L+M Exam 4

organic amnesia types

retrograde, anterograde, transient global amnesia, loss of specific knowledge or skills

causes of amnesia

organic (brain damage)

psychological

ex= infection such as encephalitis, Korsakoff’s syndrome, stroke, etc….

retrograde amnesia

loss of memories prior to an incident

-disruption of memory consolidation systems such as LTP

causes = severe blow to the head or stroke

can be induced via electroconvulsive therapy (ECT) which is the treatment for depression

(now days if you put two electrodes on one side of the head less memories are list)

can also be induced via electroconvulsive shock (ECS) but this is used ONLY on animals OKAY

anterograde amnesia

loss of ability to create new memories after an incident

-may improve wen dominant amnesia is retrograde HOWEVER if anterograde is dominant it is permanent t

causes = damage to medial temporal lobes and hippo and diencephalon

-most people don’t even know they have amnesia

-diencephalic damage (most common) = damage tot thalamus, hypothalamus, mammillary bodies or Korsakoff’s syndrome (usually leads to loss of control of thought)

-no von resttorff effect, trouble imagining the future, no boundary extension effect

-STM in tact they just have faster forgettign

-they lose sense of personality

-new procedural memories can be made (mirror tracing with HM), recollection impacted more than feelings of familiarity

-you MAY say you remember something but its just familiarity

-non declarative memories in tact so its priming

-difficulty making decisions and difficulty knnowning how past events unfolded

Ribot’s Gradient

recent memories lost (bc they haven’t been fully consolidated yet)

older memories retained

-memory recovery over time

-loss of event but NOT OF SEMANTIC KNOWLEDGE

-older memories will come back first when you start to remember then newer mems

areas that show more gradient vs areas that don’t

-areas associated with declarative memories show more ribot gradient such as the frontal and temporal lobes

-areas such as striatum, bilateral, and midbrain show less gradients

PS case study

believed himself to be a WWII navy man still

everything for him was stuck in the 1940s

Ben Franklin Amnesia story

was elctrocuetd lol

and said it felt good

HM case study

entire hippo taken out

loss of declarative memories encoding and storage

all started because of his epilepsy

still had good short term memory and showed some evidence of implicit memory

one hack to improve anterograde amnesia

a period of wakeful rest

Clive Wearing Case study

anterograde amnesia

retained ability to play and conduct music

AB case study

poor memory for words/sentetnnces but good memory for complex stories

forgetting for surface level, retention for situational modelT

TR case study

remembered WHAT and WHERE

but not WHO and WHEN

examples of people living with anterograde amnesia

Sheila Moakes (teacher)

JC (law student)

Mr. S

-all feel like they are constantly “coming out of it”

-much easier if you have a good support system

amnesia is usually a mix

a both types

transien global amnesia (TGA)

a brief amnesia period

typically last 3-8 hours and are therefore difficult to study

usually though 4 hours or less

underreported

mem loss is between a few hours two several decades however losss of a few months is most common

-people often in confused state and repeatedly ask the same questions

-typically occurs in people age 50-70

-oftten preceded by stressful activity (physical or emotional) (more common during colder months)

may be caused by a disruption in blood flow

semantic amnesiia

deficit in the ability to retrieve semantic knowledge

damage to the temporal lobes (speficially anterolateral portions, more likely with left hemisphere damage)

rare in the absence of a neurological syndrome (ie Alzheimers )

can be very specific (ie can identify famous people but not landmarks)

dimensions example (visual motion vs frequency)

anomia

issue with LTM

inability ot retreiver word meanings

WORD FINDING BASED

apraxia

inability to correctly use objects

SEMANTIC MEMORY ISSUE

know what objects are, just can not use

Aphasia

inability to use language

LTM issue

Broca’s = difficulty producing (but not comphrending)

Wernicke’s = difficulty comprehending language

Amusia

LTM issue

inability to comprehend or produce music

-you can still hear sounds just can’t perceive or produce music

Prosopagnosia

LTM issue

inability to identify faces

(unable too integrate faces into a whole)

STM Amnesia

amnesia may affect short-term, but not long term

examples = primacy effect but not recency effect, or difficulty remembering spoken words but normal for visual words

caused by damage to the parietal lobes (WM), near the frontal lobes (verbal info)

-damage to the parietal lobes, near the occipital lobes

psychogenic amnesia

amnesia for life events or personal knowledge

-unrelated to clear physiological or neurological changes

malinngerinign can cause memory loss

a form of directed forgetting

(faking it does work)

repression

freudionn concept that memories with threatening content are repressed, protects consciousness from painful memories, it is an unconscious process that keeps you from remembering

NO EVIDENCE TO SUPPORT THIS

dissociative amnesia

inability ot recall important personal events (usually a traumatic or stressful event)

more than typical forgetfulness

-people are troubled by their forgetting, they want tot remember but can’t

better evidence this is real

types of dissociative amnesia: systematized amnesia

amnesia related to a specific traumatic event t

types of dissociative amnesia: localized amnesia

amnesia for a block of time

types of dissociative amnesia: generalized amnesia

amnesia for nearly all of a persons life

dissociative fugue

sudden, unexpected travel from usual surroundings with amnesia of former life

follows a traumatic event

usually time-limited

-person may suddenly remember who they are, after recovery there is then amnesia for the fugue state

-fugue and flight (change in both identity and location)

memory fugue = loss of memories but core identity is intact

regression fugue= reversion to an earlier period of life

dissociative identity disorder

formerly multiple personality disorder

may be amnesia across identities

amnesia asymmetric (more explicit than memory loss) IE= identity A knows about identity B but B doesn’t know of A

unconscious memory is retained though

psychogenic amnesia

most case studies do not rule out alternative explanations

may be malingerining

other potential causes: lack of sleep, organic disruptions, dissociative experience at encoding, normal forgetitnig, repeated experiences, etc….

mental maps were proposed by

Tolman to explain rats in maze learning studies

(tolman was a behaviorist)

place cells

tell absolute location

in hippocampus (CA1)

fire when in a specific location

grid cells

tell of relative space

entorhinal cortex

location inn Euclidean space

border cells

edge of region

entorhinal cortex

sensitive to the presence of borders

PPA

parahiippocampal place area

keeps track of different places

what tells of allocentric space

place, grid, border cells

uses self and others as a reference

egocentric space

left, above, in front, etc…

parietal lobe

used in conceptual thinking (mental timeline, SNARC effect, metaphors, i.e. time etc…)

memory psychophysics

how physical space corresponds to mentality

psychophysical laws and magnitude estimation (Stevans law)

spatial memory is ideal because space can be objectively measured and memory can be directly compared with it)

spatial memory is fairly accurate, with some deviations

spatial memory is compressed relative to actual experience (usually people remember things closer)

compression also occurs in some virtual environments

steven’s law

psychophysical laws and magnitude estimation

category adjustment theory

performance is a combination of: fine grained memories (detailed) and coarse grained mems

initial performance reflects more fine-grained memory and later performance reflects more coarse-grained memory

but as you forget you lose more details becoming more coarse based

metric theory

mental maps directly correspond to the structure of the world

1:1 correspondance between memory and activity

VERY LITTLE EVIDENCE TO SUPPORT THIS

spatial theories

mental maps are spatially organized

-this organization is hierarchical, not metrical (nesting dolls)

memories are distorted based on regions

partially-hierarchical view

mental maps reflect both metric and heirarichal info

spatial priming = people learn map locations and these prime nearby locations

-more priming when close

-estimates of locations clustered based on political/climatctic regions

prior knowledge infulces = effects of borders, even when they no longer exist

-even abstract relations are affected by regions (we track objects more closely gif they are inn our region or not

-number of intervening locations influence estimated differences

priming is affected more by —— distances than —— distance

more by route than Euclidean distance

temporal theories

mental maps organized by order of acquisition

temporal and spatial proximity typically confounded at learning

when deconfounded, temporal priming is observed

hybrid theories

spatial and temporal information contribute to mental maps

people pointed to or named locations

-temporal priming for naming

-spatial priming for pointing

semantic relationships

can influence organization

for example, priming reflects both spatial and semantic distance

spatial gradient of availability

knowledge affects more than memory

ie people learned layout of research center, sentences took longer to read as distance increased

spatial frameworks

regions defined in a particular way

mental rotation

mental maps have a preferred viewing angle

you learn maps better when you

actually interest with the space, also when the map is physically larger

angle error estimates

some people show no effect in this while other people are way off

integrators

best @ mental rotation

efficient and flexible. tend to use both survey and route based knowledge

nonintegrattors

form mennttal maps from experiences but have difficulty reconciling multiple experiences. Do better at mental rotation. Tend to use route-based knowledge.

rely on their individual experiences

imprecise navigators

difficulty forming mental maps from experiences. Do poorly at mental rotation. Struggle with navigation

WM defficient

perspective effect

people increase distances for near locations and decrease them for far locations

aka would say that a location close tot there home city would be further than their home city to a far city

landmarks

memoreis are often distorted towards landmarks, which define regions and are treated as chunks

route perspectives

the view a person has while navigating

-more parietal lobe and caudate nucleus (basal ganglia)

survey perspective

overhead view

more hippocampus

temporal memory

LTM for when events occurred

people are bad at doing this

WHEN not what

temporal distance

saying how long ago something happened (from today? or from set point)

we are not good at this

temporal location

when in the past did something happen

more accurate

-what year did this happen in?

relative time

relative ordering

did this happen before or after…..

better at doing this with similar events

memory age

older memories are harder to locate in time

scale effects

accurate att one level level of scale but wrong at another level

iie= people get the day right but the months wrong

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forward telescoping

older memories seem more recent

backward telescoping

very recent memories seem older

accuracy effects

localization accuracy is associated with memory accuracy

-the more info you have, the better you can place it in time

distance-based processes

estimates reflect memory trace strength

-the older a memory trace, the weaker it is and vice versa

estimates based on overlap between the current context and memory contexts

-greater overlap = newer memory, less overlap = older memory

more likely to see backwards telescoping if you traveled a lot that day

ok

location-based processes

event time directly encoded into the memory (using a biological clock) little evidence this occurs but there are SOME mems with time on them

time estimates involve inferences= use knowledge about events whose time is known (time estimation is reconstructive)

relative time processes

associations formed with prior and subsequent eventntst

esttimates based on older mems are linked to new Onnes

categorical adjustment theory

applied to temporal and spatial memory

temporal compression

we replay events in our mind faster because we are leaving out segments that are not a poignant of interest

NOT because of the actual speed of replay

return trip effectt

only applies to NEW places

-memory for the arrival trip time is longer than memory for the return trip time

-this may be related to ambiguity on the trip out, and familiarity on the trip back