Cog Neuro Exam #3

permanent stores of knowledge

single

• Declarative (Explicit)
• Nondeclarative (implicit)

• Facts (Semantic)
• Events (Episodic)

• 1. Skills and habits
• 2. Priming
• 3. Simple classical conditioning
• 4. Nonassociative learning

• LTM knowledge that can be retrieved and then reflected on consciously (conscious access required to engage)
• Ex: Remembering your elementary school

• Knowledge that can influence thought and behavior without any necessary involvement of conscious awareness
• Ex: Dialing a number when you see the phone but being unable to say the number from memory

• Memory for specific episodes in our lives occuring at particular places/times (what you had for lunch)
• autobiographical
• EVENTS

like a mental dictionary it contains knowledge about words, symbols, general knowledge about the world and memory for other facts

FACTS

• -motor skills
• -perceptual learning
• -grammar acquisition
• -classical conditioning

you are able to recognize something on the first exposure, on the second exposure you require less perceptual information to determine the image

• implicit (procedural)
• explicit (semantic)
• explicit (episodic)

Getting info into the system (earning, studying)

Getting info out of the system (accessing, remembering)

Holding info in LTM

Encoding -> Storage -> Retrieval

• Repetition (spaced vs. massed)
• Encoding variability
• Generation
• Rehearsal
• Levels of Processing (transfer appropriate processing, encoding specificity principle)

Zechmeister showed that from a Word List Recall, words studied twice had better recall performance when studied distributed over time (Spaced) vs. crammed into consecutively (massed)

No- penny example

• Dog-Lion Paired Associates test
• Variability group had the words Dog-Lion and the pictures of a dog and lion alternated.
• Condition group had only the words dog-lion repeatedly
• The variability group had better recall over the amount of trial

• 4-digit number memory task (Glenberg et al):
• 1. study 4-digit number for 2 seconds
• 2. repeat word aloud for 2, 6, or 18 seconds
• 3. recall 4-digit number
• 4. surprise memory task-recall repeated word

• Results: no signficiant difference for word recall based on rehearsal time (2, 6, or 18)
• Conclusion: Mere rehearsal is not effective for long-term storage of information

• Maintenance Rehearsal
• Elaborative Rehearsal

• Repetetive recycling without further thought/processing (like Glenburg et al. study)
• -Not very effective for LTM encoding

(how much you repeat a word has no effect on whether you remember it)

• Rehearsal that emphasizes encoding of meaning
• Is effective for LTM encoding

Elaborative

Probability of recognition as a function of typeo of elaboration (semantic or rhyme) and whether it was generated or read)

best recognition for words that were generated rather than read, and for pairs with semantic meaning (synonym) than for words that rhymed

the more elaborated your processing, the more preserved the trace is

a differnt level of processing- just rote or sound has worse memory bc you don't have to relate to it, it is a more shallow level of processing

• Memory is determined by how the person processes it, not by how long the information stays in the system.
• Therefore:
• Deep processing leads to strong LTM traces
• Shallow processing leads to poor LTM traces

rehearsal is relatively unimportant, type of processing is more important

• 3 types of processing respond Y/N
• Structure (is word in caps)
• Phonological (does word rhyme)
• Semantic (does word fill in the sentence blank)

• Response Time:
• Shortest for structure, then phonological, longest for semantic (suggesting that deepest processing is for semantic)
• Recognition of Words:
• least remembered for structure, same order (suggests that memory is best for items processed deeper)

• Two groups: intentional (knew taking part in free recall experiment)
• Incidental: did not know

• people are told to orient to different attributes of the words.
• As type of processing gets deeper, recall gets better, but even when not told to remember later on, the word recall is comparable to that when people are told to orient to the pleasantness of the word
• shows that the intention to learn does not influence recall performance!

• major seizure -age 16
• bilateral medial-temporal lobe resection (hippocampus and nearby structures)
• discovery of anterograde amnesia

• Average IQ
• normal perception, well-mannered
• normal language comprehension-understands jokes
• can engage in sophisticated conversation
• as soon as you leave the room- he forgets all about you and the conversation

McDonalds drivethrough and repeatedly telling him about knowing a guy name John McDonald and telling the story

Elvis Presely and Kennedy conversation

Some brain injury has rendered the patient incapable of retaining new experiences, but leaves other cognitive functions relatively intact

• Amnesia from brain injury,
• his nondeclarative memory is in tact, but declarative is not.
• He is unable to create new memories

• Entorhinal Cortex
• Perirhinal Cortex
• Parahippocampal Cortex

• part of the hippocampus in tact but all the tissue input was severed during surgery.
• bilateral damage to medial-temporal lobe structures:
• Entorhinal cortex removed entirely
• Perirhinal cortex and hippocampus extensive damage

• the memory trace
• may be in the medial temporal lobe
• hippocampus

PPA- parahippocampal place area

are interconnected with most of the rest of the brain

• Loss of CA1 field of hippocampus (type of cells) after ischemic episode
• Damage localized to CA1 subregion of hippocampus
• loss of spatial configuration

lack of oxygen causes damage

(Stroke) damage to tissue from blood

• 4 Main Divisions based on cytoarchitechtonics (cell structure)
• 1. S
• 2. CA1
• 3. CA3
• 4. DG
• These feed into the 3 main cortices
• entorhinal
• perhirhinal
• parahippocampal

• 6 mos after amnesia onest cannot copy from memory 10-20 mins later
• 23 mos after amnesia onset copy is a little better

• hippocampus ->
• mamillary bodies (projects via fornix) ->
• thalamas->
• cortex->
• hippocampus

results in anterograde amnesia

Radar tech for air force- fencing foil went up right nostril

Thalamus and mammilary bodies, hippocampus OK

• severe amnesia- inability to encode new memories
• forgets the events on TV when commercial comes on
• lives as he did in the 50s

Working memory is in tact, but when he disengages (commercial), he forgets (no long term memory to store)

• Damage to mammilary bodies
• thalamus
• medial/inferior frontal lobes

• infabulation (lying), memory damage, inhibition damage.
• often make thinigs up

• Retrograde
• Anterograde

• 1. Older memories are better remembered (Ribot's Law)
• 2. Retrograde amnesia tends to shrink over time (lost memory may be recovered over time)

• distant past---recent past----new information
• some memory -retrograde ------anterograde

memories before the brain damage in the distant past are slowly recovered, the distant past is remembered first (this is the slide with the three arrows)

• DC bus driver moved to boston to work in drugstore, then mattress factory
• had temporal lobe hematoma resulting in amnesia
• 1 mo. later: says he lives in DC
• 4 mos later: says he lives in boston, works in a drugstore
• later: knows he works in mattress factory
• discharge: remembers 24 hours before accident

no

• Memory loss
• retrograde amnesia for roughly 6 mos prior to ECT treatment
• anterograde amnesia for roughly 2 mos post ECT treatment
• memory eventually returns to normal

some disruption with retrograde amnesia they they recover from, so transient though that cannot figure out the specific nature of the deficit

• Formation of long term memories of engrams
• A memory for a visual event has a visual pathway

• Experience of the event- sum total of what the event was (visual aspects, memory, all parts)
• Interconnectedness of the medial temporal lobe structures
• set of regions is integrated as a composite of the event

• Visual pathway --> perception of event
• Elaborated processing--> where/what pathways
• Further elaborating--> this is nice, i remember when...
• Back to hippocampus- and all nodes to hippocampus activated,
• Consolidation--> all composites connected to hippocampus
• when you have a memory cue- that thought is connected to the hippocampus, and hippocampus connected to everthing else so you re-experience

representation within visual and other association areas

• One node can activate entire memory without hippocampal involvement
• if the memory is already formed, does not require hippocampal activation

• retrograde without anterograde amnesia
• -this has never been observed after brain injury
• "fugue states" are different- may relate to psychological trauma

LTM- mostly episodic

implicit does not require conscious access

• trace image in mirror and rate and errors are tracked
• teh # of errors decreases with numerous trials
• day 2- start rusty but overall better (once learned it is maintained)
• HM starts rusty but ends up where he left off day 1 because this doesnt require conscious access

• Sequence of flashes feel random but are actually a sequence
• person improves on the task over time but doesn't realize they are improving
• again shows an implicit process

• Mirror Tracing Task
• Serial Reaction Time Task

Yes they are, Motor skill learning is ok- we know from Mirror tracing and spatial reaction time tasks

• people show improvement even after 90 days
• normal controls don't differ on this task from korsakoff and amnesic pts (everyone improves)

• At the end of Day 2, amnesic group is comparable to the control group.
• They may not remember the explicit rule, but get back into task through implicit processing
• Controls explicitly learn the rule and can benefit from it

• Basal Ganglia
• Medial Temporal Lobe

• Caudate, putamen, globus pallidus
• habit/skill learning
• damaged in huntington's, impaired in parkinsons

• Hippocampus, entorhinal, perhirinal cortex)
• Declarative Memory

• UCS: smell of food
• UCR: salivation
• CS: sound of bell
• CR: salivation

• UCS: air puff
• UCR: eyeblink
• CS: light/tone
• CR: eyeblink

so- can learn the association and retain it for at least one day- but have no memory for the procedure they learned just 10 minutes later

• parts of a picture until the whole picture is represented-
• you learn images and can ID it if you have seen it before
• HM does better on this task with repetition.

• give list of words
• give word fragment and ask to complete word
• performance is better when asked to complete words in the list vs. new words

• Given a list of words and asked how much do you like each of them
• Then free recall of words, cued recall (word completion with a list word), and completion (with any word)
• Results: Amnesic have impaired declarative (free recall and word recognition), but priming is preserved as seen by performance on the stem completion task being no different than the recognition)

• MS - declarative normal, perceptual priming impaired
• HM- declarative impaired, perceptual priming normal

know info but cant remember when you learned it

• HM Hippocampus medial and temporal lobes
• Anterograde facts ??
• Anterograde episodes X
• Retrograde facts OK
• Retrograde episodes ??

• Motorcycle accident
• Damage to medial and temporal lobe
• both anterograde and retrograde amnesia for episodic info
• memory for facts is intact, and can learn new facts
• What KC knows about his past is functionally the same category as his knowledge about other people's past (photograph of him with curly hair)

unclear (perceptual cues with words)

• KC Hippocampus
• Anterograde facts ??
• Anterograde episodes X
• Retrograde facts OK
• Retrograde episodes X

• suffered hippocampal damage (perihrhinal and parahippocampal cortex intact)
• Severe amnesia

Ok performance on the immediate recall and very poor performance on the delayed recall

Copy is normal, delayed recall is very poor

• Beth Jon Kate
• Hippocampus damage
• Anterograde facts OK
• Anterograde episodes X
• Retrograde facts NA
• Retrograde episodes NA

Episodic is more strongly impacted than semantic memories, although sometimes semantic is impaired, but usally ok

Yes- Semantic Dementia

• Damage is in the anterior/lateral temporal lobes
• usually caused by progressive, degenerative disease (like Pick's)
• Results in severe retrograde amnesia for semantic (not episodic) information

ask what a violin is have no idea, but can describe teh important events in the their lives and speech is not repetetive

• Alzheimers- hippocampal atrophy
• SD- left lateral temporal lobe atrophy

• SD
• Lateral temporal Cortex damage
• Anterograde facts X
• Anterograde episodes OK
• Retrograde facts X
• Retrograde episodes OK