditioning the CS overlaps with the US -> get tone and get air puff at the end of the tone. • In trace conditioning there is a delay (~1 second) between the CS and US --> tone goes off, and then a puff of air is given a second later. Hippocampus is implicated Example study of Conditioning Clark, Manns & Squire (2002) - conditioning (tone - air puff) in MTL and controls while watching a movie * Delay conditioning was normal in MTL amnesics * Trace conditioning was impaired in MTL amnesics. IMPLICATION: --> Inserting even a very brief delay (1 second!) between CS and US makes the task MTL dependent --> delay is within STM, and tells us that if the stimuli co-occur in time, something in the brain can learn that and we don't need the hippocampus anymore. If the two things are separated by a delay, of even 1 second, you need the hippocampus to tell you that the two stimuli go together ---------------------------- Cheng et al 2008 - fMRI during trace and delay conditioning in healthy subjects RESULTS: * cerebellum was involved in both trace and delay conditioning, whereas the hippocampus was most involved in trace conditioning IMPLICATIONS: **--> Hippocampus is critical for trace, but not delay conditioning

What is an expeiremnet that shows memory replay in humans?

--> rats- recorded cells during maze running and during subsequent sleep. - Memories are replayed during slow-wave sleep- (memory replay)

double dissociation using the Remember/Know procedure (Tulving, 1985)

-Gregg & Gardiner (1994) HOW:- Study: words (visual or auditory) see words or hear words and encoding them - Test: given words on a screen (visual), asked if R/K/N recognition responses- asking if memory is better for the words you saw or heard? RESULT: * Perceptual match increased F, but not R --> if the modality is the same you are better, but for recollection responses, it does not matter whether you heard or saw it --> But judgment on familiarity increased for the same modality words. So if I see it in the beginning and see it later on familiarity is higher. IMPLICATION: --> F relies more on perceptual information than does R --> Sense of familiarity depends on the sensory overlap between what you studied first and what you're tested on. Whereas your ability to recollect details doesn't really matter. --> dissociate F from R (familiarity can move around, recollections stay the same) ---------------------------------- Parker & Walker (1992) - effects of aging on memory HOW: - study: list of words- test: R/K/N recognition responses judgments RESULTS: * Aging reduced recollection but not familiarity --> R is more susceptible to aging than Familiarity --> older people were terrible at remembering lists, but for familiarity, they were identical to young subjects IMPLICATION: --> dissociate Recollection from Familiarity --> recollection doesn't survive the aging process, but familiarity is preserved. mess up with recollection, but leave familiarity intact- this study and the one before it form a double dissociation between F and R

Theories of sleep and memory

1) 'Interference Reduction' (Jenkins & Dallenbach, 1924) - sleep reduces the amount of new interfering information encoded into memory. - reduces proactive and retroactive interference 2) The 'consolidation hypothesis' - (e.g., Squire & Alvarez, 1995; Stickgold, et al 2000) -sleep leads fragile memory traces to be replayed and thus consolidated in the cortex. (Note - could also be synaptic consolidation) - memories being shuttled to the cortex, however, it seems to be doing it more quickly than the mechanism leads us to believe, so it may be synaptic consolidation. 3) The 'synaptic homeostasis hypothesis' - (e.g., Tononi & Cirelli, 2006) - wakefulness leads to an increase in synaptic strength and activity, such that sleep is needed to down-regulate activity to facilitate efficient learning of new material. The weak connections are lost during sleep, increasing the signal-to-noise ratio. - synaptic activity is low in the morning but as the day progresses, cortical activation increases, we know neurons don't learn very well when they are firing a lot, once the day progresses you are not very efficient, you need sleep to slow down activation where it can learn more efficiently. Reduce activation of the system, and things that are well learned will survive, and things that weren't well encoded will be compressed and removed.

Give an example of a study that tests sematic knowledge

1) - "The Crovitz Test" - given the word 'letters' and told to recall an experience of the word when in High school vs grade school. Asses specific periods of time and compare them to other people who are normal. 2)- "Dead or Alive Test"- presented with faces/names of people who died at different time periods, asked if they are Dead/Living? + what did they die from 'natural causes'? + when? 3) - "Autobiographical Memory Interview"- Autobiographical and personal semantic memory from childhood, midlife and adulthood. Cued to describe several memories from each period and scored for the number of details. - bob hope's father was a fireman

Perirhinal cortex dependent

1) Conceptual implicit memory 2) Object perception

Memory in HD and PD

1) Explicit memory - NORMAL - recall and recognition is relatively preserved early in disease. They are aware of the progression of disease. 2) Skill Learning - IMPAIRED e.g., Saint-Cyr, Taylor & Lang (1988) * PD and HD patients did poorly on Tower of Toronto task, but were normal on recognition and recall --> PD & HD disrupt skill learning --> However, don't get better at tasks with more practice. Take them the same amount of time to perform the task. - skills learning is selectively impaired, which is the opposite of amnesics. Double dissociation. 3) Perceptual implicit memory -NORMAL e.g., Shimamura, Salmon, Squire, & Butters (1987) * HD were normal on stem completion- linked to visual cortex, and that tissue isn't disrupted and so they show normal performance e.g., Bondi & Kaszniak (1991) * PD were normal on stem completion--> preserved perceptual implicit memory 4) Conceptual implicit memory Shimamura, Samon et al. (1987) - free associate task -NORMAL - study: needle-thread - test: "needle- ______" * HD were normal--> preserved conceptual implicit memory. More likely to the prime thing you studied before. 5) Short term memory - NORMAL e.g., Skell et al., 2001* PD patients exhibited normal performance on short term verbal memory tasks --> Relatively preserved STM - digit span normal 6) Semantic memory- SOME IMPAIRMENT Cotelli et al., (2007) - action and object naming HOW: - name the object, or describe the actions associated with the object- lemon- being squeezed- so semantic information about what the thing does/ what you do with the thing. RESULTS: * PD deficits in naming, particularly for actions --> semantic memory deficits, particularly for action related objects - unimpaired in object naming, but trouble in naming the action. - high-level cognition is intact, so knowledge of the world is okay, but there are subtle disruptions related to action knowledge. - suggest that our knowledge of the world isn't all abstracted and moved outside of the neural tissue that was involved in learning the information

Memory in AD

1) Free recall * severe recall deficits in AD 2) Recognition-Dalla Barba (1997) - remember/know recognition * Severe deficits in recollection and familiarity in AD --> AD affects all forms of explicit memory 3) Skill learning e.g., Deweer, Pillon, Michon & Dubois (1993) * close to normal performance on mirror reversed reading --> procedural memory is preserved in AD- motor cortex wasnt attached in AD patients 4) Percepual implicit memory e.g., Partridge, Knight & Freehan (1990) * normal stem completion --> perceptual implicit memory is preserved in AD, (because of preserved visual cortex) 5) Conceptual implicit memory e.g., Salmon et al. (1988) - word association learning in AD HOW: study: needle-thread test: needle-______ 'first word that comes to mind' RESULT: * AD performed more poorly than healthy control subjects--> conceptual implicit memory is impaired in AD (perirhinal cortex is implicated and it is impacted) 6) Short term memory* AD patients exhibit deficits in digit span tasks--> Short term memory is impaired in AD (frontal cortex damage causes these impairments) 7) Semantic memory - Adlam et al., (2006) object naming and matching to function or action - object naming is severely impaired and semantic knowledge * AD impaired on naming and all semantic matching tasks - wouldn't be able to name objects or identify that you can use a fork instead of a potato masher --> semantic memory is impaired in AD --> not just a language problem, they genuinely don't know how to name it or the semantic problem

Three MTL subregions

1) Hippocampus 2) Parahippocampal Cortex (posterior) 3) Perirhinal Cortex (anterior) --> conceptual implicit memory --> 2 & 3 in Parahippocampal Gyrus

Summary of Ways to reduce the effects of aging on memory

1) Maintain cardiovascular physical activity 2) Stay intellectually engaged 3) Sleep 4) Pollution 5) Maintain brain-healthy diet 6) Bilingualism 7) Minimize chronic stressors

Ways to reduce the effects of aging on memory

1) Maintain cardiovascular physical activity (Colcombe et al., 2003) e.g., Erickon et al., (2011)- 120 older adults assigned to aerobic (e.g., 40 min walk, 3 days a week for 6-12 months) or stretching conditions (Yoga) RESULTS: * Exercise reversed the age-related decline in hippocampal volume - exercise led to a bigger hippocampus, while the teachers hippocampus declined. * Increased hippocampal volume, which was related to an increase in short-term spatial memory (similar effects have been observed in LTM, in young and middle aged, as well as changes in frontal cortex and executive function) - healthy heart = healthy brain - prevents strokes etc. ----------------------------------------------------- 2) Stay intellectually engaged (Albert et al, 1995) Cognitive Training (note the 'Luminosity' lawsuit)Simons et al., 2016 (ACTIVE Clinical Trial) HOW: - 2800 older subjects in 3 training groups (Reasoning, Memory (techniques to remember), Speed-of-processing (how quickly can you do tasks)) for 10 sessions (60-75 min each- including instructions on how to apply the training to real-world) vs a Noncontact Control group (matched on age, bit didn't get training) - Booster training after 2 and 5 years- Followed subjects for 10 years RESULTS: * Long lasting training benefits * But limited to training tasks* Increase self reports of cognitive improvement (people said that their function was improved), but no objective improvements of daily function. - Doesn't tend to generalize, only help with specific tasks you practiced - If you got memory training, you get better at memory task, but no better at reasoning or processing speed, so only get better at what you trained for. ------ Engaging Video Games - 'gamification' of cognitive training (Mansor et al., 2020 meta-analysis) *Improves Updating (working memory) but not in Delayed memory - perhaps extensive engaging computer games targeting a broad set of cognitive skills would work better? ** Could cognitive training effects be a Placebo effect? - The expectation that the training will lead to an improvement can lead to an improvement (Boot et al., 2013; Foroughi et al., 2016, but also se Tsai, 2018) --------------------------------- 3) Sleep - Chen (2019) - there is a positive correlation between memory and # of hours sleepHolth et al., (2019) - sleep may slow the onset of Alzheimer's- monitor tau in human cerebral spinal fluid in adults (lumbar catheters), people are 30 to 60 years of age, who were monitored during one night of normal sleep and one night of sleep deprivation RESULTS: * sleep deprivation led to an increase in tau and beta-amyloid IMPLICATIONS: --> a failure to clear tau during sleep may be related to AD? - sleep is sweeping up the garbage that may have built up and led to the disease --------------------------------------------- 4) Pollution? Chen, Kwong et al., (2017)- N=2.2million 55-85years (Ontario, CA) - proximity to major roadway and its relationship to dementia RESULTS: * living <200m from a major roadway was related to dementia * Controlled for socioeconomic status etc (largest in 'never movers') IMPLICATIONS: --> toxic effects of ultrafine particles? noise? lack of sleep? ---------------------------- 5) Maintain brain-healthy diet (Morris, 2002; 2003)-unsaturated fats (fish, olive oil), antioxidants (citrus, dark skinned fruits and vegetables) 6) Bilingualism (Bialystok, Craik, Freedman, 2007)- bilingual speakers had delayed onset of AD by 4 years (see Anderson, Hawrylewicz & Grundy, 2020 for meta-analysis) 7) Minimize chronic stressors (Sapolsky, 2002)? Largely speculative

Neurogenesis

1) New cells are generated in the DG of the hippocampus (probably in humans? ideally suited to support episodic memory) 2) Neurogenesis is related to memory (e.g., stress, depression, aging, exercise antidepressants etc.) - ? can injection of stem cells or molecular therapies (neurotropic factors) reverse memory declines?

What cognitive functions are preserved in amnesia?

1) Perceptual abilities (e.g., visual acuity, color perception etc.) - do not need hippocampus 2) Phonological short term memory (e.g., digit span) --> can hold on to short term memory 3) Semantic memory (e.g., knowledge, language and IQ) 4) Skill learning (e.g., the tower of Hanoi puzzle, mirror drawing) Cohen et al., (1985) --> the tower experiment, when they did it the second time they got faster, no explicit memory of doing it, but you remember how to do the task

There are various ways of measuring R and F

1) Remember/know (Tulving, 1985) - subjects can report when they 'remember' and when they just 'know' (familiarity) an item was studied. require them to introspect and tell you if they remember the details or if they know it was studied based on familiarity 2) Process dissociation (Jacoby, 1991) - 'item recognition' relies on both R & F, whereas 'relational recognition' relies more heavily on R--> more objective approach: relational recognition - was it in list number 1 or 2, left or right hand side, you can ask subjective questions that if answered correctly tells you if they actually remembered. Subjects need to provide more subjective details --> if you compare relational memory and it behaves differently from item recognition then there is evidence that there is a distinction between recollection and familiarity 3) ROC (Yonelinas, 1994) - R & F can be estimated based on the shape of the ROC (i.e., confidence judgments) --> based on the shape of the ROC you can infer what the subject is doing with recollection and familiarity

Hippocampal dependent (need the hippocampus)

1) Scene Perception 2) Trace conditioning --> delay between stimulus and response 3) Precise visual STM - identity exactly what color it was

Sleep Summary

1) Sleep before and after learning slows explicit memory forgetting 2) Sleep can improve implicit memory 3) Sleep benefits occur within 60-90 minutes 4) The roles of SWS/REM sleep are not clear 5) Learning can lead to 'replay' during sleep/wake 6) Cuing during SWS can improve memory?

Current Challenges to the Memory Systems Models

1) Some forms of implicit memory can be supported by the MTL (e.g., conceptual, spatial and trace conditioning) --> not so simple that MTL is only for explicit memory 2) Some forms of perception and STM can be supported by the MTL --> can't simply say the STM is in the cortex and LTM in the hippocampus 3) Specialization within the MTL (hippo vs perirhinal cortex) --> depend on where you legion the person

Neural Basis of Perceptual Implicit Memory:

1) Visual priming involves the visual cortex 2) Priming is related to a decrease in activation (more fluent processing?) 3) No consistent left vs right hemisphere differences 4) Also involves material-specific regions (e.g., fusiform for faces)

Describe an experiment with healthy subjects that shows that implicit and explicit memory dissociate.

1) Word fragment completion HOW: - Study: list of words (intentional encoding 'try to remember these words') - Tested (1 hour or 1 week later): recognition (do you recognize this word from the study list) or word fragment completion (e.g., t__ui_a for tequila) complete it with the first word that comes to mind. RESULTS :--> forgetting rates are slower for perceptual implicit memory than for explicit recognition --> recognition declines over time IMPLICATIONS: --> implicit and explicit memory tests dissociate - if I test you a week from now on the fragments, this unconscious implicit memory will still show, even when your ability to recognize the words has diminished. - A delay between one hour vs days has a big effect on explicit memory, but implicit memory sticks around for a long time.

Behavioral study that dissociates explicit and implicit memory?

1) Word fragment completion e.g., Tulving, Schacter & Stark (1982) HOW: Study: list of words (intentional encoding 'try to remember these words') - Test (1 hour or 1 week later): recognition (do you recognize this word from the study list) or word fragment completion (e.g., t__ui_a for tequila) complete it with the first word that comes to mind. RESULTS: --> forgetting rates are slower for perceptual implicit memory than for explicit recognition --> recognition is better after an hour is good, but it declines over time IMPLICATIONS: --> implicit and explicit memory tests dissociate- fragment completion did not show any effects on delay - if I test you a week from now on the fragments, this unconscious implicit memory will still show, and pop in your mind a week later even in situations when your ability to recognize the words has diminished. - seeing a dissociation, so a delay between one hour vs days has a big effect on explicit memory (explicitly remember what happened a week ago), but this implicit or unconscious memory sticks around for a long time. --------------------------------------- Mulligan (1998) HOW: - Study: study list of words with full attention vs words + secondary task with divided attention - Test: implicit fragment completion vs explicit fragment completion (cued recall) told to use the words to remember what words was. (trying to use memory vs going with your gut) RESULTS: - for implicit memory, it did not make difference whether you attended to the list or not, reading it is sufficient to get it in at an unconscious level. For explicit memory, however, whether you attended to it or not, the study made a difference. - dissociation where moving explicit memory around, while leaving implicit memory intact. IMPLICATIONS: --> implicit memory does not require attention

Types of Amnesic Patients simplified list

1) lesions 2) posterior cerebral artery infarct (stroke/blood clot) 3) hypoxia (brief loss of oxygen) [selective Hippocampal damage in mild cases] 4) Fornix damage 5) brain infection (e.g., viral encephalitis) [extensive MTL] 6) Korsakoff's syndrome (Thiamin deficiency)7) ECT (electro convulsive shock therapy) 8) Traumatic Brain Injury (e.g., car accidents) 9) Transient Global Amnesia

Types of Amnesic Patients

1) lesions (e.g., injury, surgery...) [brain regions: selective] 2) posterior cerebral artery infarct (stroke/blood clot) - plumbing for brain is lateralized --> if the posterior cerebral artery gets blocked, the left hemisphere and hippocampus will be impacted 3) hypoxia (brief loss of oxygen) [selective Hippocampal damage in mild cases] --> hippocampus uses a lot of oxygen, and so if I get a heart attack, and oxygen levels are low, the hippocampus will be the first to get impacted. selective region specifically in the subregion, hippocampus CA1. 4) Fornix damage - fiber track linking hippocampus to the thalamus caused by surgery or stroke (deficits similar to those see with hippocampal damage) --> deficits are like hypoxic patients and cause dense amnesia 5) brain infection (e.g., viral encephalitis) [extensive MTL] --> swelling of the brain, extensive temporal lobe atrophy and cell death in the medial temporal lobe. The most densely amnesic patients. 6) Korsakoff's syndrome (Thiamin deficiency) - related to alcoholism, amneisa related to vitamin thiamin deficiency- dense amnesia plus executive deficits [thalamus, frontal cortex..] 7) ECT (electro convulsive shock therapy)- treatment for depression and bipolar disorders -older methods led to memory impairments [brain areas - ???] --> you can electrically restart the brain and some older methods led to memory loss. The brain areas the are affected are too broad to pinpoint. 8) Traumatic Brain Injury (e.g., car accidents) memory plus executive impairments [frontal+MTL] --> executive important (frontal lobe legions) --> memory problems because of the damage to medial temporal lobe as the brain sloshes around when you are in an accident, sharp bones around the eyes damage it. 9) Transient Global Amnesia - a sudden onset of a selective antero/retrograde amnesia that typically recovers <24 h • Various causes: acute emotional stress (e.g., death of a loved one), acute physical pain (e.g., dramatic temperature changes), sexual intercourse,..... Bartsch et al., (2006)- high resolution MRI and memory in 41 patients • Hyper-intensities observed in the hippocampus (CA1), related to recall and recognition memory impairments • Hyper-intensities and memory impairments resolved after 6 months.

you are put in charge of the national institute of aging budget and it is your job to shape the landscape of scientific research on memory and aging. 1. Describe one current effective intervention that reduces the risk of memory loss 2. Explain what scientific advances you think are needed to reduce memory deficits in aging. Justify your answer

1. One current effective intervention is mataining cardiovascular physical health. A healthy heart means less likelihood of strokes or heart attacks which ultimately helps the brain as it reduces atrophy and thus damages the brain. As a result, exercising is very important as it has been shown to reverse the age-related volume decline often seen in the hippocampus. 2. some scientific advancements needed to reduce the memory deficit in aging include finding ways to combat tau tangles as they are implicated in the clinical symptoms seen in Alzheimer's patients including memory loss. Finding ways to reverse the tangles or reduce their prevalence can help patients, especially those diagnosed with or have an increased likelihood of developing AD, Monitoring the tau fibers in an individual's body may help with early detection or even treatment. Amyloid plaques are also implicated and understanding their role in the condition could help scientists look for treatment methods.

example of perfect crossover dissociation for implicit and explicit memory

2) Perceptual Identification e.g., Jacoby (1983) HOW: - Study: read some words vs. generate words ("hot" vs. "the opposite of cold is..?") - Test: recognition vs. perceptual identification (e.g., flash words for 10ms, "identify words") -wondering whether we are better able to identify the previously studied words and whether the prior study event primed us. RESULTS: - after delay for the people who recognized the word, you are better at recognizing the generated items, for perceptual identification we are better at completing and visually identifying the words we had read before than the items they generated. * perfect crossover dissociation IMPLICATIONS: --> dissociation between implicit and explicit tests --> generation helps recognition (explicit memory), but seems to hurt perceptual implicit memory (why?) --> why -we are better at identifying the words we read because our visual system/cortex saw them and perceived them, and the perceptual identification and visual memory are better the second time around because the neurons in the visual cortex are better at identifying them the second time. - For the generated words, we never saw the word 'hot', we only produced it in our head, so our visual system didn't get practice seeing it, so it will not show priming.

Things that Enhancing Memory and evidence

4. Behavioral manipulations/interventions •Sleep (implicit/explicit; pro/retroactive; replay, cuing) •Exercise (young/old) •Stress Reduction •Stay mentally active (cognitive training?) •Bilingualism 5. Systemic manipulations •Diet (Mediterranean, low fat) •Drugs (Antidepressants, stimulants, cholinergics, Gingko Biloba) •Brain Stimulation (temporal/parietal)? --> activate brain circuits

Provide a real-world example of the mere exposure effect.

A real-world example of the mere exposure effect can be seen in marketing. When we turn on the television and an advertisement is played we are being exposed to an array of products. It does not matter if we are attentive to the commercial or what it is saying, we are subliminally getting exposed to the company's products. As a result, the next time we go to the store and we're deciding on a brand of water to buy, our brain will bias us to choose a familiar name or product. We will likely show a preference effect for the previously heard brand names as we were exposed to them before and thus familiar with them. Merely exposing ourselves to something makes us like it even if we have no explicit memory of seeing the commercial.

The Modal Model (e.g., Atkinson & Shiffrin)

ADVANTAGES •The model can account for dissociations between STM and LTM --> can create an amnestic patient by lesioning the LTM box DISADVANTAGES:•But it can't account for the behavioral or neural dissociations seen within/ different types of LTM (e.g., implicit vs explicit, amnesia etc.) --> doesn't take into account the neural dissociation between explicit and implicit LTM --> model can't handle this because you can knock out implicit LTM, but leave explicit intact, model cant explains this. Model has been disproven --> test question: modal model doesn't work in regards to ...... NEW THEORY: --> Memory Systems' Accounts of Amnesia- the MTL supports an explicit LTM, whereas the cortex supports implicit LTM and other cognitive abilities (STM, IQ etc.)- specialized memory system MTM system that supports explicit LTM

Healthy Aging

Age-related decreases in ___ after age 20 1) speed of processing- how fast are you at doing cognitive tasks 2) working memory 3) long term memory Preservation of: 1) World knowledge- vocabulary

Age related memory impairments in Alzheimer's

Alzheimer's- entorhinal, hippocampus, frontal, temp. parietal, (cell death) - PRESERVED: perceptual implicit, skill learning - IMPAIRED: STM, Recall, Recognition, familiarity, conceptual implicit, semantic

Place cells- Place fields

Barns et al., (1997). HOW: Place fields in old/young rats running a maze at two different times in the day. (each cell is color coded) - learn the maze then brought the next day in the same environment. RESULTS: - The young rats remember and the cells light up in the same location- in older rats, their spatial memory is worse and the consistency in lighting up is seen less. *Place filed maps in young rats were highly similar in the two different sessions, whereas older rats often remapped (as if they forgot the maze). IMPLICATION --> place field instability may explain the frequent failure of place recognition in elderly humans

Theories of Memory

Binding of Items and Context (BIC) - make up context and items --> perirenal cortex --> 'items' -what ventral stream --> parahippocampal cortex --> 'context' - where Dorsal Stream all lead up to entorinhal

When does neurogenesis occur in humans? - Neurological Study

Boldrini et al., (2018) -autopsy hippocampi (ages 14 to 79) *thousands of immature neurons in the DG, throughout the lifespan. --> people under 20 generate a to of new cells, but even after 80 years you are generating new neurons --------------------------------- Sorrells et al., (2018). - autopsy hippocampi (ages prior to birth to 77) * new cells only observed in first year of life. --> Still controversial (2021) reduced in aging and so far only indirectly linked to memory --> we now think that neurogenesis does occur in old age, but it is considerably less than in newborns. Decreases significantly but is not zero

Stress and neuroimaging study

Brain imaging data on stress and memory is limited, but several studies implicate the hippocampus and frontal cortex e.g., Oei, Elzinga et al., (2007) - ingestion of hydrocortisone then scanned during recognition * Reduced/decreased frontal and hippocampal activity

Stress Overview

Chronic stress •reduced hippocampal and anterior cingulate volume related to long term neurotoxic effects of cortisol •hyperactivity of amygdala (exaggerated emotional/fear memory responses) •abnormal anterior cingulate activity (abnormal frontal monitoring/modulation of fear) Acute stress ---> ↑/↓? encoding (??) mixed bag --> ↑ retention (enhance cellular consolidation? or reduce interference?) - increase in performance for retention --> ↓ retrieval

context cuing behavioral study

Chun & Jiang (1998)- "is the T facing left or right?" --> visual search task and find the t in a sea of L's and ask which side it was facing. Sometimes they will repeat the array and see whether they are better at it the second time around, so showing repetition priming. RESULT: * Response time is faster for repeated than novel arrays, even when recognition for the repeated array is at chance --> brain is remembering seeing the pattern, even when explicit memory is tested (did you see one of the tests again?) IMPLICATION: --> implicit learning of complex spatial arrays --> spatial implicit memory may need the hippocampus

Example study of Conditioning neurology MRI study

Clark, Manns & Squire (2002) - conditioning (tone - air puff) in MTL and controls while watching a movie * Delay conditioning was normal in MTL amnesics * Trace conditioning was impaired in MTL amnesics. --> Inserting even a very brief delay (1 second!) between CS and US makes the task MTL dependent -------------------------- Cheng et al 2008 - fMRI during trace and delay conditioning in healthy subjects * cerebellum was involved in both trace and delay conditioning, whereas the hippocampus was most involved in trace conditioning **--> Hippocampus is critical for trace, but not delay conditioning

Age related decreases and increases in neural activity

DECREASES * age related recollection decreases are related to decreases in hippocampal activity INCREASES - *increases in frontal lobe activity and more bilateral activity

Memory in AD

DEFICITS - free recall/ recognition/ familiarity - conceptual implicit memory - STM - semantic memory (name object not action) INTACT - skill learning - perceptual implicit memory

Disrupting Memory VS Enhancing Memory

Disrupting - 1. Interference •Proactive and retroactive interference •Forgetting functions •Changing context •False memories (similar lure) 2. Lesions •Amnesia (hippocampal [recollection] vs perirhinal cortex [familiarity]) •Temporal/parietal damage -important for phonological STM 3. Aging •Healthy Aging (H, FC, white matter, synaptic pruning) - Rec, STM •Alzheimer's (entorhinal, temporal, parietal, frontal, cell death, plaques, tangles) - Rec, Fam, STM, Semantic, concept implicit •Parkinson's/Huntington's (basal ganglia) - skill •Semantic Dementia (anterior temporal lobe) - semantic memory 4. Stress •PDSD, chronic stress, depression (Hippocampus, ant. Cingulate, amygdala and cortisol dysfunction) - LTM & WM •Acute stress (encoding [variable], post-encoding [helps remembering] & retrieval [doesn't help])

Why does the Cohen models of declarative vs procedural memory not have evidence?

Divided declarative into episodic and semantic memory. - Predicts that MTL damage will disrupt both episodic and semantic memory (contradicted by the finding that semantic memory seems relatively preserved, even when people don't have a hippocampus)

Neuroimaging study on Alzheimer's patients

Du et al., (2001) - hippocampal and entorhinal cortex atrophy in AD * AD is related to very early atrophy in the hippocampus and entorhinal cortex * Atrophy of entorhinal cortex may be observed even earlier and it is more predictive of AD --> if you have AD, quicker change in the entorhinal cortex than hippocampus ------------------------------- Cell loss (a lot of cell death in AD), Amyloid Plaques (junk DNA in between cells), Neurofibrillary Tau Tangles (within neurons and made up of disrupted proteins) - documented post mortem or with PET imaging using radiotracers (e.g., PIB for plaques, FDDNP for plaques & tangles) •Clinical symptoms are more strongly related to tangles (inside neurons) than plaques •Probabilistic risk factor Chromosome 19 apoE- if test positive have an increased liklihood •'Early onset AD' abnormalities in chromosome 21,14, 1-- coupling between behavioral and biomarkers is weak

Human hippocampal activity during a taxi cab gam

Ekstrom et al (2003) - Human hippocampal activity (depth electrodes) during a taxi cab game- simple environment they navigate and it has nine stores and you pick up a 'person' and drive them around. Monitor their brain regions RESULTS: • cells in the hippocampus (H) responded when in specific locations, but not parahippocampal (PR), amygdala (A) or frontal (F) cells--> Human hippocampal 'place' cells - responded to a specific location• cells in the parahippocampal cortex responded to specific buildings regardless of the specific location--> Parahippo 'scene' cells- respond to a specific building, regardless of location, regardless of what direction you were looking at it. ------------------------------------ Jacobs, Weidemann et al., (2013) - human grid cells? • Depth electrodes in 14 patients learning 4 invisible object-locations in open simulated space • Grid-like cells seen in entorhinal cortex (EC) hippocampus (H) and Cingulate cortex (CC) but not the amygdala, parahippocampal cortex or frontal cortex (Cx) • Autocorrelation seems necessary to clean up signal ----------------------------------------------------- Quiroga, Reddy, Kreiman, Koch, Fried (2005) - 'concept cells' - hippocampal cells that were selectively activated by different pictures of given individuals, landmarks or objects and in some cases even by letter strings with their names. - a cell that responds to whomever Halle was represented. Specialized for specific objects, scenes and people. IMPLICATIONS: - suggest that maybe all the cells are episodic cells that bind together what is relevant to you. Open Questions: - Are the specialized cells for concepts, locations, time, and edges fundamentally different? Or do they reflect cells that respond to salient features of events/episodes? (conjunctive cells, or binding cells, or episodic cells) --> they may be more general- Are these cells necessary for episodic memory? (i.e., they can be seen in tasks that do and do not require the hippocampus such as conditioning and discrimination tasks - Eichembaum, Dudchenko et al., 1999)

A patient has medial temporal lobe damage. What observations might there be in their episodic memory and semantic memory function?

Episodic memory function would be impaired with mostly intact semantic memory.

behavioral example of skill learning in Amnesic's

Even 'Nonmotor' Skill Learning (e.g., artificial grammar learning -Knowlton & Squire, 1994) HOW - Study: grammatical strings (obey some grammatical structure) of letters - Test: Grammaticality or recognition judgments, for amnesics and controls (here is a letter string, does it seem to obey the grammatical rules you saw earlier, or asked was it a term you studied earlier (recall test)) RESULTS: *amnesics were impaired at recognition, but not significantly impaired at picking out the grammatical items and make use of it even if they weren't consciously aware of it (implicit memory) --> amnesics couldn't do the recognition test (explicit memory), but they can identify the grammatical task (implicit memory), so these two processes use different functions IMPLICATIONS: --> preserved non-motor skill learning

Very briefly define and describe the difference between Recollection and Familiarity.

Familiarity refers to a relatively fast process wherein a person gets a sense of recency that is used as the basis for recognition. We use the strength of the signal we get to make our judgment about whether or not we know the item. Recollection is a slow process that uses qualitative information about a previous event to then retrieve the necessary information. We know that familiarity becomes available prior to recollection and that familiarity relies on the perirhinal while the hippocampus is implicated in recognition.

Healthy Aging and implicit memory

Fleischman & Gabrieli (1998)- review of implicit memory in aging RESULTS: * 58/69 studies showed preserved perceptual implicit memory in the aged- perceptual memory remains stable * 11/12 studies showed preserved (stable) conceptual implicit memory in the aged - 'firemen' example, can learn new conceptual information and doesn't seem to drop off in normal aging IMPLICATIONS: --> perceptual and conceptual implicit memory are preserved in normal aging

example of a lesion study that dissociates implicit memory from explicit (ie. knocks out implicit memory)? is it possible?

Gabrieli et al., (1995) - patient MS with right occipital lobe removal for intractable epilepsy RESULTS: - not completely blind, but can't see on his left side because his right hemisphere was removed. Recognition memory was fine but patient MS showed no priming effect on stem completion tasks. IMPLICATION: --> right occipital lobe damage is critical for stem priming, but not recognition memory (but - single patient???) - shaky data ------------------- Yonelinas, Kroll, Baynes, Dobbins, Fredrick, Knight & Gazzaniga (2001) HOW: - patients with right occipital damage as well as callasotomy patients RESULTS: * No deficits on perceptual implicit memory tests in any patient (e.g., fragment completion, perceptual identification etc in any impact memory task)- never able to replicate the events IMPLICATIONS: --> right occipital lobe does not seem to be necessary for implicit memory (left hemisphere supporting priming?) BOTTOM LINE: cannot double dissociate implicit and explicit memory. If you can see something, you can show priming. Need the visual cortex to support priming.

lesion study (neuropsychological) that shows a dissociation in implicit and explicit memory

Graf et al. 1984 - amnesia (patients like HM with medial temporal lobe legions, but occipital lobe is okay) HOW:- Study: intentional learning of word list - Test: free recall, cued recall (e.g., umb____ ??), implicit word stem completion (e.g., gar___??), amnesics and controls RESULTS: - amnesics have terrible free recall, were impaired in the cued recall, but did better than free recall. Word stem completion (implicit version), however, is not impaired. IMPLICATIONS: --> Perceptual implicit memory does not depend on the medial temporal lobes --> dissociation of implicit/explicit memory --> amnesics would show the word fragment completion task for studied items- need hippocampus in explicit memory, but plays no role in implicit memory

Find some evidence that explicit memory is dissociable from implicit memory. Give me a lesion study

Graf et al. 1984 - amnesia (patients like HM with medial temporal lobe legions, but occipital lobe is okay)- if you run them on tests, you would find that they had problems with explicit memory, but not implicit HOW: - Study: intentional learning of word list - Test: free recall, cued recall (e.g., umb____ ??), implicit word stem completion (e.g., gar___??), amnesics and controls RESULTS: - amnesics have terrible free recall, were impaired in the cued recall but word stem completion (implicit version), is not impaired. IMPLICATIONS: --> Perceptual implicit memory does not depend on the medial temporal lobes--> dissociation of implicit/explicit memory--> - need hippocampus in explicit memory, but plays no role in implicit memory

Implicit Memory: Visual Perceptual Learning and sleep

HOW:- visual texture discrimination (Stickgold et al., 2000) - is the dashed lined titled more one way RESULTS: * Memory improved after sleep but not after staying awake - Better at task after you sleep compared to the results right after you were tested * Maintained this improvement over several nights- has a long term benefit BUT * sleep deprivation on first night led to no memory enhancement even tested 2 days after - if you learn a task then sleep right after you are boosted, but you have to have the boost immediately after you studied it, you will not have improved memory * performance was correlated with early night SWS and late night REM sleep IMPLICATIONS: --> sleep improves implicit memory --> Both SWS & REM are important for implicit memory

grid cells

Hafting et al. 2005 - 'grid cells' in the entorhinal cortex in the rat (cells that respond when rat is in multiple locations forming a hexagonal grid pattern) - independent of the configuration of landmarks, in darkness or in the presence of visible landmarks, and independent of animal's speed and direction --> if you put landmarks, it doesn't matter and even in the dark the grid pattern will show and it just represents abstract space, and thus stable- may develop later than border and head direction cells. --> one neuron fires in a hexagonal grid shape and not represent a particular location, but creates a grid that keeps track of how far apart things are in space. - Representation of Euclidian space (2-d, 3-d space), could be used to compute self-position based on continuously updated info about position and direction. --> if the rat is listening to the information they know where they are in the environment because of the internal map that is used to represent space.

The hippocampus and 'future thought'

Hassabis et al., (2007)- had patients imagine past and future events - score responses for specific details a person would produce --> hippo lets you travel back in time to relive events but also project into the future to see what will happen and what you will do --> wanted to see if amnesic patients could generate future events that would occur RESULTS: * amnesics descriptions of future events were less detailed than controls --> controls come up with a lot of details IMPLICATIONS: --> Hippo needed to imagine events? for constructing events (either remembering the last time you went to the beach or imagining what it would be like to go to the beach for the first time). Descriptors are very telegraphic if they have hippocampal damage. ISSUE: - concern is that if we already know they have STM problems or perception, generating a description of a future event probably requires some STM abilities. So maybe these impairments are actually due to other ability deficits.

Age related memory impairments in healthy aging

Healthy aging - Hippo, frontal, white matter, (synaptic damage) - PRESERVED: Perceptual Implicit, Conceptual Implicit, Skill learning, Semantic, Familiarity - IMPAIRED: STM, Recall, Recognition

Age related memory impairments

Healthy aging - hippo, frontal, white matter, (synaptic damage) - Preserved: Perceptual Implicit, Conceptual Implicit, Skill learning, Semantic, Familiarity - Impaired: STM, Recall, Recognition Alzheimer's- entorhinal, hippocampus, frontal, temp. parietal, (cell death) - preserved: perceptual implicit, skill learning- impaired: STM, Recall, Recognition, familiarity, conceptual implicit, semantic Parkinson's/ Huntington's - basal ganglia- preserved: STM, Recall, Recognition, Familiarity,, perceptual implicit, conceptual implicit,- Impaired: skill learning, semantic (action-related)Semantic Dementia:- preserved: STM, recall- impaired: semantic

Neural Basis of Perceptual Implicit Memory?

Henson, Shallice, Gorno-Tempini & Dolan, (2002) -recognition of faces (explicit) have you seen this face before vs. fame judgments for faces (implicit), fMRI during test - all faces are not famous, but the pictures they had seen before are viewed as more famous RESULTS: * Right fusiform gyrus (face area) and left occipital regions showed less activation for old than new faces in the implicit test --> neural priming- decrease in activation for processing regions IMPLICATION: --> neural priming may be material-specific

Describe an experiment showing that recollection and familiarity reflect distinct processes.

Hintzman & Curran (1994) - Speed of R and F BOTTOM LINE: Delay helps recollection, not familiarity. Familiarity becomes available prior to recollection HOW: - Study: apple, dogs.... (singular and plural nouns) give dog or dogs - Test: Item recognition (old vs new?) (use f or R) or relational recognition (asked if word was studied in singular vs plural form? so its a recollection test) as a function of response deadline (i.e. respond before the buzzer) --> the word is presented, then a beep, then asked to recollect something right after. Sometimes the beep varies and it is a bit later. RESULT: * Item recognition (familiarity) becomes available prior to relational recognition (recollection) --> familiarity is available early on, but a fast deadline does not give us not enough time to recollect details and recognition increases as we are given more time IMPLICATION: --> F is faster than R --> dissociate R from F (delay for testing helps with recollection, but doesn't affect familiarity)

Process dissociation methods (Jacoby, 1991)

Hintzman & Curran (1994) - Speed of R and F HOW:- Study: apple, dogs.... (singular and plural nouns) give dog or dogs - Test: Item recognition (old vs new?) (use f or R) or relational recognition (asked if word was studied in singular vs plural form? so its a recollection test) as a function of response deadline (i.e. respond before the buzzer) --> use a deadline of a beeper, the word is presented, then a deadline is given by the beep then asked to recollect something right after. Sometimes the beep varies and it is a bit later. sometimes respond quickly, sometimes given time and see how performance was RESULT: * Item recognition (familiarity) becomes available prior to relational recognition (recollection) --> familiarity is available early on, but a fast deadline does not give us not enough time to recollect details and recognition increases as we are given more time IMPLICATION: --> F is faster than R --> dissociate R from F (delay for testing helps with recollection, but doesn't affect familiarity)

Fornix damage caused by surgery or stroke creates deficits that manifest similarly to:

Hippocampal damage

A Recollection Network

In addition to the hippocampus and parahippocampal cortex: - Angular Gyrus (lateral parietal cortex) --> potentially important for attention or recollective content? - Retrosplenial cortex/posterior cingulate (medial parietal cortex) --> contextual/spatial details? --> if a person has legion they exhibit a temporary form of amnesia and recover within months, making the person have spatial problems. - Medial prefrontal cortex (nPFC) --> monitoring?

Pattern separation/completion

Individual features of event A and event B- entorhinal cortex has lots of signals firing all interconnected, If I present you with two events, event A will activate neurons, and event B will activate some neurons, and there will be some overlap. We have to pattern separately by creating perse connections further into the hippocampus. If they all fire together it will strengthen synaptic connection and that is the sparse connection or the event. These clusters of neurons represent an abstract representation of event A. To retrieve I inverse map them and generate patterns to complete what I initially learned. Present some cues and see what it activates in the DG and then pattern complete what I initially learned that wasn't presented in retrieval, all the detail. - The circuitry is very good at remembering episodes- if damaged can't do pattern completion and have episodic memory problems - Dentate Gyrus can regenerate cells so important for remembering/encoding new episodes

Sleep and Memory

Inhibition of sensory and motor activity. - Cycles of Rapid Eye Movement (REM) related to vivid dreaming, and Slow Wave Sleep (SWS) every 90 minutes, with increases in duration of REM during each cycle throughout the night. --> when you go to sleep when in SWS, there are large fluctuations in activity, and there is massive synchronization of cells. When you get to REM Sleep, it looks like being awake, you lose this low wave oscillation and it turns more random. Cycles in and out and the period of REM sleep increase throughout the night.

Visual STM impairment in amnesia

Jeneson et al., (2012) HOW: - STM Color-location change detection - colored squares and then a delay of 1-6 seconds and a test probe saying were the two colors the same and whether you detected the color change. IMPLICATION: * hippocampal damage does not disrupt visual STM --> STM is not dependent on hippocampus -------------------------- Warren et al., (2015)- STM Color-location color wheel, cued to remember the color of a specific location and try to remember what the color was RESULTS: * hippocampal damage disrupts visual STM IMPLICATIONS: --> Hippo is necessary for remembering precise visual short-term memories. --> Without hippocampus cant hold on to specific detailed visual STM information

'Memory Replay' during sleep

Ji & Wilson (2007) - recorded cells during maze running and during subsequent sleep HOW: * Cortical and hippocampal place cells tracked movements on a circular maze (run)- five cells in hippocampus and through listening can tell where the rat is and cortex shows cells that are place sensitive as well RESULTS: - when in SWS, the cells fire as if the rate is asleep and reliving the experience * Found similar order activity during subsequent slow wave sleep (memory replay) IMPLICATION: --> Memories are replayed during sleep- coming back to the consolidation idea ** replay has been seen in fMRI activity in humans ** replay has been seen even in awake humans/rats

Stress and Neuroimaging studies

Kim et al (2009) PTSD and structural MRI • Hippocampal and anterior cingulate volume reductions in PTSD • Hippocampal reduction was correlated with duration of PTSD. --> Prolonged structural changes related to PTSD ---------------------------- North et al (1999) assessment of 182 survivors of the Oklahoma bombing * 36% reported PTSD symptoms at 6 months, often within the 1st week. A single stressor can lead to PTSD --> high prevalence of PTSD ------------------------------ Elzinga et al., (2003) cortisol response (i.e., a stress hormone release by the adrenal glands) to a trauma related stress script * increased cortisol baseline and increased cortisol response to trauma-specific stress in PTSD- cortisol levels never goes down to normal, they come in with raised levels compared with controls and it peaks when see trauma stimuli --> long term abnormalities in hormonal responses ---------------------- Shin et al., (2005) fMRI response to faces in PTSD * greater amygdala activity (particularly for fearful faces) - hyperactivation in amygdala so fear response even when seeing happy face * abnormal anterior cingulate activity --> abnormal frontal monitoring or modulation of amygdala fear response

The hippocampus and language

Klooster & Duff (2015)- if give subjects a word and ask them to come as many senses of the word that they can think of, like bank --> money, by the side of the river, bank a turn etc. RESULTS:*amnesics list fewer 'senses' of a word IMPLICATIONS: --> Hippo needed for language?-- helps you understand spoken communication -- challenging because the role of the hippocampus is broader than we thought - issue: could be a type of STM that's involved in generating different senses of a word

Additional roles of the MTL (beyond episodic memory)

Largely MTL independent: - MTL not required 1) Simple Perception (e.g., color) 2) Phonological short-term memory --> holding on to phone numbers 3) Semantic memory --> knowledge about the world is not impaired4) Skill learning --> tower of Hanoi 5) Perceptual implicit memory 6) Delay conditioning --> tone and stimulus are co-occurring, the brain can learn the associations without the hippocampus

Perception impairments in Amnesia (hippo vs MTL) lesion study

Lee et al., (2005) - categorization/perception in amnesia (HC=selective hippo damage; MTL=hippo and perirhinal damage- bigger damage) - Arguing that the hippocampus was involved in low-level perception HOW: - given the perception task "which item is different?" in amnesics and had four conditions: color detection task, which object is different, which face doesn't belong, or spatial task (which room angle is different). No timer, just need to tell them which one is different. RESULTS: * HC & MTL patients were normal on color task* Hippocampal patients were impaired on scenes, but normal on objects and faces. --> hippocampus is important for scene perception *MTL patients were impaired on faces, objects & scenes IMPLICATIONS: --> Hippocampus is involved in perceiving complex spatial info --> Perirhinal cortex is involved in perceiving complex objects- Tells us that the hippocampus is actually a perception structure more than a memory structure --> expectation was that perception shouldn't be impaired if MTL is gone, as it relies on the cortex, but it was impaired.

Context cuing (spatial implicit memory) lesion study

Manns & Squire (2001) - context cueing in amnesia hypoxia [selective MTL region] vs encephalitis patients [bigger MTL regions] RESULTS: * hippocampal damage (hypoxics) does not disrupt context cueing (how long it took you to identify new vs old task)- faster for old items vs new items. * Extensive damage to MTL (encephalitis) disrupts context cuieng --> disruption in priming and they are showing no priming effect, not getting faster at identifying repeated items IMPLICATIONS: --> Parahippocampal gyrus (perirhial cortex?) is critical for learning of spatial configurations

Napping effects on implicit memory

Mednick et al., (2003) - visual texture learning after napping (10 hour delay) HOW: Test 1 (training)..... lear the visual search task then take a Nap (some had 0, 60, 90 min naps nad monitor how much sleep you got) .....10h delay.... Test 2- nap immediately after training and had different duration RESULTS: - people with no naps did worse- SWS sleep, but not much REM sleep, didn't how any difference, didn't show forgetting though, they stayed the same, it was stabilizing it * people who had SWS and REM showed memory enhancement didn't matter how long they slept --> 60 or 90 minute naps were sufficient to lead to memory enhancement effects (same size as whole-night effects) * Subjects who had both SWS and REM sleep did the best IMPLICATION: --> sleep benefits are rapid (e.g., 60-90 min) --> Both SWS & REM are important for implicit memory

Can Brain Stimulation Improve Memory?

Methods: 1) Deep brain stimulation (DBS)- electrodes implanted for clinical purposes in the brain or on the cortical surface 2) Transcranial Magnetic Stimulation (TMS)- high intensity magnetic fields on scalp used to induce electrical currents in cortex 3) Transcranial Direct Current Stimulation (tDCS) electrical currents applied directly to the scalp- induce DC current - stimulation may impact memory immediately by altering firing rates, or by altering neural plasticity

Memory Summary in HD and PD

NORMAL - explicit memory - perceptual implicit memory - conceptual implicit memory - STM IMPAIRED - skill learning - semantic memory (action and object naming)

Behavioral study on explicit and implicit memory on aging

Naveh-Benjamin (2000) - aging and explicit memory * Recall is more disrupted than recognition by aging * Associative/relational recognition is more disrupted than item recognition -- remember what was the font that was presented, what list it was on - big deficits seen in aging --> aging disrupts explicit memory Parker & Walker (1992) - effects of aging on recollection and familiarity (R/K/N recognition) --> aging selectively disrupts recollection - Healthy aging reduces recollection, but not familiarity-based recognition (remember/know, ROC, process-dissociation methods) - familiarity seems relatively stable across age while recollection declines

Age related memory impairments in Parkinson's/ Huntington's

Parkinson's/ Huntington's - basal ganglia - PRESERVED: STM, Recall, Recognition, Familiarity,, perceptual implicit, conceptual implicit, - IMPAIRED: skill learning, semantic (action-related)

Describe the differences in lesions and memory behaviors between Patient HM and Patient TJ. Where were the lesions and what deficits did they have?

Patient HM had a legion in the medial temporal lobe, while patient TJ had a lesion in the inferior/lateral temporal lobe. As HM had a damaged MTL, he had deficits in LTM but STM was intact but he could not encode new information. He still had limited knowledge of things that occurred in the past like the name of the high school he went to and his family home. Patient TJ on the other hand had a selective loss of old knowledge but could encode new information as his MTL was still intact.

In what ways do the memory deficits of AD and PD patients differ? In what ways are they similar?

People with Parkinson's disease will have skill leaning deficits, however people with AD can still perform tasks like the tower of Hanoi and not be impaired - people with AD cannot perform conceptual implicit memory tasks but people with Parkinson's are not impaired in this area (C.I is fine)

The word fragment completion task found that forgetting rates are slower for ________ than for _________

Perceptual implicit memory/Explicit recognition

Chronic Stress and Memory

Posttraumatic stress disorder (PTSD) - An anxiety disorder caused by an extreme stressor (i.e., intrusive memories, flashbacks, hypervigilance, sleep disruptions, avoidance of traumatic stimuli, numbing of emotions) Bremner, Randall et al., (1995) RESULTS: - PTSD in adults suffering childhood abuse- massive reductions in hippocampal volume and if they ran them on memory tests, they showed impairments. IMPLICATIONS: *long term stress can damage the hippocampus and impair memory

Human lesion studies on recollection vs familiarity - Neuroimaging studies

Ranganath et al., (1993) - Encoding activity related to predicting subsequent recollection and familiarity HOW: - Study: studied words in colored words/ fonts - Test: recognition confidence (familiarity) and word-color memory (recollection) (tell me what color the word was presented in). Make confidence judgments. - are there areas that activate when you are studying something that makes it familiar and vice versa RESULTS: •Familiarity confidence increased with perirhinal activity - more activation means more familiarity confidence •Recollection of color was related to greater hippocampal and parahippocampal cortex activation- if the hippocampus lights up when you are studying a word you will remember its color, and if it doesn't light up you are less likely to remember the color- parahippocampal cortex lights up for recollection too peririnal--> familiarity hippocampus --> recollection parahippocampal cortex --> recollection --------------------------------------------- Montaldi et al., (2006) recognition retrieval activity related to Remember (R) and Know (familiarity confidence F1, F2, F3) responses. - if scanned when retrieving information you see the same results as above RESULTS: • Hippocampus was related to recollection, but not familiarity • Perirhinal cortex was related to familiarity, but not recollection • note that parahippocampal cortex activity at retrieval is often related to Recollection --> when retrieving stuff and you are judging it as familiar you see changes in the perirhinal cortex

neuroimaging study that shows neural dissociation of implicit/explicit memory

Schacter, Buckner & Koutstal (1996) HOW: - Study: incidental encoding of words (study words and put you in a PET scanner and told to do some tasks) - Test: 'old' stem completion (should get priming), 'old' stem cued recall (explicit, given stems and told to remember what you studied to complete the word), 'new' stem completion (completing new words), in PET scanner RESULTS: * old stem completions were associated with less right occipital activation than new stem completions ---> neural priming- the cortex is involved with seeing the words when you studied them, so when you see the word again, it needs less blood and oxygen, so a deactivation. Priming the visual cortex, and so it does not need that much effort * old recall completions associated with greater medial temporal lobe activation than new stems --> explicit memory- hippocampus activates when you retrieve stuff ------ neural dissociation between explicit and implicit memory IMPLICATIONS: --> neural dissociation of implicit/explicit memory

Age related memory impairments in Semantic Dementia

Semantic Dementia: - PRESERVED: STM, recall - IMPAIRED: semantic

Which of the following is not a feature of implicit memory?

Sensitive to semantic manipulations

Skill learning and aging

Smith et al., (2004) - skill/procedural memory over long delays RESULTS: * young and elderly showed learning on procedural task, and both exhibited comparable savings over a 2.3 year delay. - make fewer errors after repetition, and older people who had learned the skill and tested them over 5 weeks and even after 2 years still remained the skill. IMPLICATIONS: --> normal skill/procedural memory in aging (note: few other comparable studies) - AGING DOESNT DISRUPT SKILL LEARNING

Boundary Cells

Solstad Boccara, Knopff, Moser & Moser, (2008) - Boundary Cells - no matter what environment it is placed in it will always for example like the left side. Responding to a boundary in a particular location in space. • Boundary cells response to borders or walls (e.g., the north wall in a square box that a rat is exploring) • Found in the entorhinal cortex (and the subiculum) • They are maintained when the environment changes shape (e.g., when a square stretches into a rectangle)- even from square to circle, it continues to fire. - in place cels, cells remapped when in a different location, but boundary cells are more general

Head Direction Cells/ time cells

Taube, Muller & Ranck (1990) • Head Direction Cells fire when the animal's head points in a specific direction • Found in the entorhinal cortex, subiculum, retrosplenial cortex... • Other cell types have been reported in the entorhinal cortex as well (e.g., 'speed cells').- faster the rat is moving, the more likely it is to respond ----------------------- Kraus et al., (2013) - 'time cells' respond to specific times, regardless of speed, while running on a treadmill- seen in CA1, CA3, and in entorhinal grid cells.

Memory Systems' Accounts of Amnesia

The MTL supports an explicit LTM, whereas the cortex supports implicit LTM and other cognitive abilities (STM, IQ etc.) - specialized memory system MTM system that supports explicit LTM - reliant on MTL - episodic 'explicit' LTM - BUT if MTL is removed: language, implicit memory, perception, and STM will still be intact as they are dependent on the cortex. PROBLEMS: - BUT: Conceptual implicit memory, contextual cuing and trace conditioning is reliant on MTL

Content specific recollection activity: 'cortical reinstatement effects'

The brain regions involved in encoding an episode are partially reactivated when that episode is later remembered - when retrieving visual information you reinstate the same visual regions that were involved in the initial percept. If audio, reengagement in areas that were involved in the audio encoding events. - hippocampus is linking the regions together and if you retrieve the memory you have some residual activation.

Define the memory systems account of amnesia, then describe one experiment and its results that pose a challenge to the memory systems account.

The memory systems account of amnesia states that there is a specialized memory system that supports explicit long-term memory. The MTL supports explicit LTM while the cortex supports implicit memory. We know that episodic explicit LTM is reliant on MTL, but if MTL is removed, we still have language ability, implicit memory, perception, and STM because it is reliant on the cortex. Conceptual implicit memory and contextual cueing and trace conditioning is reliant on MTL, so if legioned, people should have an impairment. One experiment that hindered this model is the finding that conceptual implicit memory is still partially reserved in amnesics. As a result, they can learn new information and even without a hippocampus. However, the model previously stated that it should not have a problem

Representational-Hierarchical Theory

The ventral stream (posterior visual cortex to perirhinal cortex) supports increasing complex feature conjunctions - early on in the visual system, we have low-level cells that respond to color or orientation (simple features in visual world) and they send information forward to other neurons that combine that information and the pass it forward again to become increasingly more abstract until you get to complex objects with multiple components and if this last portion was damaged, you get patients with semantic dementia. posterior (smile processing) --> anterior (complex processing) IMPLICATIONS: --> if you mess with the temporal anterior region, you will have semantic memory impairment. - Accounts for the finding that damage to anterior temporal lobe regions can disrupt high level semantic knowledge

Describe an example of a study that describes skill learning

Tower of Hanoi - the tower experiment, when they did it the second time they got faster, no explicit memory of doing it, but you remember doing the task

Conceptual Implicit Memory: damage to hippocampus (hypoxics) vs MTL (e.g., perirhinal cortex)

Wang et al., (2010) - Exemplar Generation Task HOW: - Study words: dresser, windsurfing, maple, .... - Test: long term delay and then asked to "name 4 examples of types of sports" - if you studied windsurfing, you were primed and thus give it as an example of a sport RESULTS: - people with no damage showed priming more often (named windsurfing as a sport), and if the person had selective hippocampal damage they were normal, if they had legions in the perirhinal cortex they did not show semantic priming. * Perirhinal damage (MTL) eliminates conceptual implicit memory, but hippocampal damage (H) has no effect * Perirhinal fMRI activation predicts conceptual implicit memory IMPLICATIONS: --> The perirhinal cortex is involved in conceptual implicit memory, and if damaged people can't learn new semantic information --> depends on which part of the MTL was removed- perennial damage means can't learn new stuff and can't remember semantic knowledge --> one form of implicit memory, conceptual is reliant on MTL, the perirhinal cortex, so it is needed for conceptual memory.

ROC affect and R and F (Yonelinas, 1994)

Yonelinas (2001) - Study: does deep (pleasantness) lead to better encoding then vs shallow (# syllables) encoding - Test: recognition confidence (ROC) RESULT:* Deep processing increase both Recollection and Familiarity, but R to a greater extent than F --> deep processing increases recollection a lot, and it also increases familiarity but not to greater extent IMPLICATION: --> R is more sensitive to elaboration/ semantics than is Familiarity, but not a complete dissociation --> Some manipulations can influence both processes

Lesion study explaining how semantic memory (knowledge) be acquired by amnesics?

argha-Khadem et al (1997) - how much knowledge can be learned without a hippomcpaus- three college aged students who suffered childhood hippocampal damage (e.g., during birth) caused by hypoxia (loss of oxygen) RESULT: * Severe memory impairments even after many years. --> no evidence of memory recovery (hippocampal function can't be taken over by other brain regions) * Graduated from high school --> no explicit memory of learning the stuff, but still learn and retain information IMPLICATIONS: --> Retained the ability to learn a great deal of semantic information about the world. - even without the hippocampus can learn conceptual knowledge, and motor learning however, it is unconscious as we don't remember learning it and can't retrieve it into conscious awareness, but you still learned it

what's the difference between conceptual and perceptual implicit memory (test q)

both are implicit, so measuring your memory without telling you to use explicitly use memory. The difference is that in the perceptual task I give you a perceptual retrieval cue (study words and at time of test given word fragment or flash it briefly on the screen as a retrieval cue). In the conceptual task, the cues are conceptual so the would say: give me examples of sports and you come up with something that you were primed with. So its conceptually related to the target

which of the following claims about brain training (eg. luminosity) apps is true?

brain training apps only help you learn the trained task

when comparing the color-location task, we learn that hippocampal damage disrupts visual STM in the ____ task, but not the ____ task

color wheel/ change detection

which of the following distinguishes healthy aging from Alzheimer's?

conceptual implicit memory

Post-encoding stress:

e.g., Andreano & Cahill (2006) - study a neutral story; cold pressor or warm water task; then 1 week delay; then free recall * stress right after encoding increased recall (especially larger effects in males) - the stressor enhanced memory ------------------------------------ Nielson & Arentsen (2012) - second last cognitive lecture of the year (day2) was followed by a 'live-action oral surgery' video (experimental) or neutral video *Stress led to a 10% increase in test scores for day 2 lectures! --> Stress increases memory for recently encoded info(cellular consolidation? or reduces interference? - after studied you had a stressful event that made you remember it less)

Sleep prior to and after learning (retroactive and proactive interreference)

e.g., Cellini, Torre, Stegagno & Sarlo (2016) - effects of a 90-120 minute nap before or after learning on explicit recognition memory for emotion and neutral images RESULTS: *A nap before or after learning improves memory * Effects were seen for emotional and neutral materials, and were related to total sleep time, not specifically to amount of REM or nonREM sleep. IMPLICATIONS: --> Sleep reduced proactive and retroactive interference - evidence for interference theory in explicit memory

Explicit Memory and sleep

e.g., Jenkins & Dallenbach (1924) - Recall was tested after periods filled with sleep or wake * sleep slowed forgetting- less forgetting after you learned something if you slept --> Interference - no new memories formed during sleep, thus reducing retroactive interference OR --> Systems Consolidation - memories maybe replayed and consolidated to the cortex during sleep (although it is very rapid (i.e., an hour))- usually think about SC as a slow process, but this occurs almost instantaneously

Stress during encoding:

e.g., Marloes et al., 2009 - encoding of pictures interleaved with stressful/neutral movies, 1 day delay, cued recall * stress during encoding increased recall But, others find stress during encoding decreases recall (for review see Shields et al., 2018). IMPLICATIONS: --> stress can either enhance or disrupt encoding (the critical factors are not yet known) --> a lot of individual difference Caveats with all stress effects: sex differences, emotion differences, inverted U-shape stress functions (can come into the experiment anywhere on the u-function).

Memory Cueing During Sleep

e.g., Rasch, Buchel, Gais & Born (2007) HOW: - learn card location associations during the presence of a context odor. In the background, there is an odor and after you learned the location associations, you go to sleep and track your sleep and wait until SWS and then reintroduce odor into the room and see that if in deep sleep, they want to see if they can remind you of the study phase. - Old or new odor presented during slow wave sleep- test memory for card location (then in the scanner) RESULT: *odor during SWS but not REM increased memory *odor in scanner while asleep led to hippo activation- lead the hippocampus to remember it studied something in the context- has to be introduced during SWS sleep otherwise doesn't show effect IMPLICATION: --> Rehearsal effect? consolidation? --> suggests we can learn things through using cues at the right time

Stress during retrieval:

e.g., Smeets (2011) HOW: - on day 1 study negative and neutral words; on day 2 in morning or afternoon put arm in ice vs warm water for 3 minutes; 30 min delay; free recall RESULTS: *Stress led to an increase in cortisol, cortisol was higher in morning * Stress led to a decrease in memory (negative and neutral words, morning and afternoon groups) - doesn't matter what time, there is a negative effect of stress IMPLICATIONS: --> Stress disrupts memory retrieval

What's a structural brain difference in the mechanisms that are used in explicit and implicit memory

explicit memory requires the medial temporal lobe, while implicit memory does not.

recollection likely relies on the ___, while familiarity relies on the ____

hippocampus/ perirhinal cortex

What happens if you legion to perirenal cortex in the BIC model

if you take out PR, you will take out what the objects are in the word so you can't identify what the objects are and lose the sense of familiarity.

Here's a list of words, read the words as quickly as you can - is this an explicit or implicit test

implicit test- didn't tell them to deliberately remember

fast forward to you age 73, which brain areas do you expect to be smaller than it is now?

lateral prefrontal

someone with a lesion where they have implicit memory impairment but won't mess up explicit memory

patient with right occipital lobe lesion would remove implicit memory, but then you would be blind. - Maybe it is not possible to selectively remove implicit memory because you would have to get through the visual cortex to get to the hippocampus, but one person showed this effect, patient MS.

What is one critical difference between Alzheimer's disease patients and people with amnesia?

people with AD have semantic memory impairments while people with amnesia do not 7) Semantic memory - Adlam et al., (2006) object naming and matching to function (A), recipient (B) or action (C), in AD and MCI (mild cognitive impairment - possibly pre-AD)- object naming is severely impaired and semantic knowledge * AD impaired on naming and all semantic matching tasks - wouldn't be able to name objects or identify that you can use a fork instead of a potato masher --> semantic memory is impaired in AD --> not just a language problem, they genuinely don't know how to name it or the semantic problem- one critical difference from amnesia

damage to the ____ eliminates conceptual implicit memory

perirhinal cortex

which of the following has NOT been shown to reduce the effects of aging?

pollution

Tulving & Schacter describe a nonconscious form of memory called _________ that is concerned with the perceptual identification of words and objects.

priming/ perceptual implicit memory

difference between recollection and recognition

recognition memory is a type of test: have you seen this before - recollection and familiar support recognition tests. Processes we use to test recognition --> recognition branches out into familiarity and recollection

aging reduces ___, but not ___

recollection/ familiarity

what brain change is thought to underlie the reduction in brain volume in healthy aging?

reduction in synaptic density

if stressed what brain area(s) will decrease

the hippocampus and anterior cingulate will decrease

how would a lesion like patient HM (i.e.. bilateral medial temporal lobe removal) affect somebody's episodic and semantic memory CHECK

they would be unable to form episodic memories, but would probably have limited procedural and semantic memory abilities

Maturation of newborn cells

• 1-6% cell turnover per month --> dentrate gyrus --> after 2.5 weeks it peaks and projects into the entorhinal cortex and Ca3 fields --> then after 2 weeks it is sensitive to new learning and synapses are sensitive and capture the information and sends it to --> after 2 months is the same as other adult cells. - primed for learning new information after - if the neurons aren't engaged in the memory circuit they will die. • Neurogenesis is increased by exercise, antidepressants like Prozac, ECT, and Estrogen. - good for memory and thus increases neurogenesis • Selective effects of stress and antidepressants on neurogenesis in DG

Semantic Dementia (SD)

• Deterioration of anterior temporal cortex (generally greater on left) • Deterioration of semantic knowledge (e.g., deficits on word and picture naming, sound-object matching, picture naming, etc) with relatively preserved explicit memory- hippocampus is not disrupted, but surrounding cortex is. ---------------------------------------- Hodges & Patterson 2007- pyramids and palm trees task- what objects go with which sound- shown pyramid and have to choose palm tree as it goes with it (testing semantic memory). Then in the end, you are presented with a surprise episodic memory task for the material you just studied. Asked which image was in the study phase (tested episodic memory) RESULTS: •Semantic dementia patients were impaired at semantic decisions but normal on episodic memory- knock out knowledge of the object but doesn't hurt episodic memory IMPLICATIONS: --> dissociation of semantic memory from episodic memory- knocks out knowledge of what the object is and it doesn't impair your episodic memory for the object --> you could ask them what the object is, able to identify what the objects they studied were, but don't know what it is. Suggesting that semantic memory is dissociable. * double dissociation from what we see with hippocampal patients as hippocampal patients would do fine on the semantic memory task and show episodic memory impairments ---------------------------------------- IMAGING STUDY Rogers et al., (06) - regions of atrophy in Semantic Dementia patients (left temporal lobe) - asked them to make semantic judgments either specific or general. Tell me if image is an animal or vehicle (general), or intermediate questions (is it a bird or a dog?) or ask (specific)- kingfisher vs robin. RESULT: * impaired at 'Specific' discriminations - the more specific the more impaired * PET activity in normal controls (same left lateral temporal lobe region was more active for specific level semantic judgments than general level judgments) IMPLICATIONS: --> High level semantic representations in the ATL (anterior temporal lobe)

Neurogenesis and Stress

• Neurogenesis is decreased by stress, depression, and normal aging- few cells will survive - Chronic stress reduces DG neurogenesis, but these deficits appear to recover. --> after 3 weeks of living under a cat, the rats show increased recovery of neurogenesis • Selective effects of stress and antidepressants on neurogenesis in DG --> affects the number of neurons that survive --> giving normal rats antidepressant drugs increase their neurogenesis, but the same effects not found in humans.

Sparce activity in the hippocampus

•Activity patterns of neurons in the hippocampus (CA3, CA1) and cortical input areas (entorhinal cortex and subiculum), for a rat running on an 8 arm radial maze, with the bars along each arm indicating how much the neuron fired for each direction of motion along the arm. •Hippocampal neurons (CA1 and CA3) are less responsive and more selective to specific locations and directions than cortical neurons • DG is particularly sparce --> Ideally suited to represent individual episodes - CA3 and CA1 are sparse so when the rat is running it experienced something it is coming to represent that memory. CA3 and CA1 are like place cells, light up in very specific situations, and are limited to specific locations.