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Flashcards in Exam 3 Deck (73):
1

Sensory Memory

milliseconds to seconds

Iconic memory, echoic memory

2

Short-Term Memory/Working Memory

seconds to minutes
REHERSAL

3

Long-Term Memory

days to years

not really about a passage of time: when falls below level of consciousness
RETRIEVAL

4

Global Amnesia

profound forgetfulness

Regardless of modality of information (names, faces, places, odors and music all forgotten)

Regardless of how information is presented (visual, auditory, olfactory)

Amnesiac syndrome: impaired declarative but spared nondeclarative

amnedia tends to spare nondeclarative memory

5

Retrograde Amnesia

inability to remember prior memories

6

Anterograde Amnesia

inability to form new memories

7

Patient H.M.

severe epilepsy; seizures starting at age 15
bilateral removal of MTLs (hippocampus, but posterior hippocampus still present)
William Scoville

Anterograde amnesia – since lesion
Suggests encoding deficit

Retrograde amnesia – prior to lesion
Suggests consolidation deficit

temporally graded retrograde amnesia
Memory consolidation takes time
This is because the neural pathways of newer memories are not as strong as older ones that have been strengthened by years of retrieval and CONSOLIDATION

8

Episodic Memory

Events (declarative/explicit)

9

Semantic Memory

Facts (declarative/explicit)

10

Procedural Memory

Skills (non-declarative/implicit)

11

Medial Temporal Lobe

Monkeys!!!

12

Hebbian Learning

“When an Axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A’s efficiency, as one of the cells firing B, is increased”

- found in hippocampus

-the cellular basis of learning involves strengthening of a synapse that is repeatedly active when the post synaptic neuron fires

- repeated activation causes A’s efficiency, as one of the cells firing B, to increase

-synapses that are active at the same time that the post synaptic neuron fires are strengthened over time

13

Mechanisms of LTM

Long-term potentiation (LTP)
Hippocampus
NMDA/ AMPA receptors

14

LTP

long-term potentiation

(LTP) is a persistent strengthening of synapses based on recent patterns of activation

long-term increase in excitability of a neuron to a particular synaptic input caused by repeated high-frequency stimulation to that input

1. Repeatedly stimulate a single pathway in hippocampus slices.
2.Afterwards, new stimulation caused greater excitatory post-synaptic potential
3. This is long-lasting...And Hebb was right!
4. It works because of NMDA receptors!

15

Hippocampus

Hebbian learning/LTP occurs here

16

Iconic v. Echoic Memory

Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over.

Overall, echoic memories are stored for slightly longer period

While seeing something or touching something is a repeatable and reoccuring event (speaking in terms of short intervals), hearing is a single occuring event. It was probably an evolutionary benefit to keep and process the auditory input better.

last longer than iconic memory because what you have in the basilar membrane vibrating in your cochlea. As a result, it continues to have some kind of sensation and causes action potentials

17

Types of Memory

Sensory Memory (mil-sec)
Short-Term/W Memory (sec-min)
Long-Term Memory (days-yrs)

Types of Long-Term Memory
Declarative (explicit m)
Non-declarative (implicit m)

Declarative (explicit)
Semantic (facts)
Episodic (events)

Non-Declarative (implicit)
Procedural (motor skills, ex: riding bike)
Perceptual
Classical Conditioning
Nonassociative Learning (habituation sensitization

18

Perceptual Memory

Perceptual memory, that is the ability to interpret
incoming stimuli by recognizing individuals, by
categorizing them, and by noting relationships
between such individuals and categories, is ubiquitous
among animal species, as is the learning of these
facilities

Animals of all sorts can identify food sources, potential
mates, potential predators, etc. Pigeons have been taught to

categorize using such concepts as tree, fish, and human,
some well outside of their evolutionary background
(Herrnstein 1984). Honey bees have been taught to identify
human letters independently of size, color, position or font

19

Findings of Brenda Miller

IQ better than pre-op (112)
Fewer seizures

20

Memory System

See paper

21

Amnesia Timeline

See paper

22

H.M. Memory Timeline

See paper

23

H.M Types of Memory Deficits

DECLARATIVE: lost and impaired
EPISODIC: complete loss (couldn't remember new people/events)
SEMANTIC: impaired, but some left in tact (rock'n'roll)
NONDECLARATIVE: spared
WORKING: intact
- normal digit span (could count, remember #s, but constant rehersal needed otherwise forgotten upon interruption)
PROCEDURAL MEMORY: intact
- mirror tracing, pursuit rotor tracing, Implicitly familiar w testing equipment, ant amnesiacs can still learn piano pieces
- HM could do priming conceptual task (fish card fill-in)
- Tower of Hanoi (improved, procedural learning, does not remember doing so though)

24

Temporally Graded Retrograde Amnesia

Memory consolidation takes time!

Occurs because the neural pathways of newer memories are not as strong as older ones that have been strengthened by years of retrieval and CONSOLIDATION

hippocampal memory trace
but cortical reinstatement

25

Memory in the Brain

Hippocampal activation greater during successful remembering (compared to unsuccessful attempts to remember)

Cortical activity patterns are reinstated in appropriate parts of cortex

26

Bliss & Lomo

stimulate CA3 --> output measured in CA1

1. Repeatedly stimulate a single pathway in hippocampus slices.
2.Afterwards, new stimulation caused greater excitatory post-synaptic potential
3. This is long-lasting...And Hebb was right!
4. It works because of NMDA receptors!

27

NMDA's role

- LTP is dependent on NMDA receptors
- Mg=agonist that has block on NMDA receptor
- Opens upon high-frequency stimulation , allowing Ca to flow in; activation of NMDA receptors triggers LTP

28

Agonist/Antagonist

agonist: molecule that occupies receptor and activates

antagonist: molecule that occupies receptor and blocks
- Mg, AP5

29

NMDA and AMPA

- Both glutamate receptors
- Binding by glutamate should open channel, but not when Mg in place
- Receptor opens upon high-fq stimulation (Mg block removed, allowing Ca to flow in)
- Ca influx generates series of intracellular chemical cascades
- when these cascades reach the post-synaptic terminal, this activity results in LTP

30

Morris Water Maze

goal: assess importance of NMDA receptor in learning

circular opaque pool
water-averse rat
platform hidden

NMDA antagonist: AP5 -- administered to select rats

control + AP5 rats--> thrown in water to learn platform location

when platform taken away...
CONTROL: biased to platform quadrant
AP5 rats: random swimming

--> NMDA RECEPTOR ANTAGONIST BLOCKS SPATIAL LTM

-------------------------
administer AP5 after learning..no effect

AP5 critical during learning, not important for RETRIEVAL; once a memory has been formed/LTP has occured, NMDA receptor no longer needed

31

AP5

NMDA antagonist

blocks LTP by binding to NMDA receptor but DOES NOT interfere with regulatory synaptic transmission

NMDA RECEPTOR ANTAGONIST BLOCKS SPATIAL LTM

32

Complementary Learning Systems Model

Mclelland & O'Reilly

LTP consists of two forms of memory:
specific episodes (episodic)
generalized patterns (semantic)

Pattern separation (formation of distinct episodic memories) is FUNDAMENTALLY INCOMPATIBLE with pattern completion (abstraction of specific episodes to inform general principles)

Rapid retention of arbitrary associations /= cannot be supported by the same system that encodes for generalized principles (a necessarily slow process)

----> SUGGESTS THAT...
The hippocampus rapidly learns episodic memory...
the way a mem is reinstated
[IN FULL DETAIL] [IN GENERAL PRINCIPLE]
determines whether it will be transferred to the cortex as an episodic or semantic memory

33

Pattern Completion v. Pattern Separation

Pattern Separation: Formation of distinct episodic memories; Rapid retention of arbitrary associations

Pattern Completion: The abstraction across specific episodes to distill and/ or update general principles; Slow process of abstracting generalized principles

34

Systems Model, evidence for...

1. Hippocampal activation greater during successful remembering (compared to unsuccessful attempts to remember)

2. Cortical activity patterns are reinstated in appropriate parts of cortex

35

Components of Systems Model

1. Encoding: hippocampal activity should be greater during successful encoding compared to unsuccessful encoding

2. Retrieval: hippocampal ‘memory’ should be reactivated during successful remembering

3. Retrieval: cortical activity is reinstated in appropriate regions of cortex (depending on what you can recall.)

36

Systems Model: Hypothesis 1

Encoding: hippocampal activity should be greater during successful encoding compared to unsuccessful encoding

37

Systems Model: Hypothesis 2

Hippocampal Retrieval: hippocampal ‘memory’ should be reactivated during successful remembering

38

Systems Model: Hypothesis 3

Coritcal Retrieval: cortical activity is reinstated in appropriate regions of cortex (depending on what you can recall.)

39

Consolidation

stabilization of a memory trace after its initial acquisition

process in which hippocampus-dependent memories become independent of the hippocampus over a period of weeks to years

40

Pattern Completion

Partial input serves as memory cue, reinstating hippocampal network pattern of activity, this is known as pattern completion.

41

Systems Model Process

1. Experience leads to a cascade of brain activity (visual, spatial, auditory, etc.).

2. This distributed, parallel processing of brain activity is inputting into the hippocampus.

3. The hippocampus turns this input into its own pattern of activity, generating a network ensemble.

4. The more strongly this network becomes interconnected, the more likely you are to remember that experience (dependent on LTP and replay during sleep and rest).

(Retrieval)

5. Partial input serves as memory cue, reinstating hippocampal network pattern of activity, this is known as pattern completion.

6. If hippocampal ensemble does pattern complete, this leads to cortical reinstatement. Cortical reinstatement/reactivation is what gives rise to conscious experience of remembering.

1. Hippocampal Activity --> 2. Hippocampal Reinstatement --> 3. Cortical Reinstatement

42

Subsequent Memory Paradigm

Assessing whether hippocampal activity during encoding be predict subsequent memory

measures: imaging data, recall ability

1. Look at list of words, record BOLD responses.
2. Memory test (equal # of new, old words).

Words with greater brain activity should be remembered better. Imaging data should correlate with % correct words.

Significantly greater activity for words remembered than forgotten.

43

Indexing item and source memory
subsequent memory task

(1) Imagine a scene (2) read word backwards

Testing for: Object and Context

Perirhinal Cortex activity: greater activation for remembered objects

Hippocampus: greater activation when both remembered

SUGGESTS THAT...
Hippocampus is important for encoding patterns/associations

44

Simpsons Experiment

Neuron reactivated right before recall

Same neurons during experience are again activated during retrieval

reinstatement within the same neuron; N 46 in hippocampus

45

Memory Retrieval

Auditory pairing, visual pairing
Cat-meow, Cat-pic

Auditory reinstatement even without auditory stimulus

SELECTIVE REINSTATEMENT
CONTENT-DEPENDENT

Cortical activity is reinstated in appropriate regions of cortex (depending on what you can recall)

46

Memory Reactivation

paired associates
scene, face, object

computational classifier: train pattern classifier to predict visual category from brain activity

no pic, just looking at cue (Oprah pic)

FLAG --> I remember scene, face, or object

47

Sleep and Rest

The more strongly this network becomes interconnected, the more likely you are to remember that experience (dependent on LTP and replay during sleep and rest).

48

Tambini & Davachi (2013) study

Memory consolidation is thought to depend on the reactivation of patterns of brain activity that characterize recent experience

patterns of hippocampal connectivity that characterize an encoding experience persist into immediate rest periods. Furthermore, this persistence is related to memory for the preceding representations, suggesting that postencoding measures of persistent activity patterns may contribute to memory consolidation

-------


what does hippocampus activity look like

is evidence that pattern of activity persists into replays during rest; patterns of hippocampal activity most similar during immediate rest period

experience-dependent changes in brain function

49

Cued Memory Activation

Information acquired during waking can be reactivated during sleep, promoting memory stabilization.

performance was more accurate for the cued compared to the uncued sequence

50

Place Cell

A place cell is a type of pyramidal neuron within the hippocampus that becomes active when an animal enters a particular place

51

Fragments Task

Warrington & Weiskrantz

performance on two memory tests administered 10 minutes after the presentation of 16 words.

Amnesic patients performed as well as control subjects on what the authors termed a “cued recall” task, in which the first three letters of a studied word (so-called “word stems”) were presented and the subject was “required to identify the stimulus word”

The patients were markedly impaired, however, on a test of Yes/ No recognition.

amnesia was better characterized by “altered control of information in storage” (p. 419), rather than a consolidation block. That is, they argued that new information “gets in there” but that the amnesic syndrome makes it more difficult to access this information.

52

Priming

Facilitative changes in the ability to identify, generate, or process an item due to a specific encounter with the item

priming may reveal the workings of implicit memory

53

Repetition Suppression

A reduction of neural response that is often observed when stimuli are presented more than once, compared to novel stimulus

repetition priming --> repetition suppression

54

Repetition Priming

facilitative processing
rt speed up

55

Visual Word-Form Priming

same font-different font
no change in priming RT in MS

suggesting that MS brain lacks perceptual sensitivity
visual cortex damage ; R

__
R (visual-specificity hem)

R hemisphere processing is more visual-spatial
L hemisphere processing is more perceptual verbal
Priming dependent on font in R hemisphere
Same font better recall

--
different forms of priming
perceptual and conceptual priming

56

Valence vs Arousal

Avoidance (negative) vs Approach (positive)

57

Universal Emotions, 6 emotions

(Ekman)
happiness
fear
anger
disgust
sadness
surprise

58

Dimensions of Emotion

Valence
Avoidance (negative) vs Approach (positive)
guilt . want

Arousal
intensity

59

Measures of emotions

Direct
self-report manipulation
expresssion facial expression

Indirect
Galvanic skin response - GSR or SCR
Emotional stroop task
Pupil dilation

60

Schachter experiment

attribution of emotion
Emotion = arousal + attribution

interpretation/attribution to stimulus
emotion = construction

when an emotion is felt, a physiological arousal occurs and the person uses the immediate environment to search for emotional cues to label the physiological arousal

---------
Injected with epineprine or placebo

participants who had no explanation of why their body felt as it did, were more susceptible to the confederate.

61

Dutton & Aron shaky bridge experiment

misattribution of emotion

natural setting that would induce physiological arousal

because they had transferred (misattributed) their arousal from fear or anxiety on the suspension bridge to higher levels of sexual feeling towards the female experimenter

62

Facial Feedback Theory

facial movement can influence emotional experience

ex: an individual who is forced to smile during a social event will actually come to find the event more of an enjoyable experience


Stunted feedback: Botox vs Restylane
Botox: kills nerve - and feedback
Restylane: just a filler - leaves feedback intact)

Botox injected participants report less emotion in response to pleasant and unpleasant films after procedure

63

Orbitofrontal cortex

behavioral deficit
explicit knowledge of appropriate behavior is intact

64

Phineas Gage

emotional, frequent outbursts of anger, rage, couldn’t inhibit inappropriate behavior
1843‘Gage was no longer Gage’

damage to orbitofrontal cortex

knowing v. doing

65

Utilization behavior

utilization behavior: use a stimulus in sight even when inappropriate

automatic reaction to stimuli

syringe - diabetic

contextually inappropriate behavior

ask v. knowing

66

Emotional Detachment

Pts can describe their actions but show EMOTIONAL DETACHMENT from consequences

OVERPRAISING
not sensitive to contexual feedback

Knowing vs Doing - behavior is off but patients still ‘know’ what is appropriate

(e.g. over-praising task and generating nicknames task)

watch video and know it's weird

67

Amygdala

Lesioned responses
Emotional memory

sumbliminal matches

68

Agnes

no outward signs of emotion
no facial expression
no feelings toward other people
felt empty, zombie-like

Other patients lose prosody = emotional component of speech

damage to OFC

69

Agnes

no outward signs of emotion
no facial expression
no feelings toward other people
felt empty, zombie-like

Other patients lose prosody = emotional component of speech

damage to OFC

70

SCR: OFC v. Control

SCR: skin conductance response; measures sweat gland activity; indicator of arousal

NEUTRAL/FLAT IN OFC PATIENTS

71

Conditioned-fear respose

skin response to emotionally scary stimulus

72

Conditioned Fear Response

(classical conditioning)

shock (US)
rat shows fear/startle response (UR)
pair shock (US)+light (CS), rat learns association,
light alone (CS) elicits fear/startle (CR)

Amygdala lesions impair fear conditioning in animals and humans

73

Fear memory

physiological response

vs. declarative memory - what is going to happen