Amnesia from Brain Damage

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Amnesia from Brain Damage
Concussion Shock Lesions Drugs Alcohol
(Korsakoffs syndrome)
Back
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Symptoms Retrograde Amnesia (RA) Anterograde
Amnesia (AA) You usually have
both Retrograde Loss of memory for events
prior to the damage Loss is greatest for time
right before damage Is RA a retrieval or
storage deficit? You can recover from
RA Therefore, it is a retrieval deficit
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RA in rats (Winocurs experiment) (only forget
things for a few days before damage) Phase
1 rats learn to associate a reward with a
particular smell Phase 2
Control Group No lesion to hippocampus
Experimental Group Hippocampus is lesioned either
1,7, or 14 days after learning
control
memory for phase 1
experimental
14 7
1
days since learning
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RA in people (Butlers Cermak
(1986)) Patient P.Z. University professor who
developed amnesia in 1982 (had written
autobiography three years before) Recall of
facts from book
90 50
RA
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Correct
?
?
?
?
?

before 1930 1940
1950 1960 1970 1980
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Anterograde Amnesia Loss of memory for events
after damage Does AA affect STS or
LTS? Baddeley Warrington
serial position
Maintenance in STS is not affected Problem is
with LTS
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Is AA due to failure to transfer to LTS
or failure to retrieve from LTS? If you can
recover from AA, you still can never retrieve the
events that happened while you had
AA Therefore, AA is a failure to transfer
to LTS
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• Not all LTS is affected in amnesia
• Lost
• performance in explicit memory tasks
• (recall, recognition)
• learning new vocabulary
• learning new facts (semantic memory)
• Not Lost
• implicit memory (e.g., stem completion)
• ability to learn new skills
• Milner (1965)

Trace star using mirror
mirror
Amnesics learned as fast as normals
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Cohens Tower of Hanoi Experiment
Normals and amnesics must learn how to solve
problem Result Normals and amnesics learn task
at the same speed Amnesics dont remember
having done the task Amnesics have normal
ability to learn new skills
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A Theory of Amnesia Procedural/Declarative
Theory (Cohen) Amnesia is a disorder of
declarative memory (episodic and semantic
memory) Procedural memory is normal skill
learning o.k. implicit meaning o.k.
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What does the hippocampus do? It allows us to
combine different kinds of knowledge to make new
memories. If the hippocampus is gone, what
happens? Cant form new memories for
events (cant combine parts of events) Cant
store new propositions (cant learn new
facts) (cant remember what you read)
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Why do you lose recent old memories (RA) as well
as the ability to form new memories (AA)? It
takes time (weeks, months) to completely lay down
a new memory. You need the hippocampus to hold
onto recent memories before they are completely
formed.
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What can you do without a hippocampus? Your
STS is o.k. (activation of existing parts
of network) You can strengthen existing
connections in LTS (explains some kinds of
implicit memory) (and why procedural memory is
o.k.)
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• Hypnosis Memory
• 1. Can difficult-to-retrieve memories be
• reached through hypnosis?
• 2. What is the nature of post-hypnotic amnesia.
• Post-hypnotic Amnesia
• loss of memory for events during hypnosis
• caused by suggestion from hypnotist
• Why is it important?
• ? causes of forgetting

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Evans Kihlstrom subjects hypnotized and
given 12 tests heading nodding eyes
close hand lowering arm immobilization finger
lock arm rigidity hands moving
together communication inhibition fly
hallucination eye catalepsy post hypnotic
suggestion to touch ankle post hypnotic amnesia
suggestion subject is awakened
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Perfect Amnesia
20 - 15 - 10 - 5 -
?
Distribution of number of items recalled
?
?
?
of subjects
?
?
?
?
?
?
?
?
?


0 1 2 3 4 5 6 7 8
9 10 11 12
Subjects with perfect amnesia either
think hypnosis was brief or recognize that
theres a gap in their memory.
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Try to recall as many tests as you can
9 8 7 6 5 4 3 2 1
Hi Medium Lo Hypnotizability of Subjects
Hi subjects had vague recall something about a
fly Lo subjects had specific recall You tried
to get me to think there was a fly
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Try to recall as many tests as you can
Now you can remember everything
9 8 7 6 5 4 3 2 1
Recall is equal after amnesia is lifted
Retrieval Failure
Hi Medium Lo Hypnotizability of Subjects
Hi subjects had vague recall something about a
fly Lo subjects had specific recall You tried
to get me to think there was a fly
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Are the memories completely blocked
before amnesia suggestion is lifted? Hull
(1933) Subjects experiencing post-hypnotic amnes
ia show savings in re-learning
TOLD TO FORGET
Group 1 Learn Relearn List A list
A Group 2 Rest Learn list A
TOLD TO FORGET
Group 1 does much better
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Graham Patton (1968) Blocked items still
cause RI
1. Learn list A Learn B Test A 54 2.
Learn list A Rest Test A 87 3.
Learn list A Learn B Test A 46
TOLD TO FORGET
Groups 1 and 2 Hypnotized Group 1 shows as much
RI as Group 3
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Williamson, Johnson Erikson (1965) Subject
hypnotized (high hypnotizable) Learned
list many, pencil, work . . . Awakened Test
recall (could recall almost none) Fragment
completion m _ n _ OLD p e_ _ i _ OLD t _ n
_ NEW Solved fragments much more often for
old words
. . .
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Relation between Recall and Recognition
Phase 1 Phase 2
Hypnotic amnesia occurs in recall, but not really
in recognition. Therefore, it affects the search
phase of retrieval
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Hypnotic Enhancement Alien abduction?? Recall
of former lives?? Police work L.A.P.D.
Study 70 volunteer witnesses hypnotized 77 of
cases got useful information from
hypnosis BUT NO CONTROL GROUP People vs.
Shipley (1982) Supreme court decision Hypnosis
does not contribute to accurate testimony
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Hypnosis leads to more false recall Shaul
(1978) hypnotized subjects showed
more correct recall, but also more false
recall Hypnosis leads to unjustified
confidence Putnam (1979) stop-sign yield-sign
experiment hypnotized subjects were not
more accurate at choosing the correct sign.
But they were more confident
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Details of an Example Study Rudman
(1984) Does hypnosis aid recognition
memory? PHASE 1 (1) Subject enters room (2)
Confederate enters room, apologizes
and leaves (3) Subject hypnotized and tested
for susceptibility (4) Subject awakened and
told they may be asked back PHASE 2 24 highly
hypnotizable subjects called back 1 month later
to the same room 3 groups 8
8 8 Hypnotized Simulators Not
hypnotized
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Subjects told to visualize the last time in
room. Five photographs of people forced
choice recognition and rate confidence Results
Number correct (out of 8) Hypnotized 6 Simu
lators 5 Not Hypnotized 6 No difference in
recognition Number who were
confident (out of 8) Hypnotized 8 Simulators
4 Not Hypnotized 1 Hypnotized subjects were
more confident
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Criterion Shift Hypothesis Hypnosis does not
change the accuracy of memory search processes.
But it does make the subject more willing to
call something a memory. ? False Recall ?
False Alarms in Recognition ? Higher Confidence
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How criterion shift might work Study
List DOG TREE CUP . . .
ON LIST
weaker link
DOG
TREE
CUP
chase
over
has
CAT
LEAVES
SAUCER
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How criterion shift might work Study
List DOG TREE CUP . . .
ON LIST
weaker link
DOG
TREE
CUP
DOG
DOG
TREE
CUP
chase
over
has
CAT
LEAVES
CAT
LEAVES
SAUCER
Memory search works by spreading
activation Recall everything more activated than
some criterion, e.g., 10 units of activation
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How criterion shift might work Study
List DOG TREE CUP . . .
ON LIST
weaker link
RECALL dog tree
DOG
TREE
CUP
DOG
DOG
TREE
CUP
chase
over
has
CAT
LEAVES
CAT
LEAVES
SAUCER
Memory search works by spreading
activation Recall everything more activated than
some criterion, e.g., 10 units of activation
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How criterion shift might work Study
List DOG TREE CUP . . .
Hypnotized Shift criterion down to 5
ON LIST
weaker link
RECALL dog tree cup cat leaves
DOG
TREE
CUP
DOG
DOG
TREE
CUP
chase
over
has
CAT
LEAVES
CAT
LEAVES
SAUCER
More words are recalled because more words are
activated above the lower criterion. cat and
leaves are falsely recalled
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Does music aid performance on cognitive
tasks? The Mozart Effect Rauscher, Shaw Ky
(1993)
Listen to 10 minutes of Mozart
Listen to 10 minutes of repetitive music
10 minutes of Silence
Test on spatial abilities e.g., jig-saw
puzzles mental rotation Result Youre better
after the Mozart
Interpretation Brain regions for musical
processing are shared with regions for spatial
processing. (Music warms up these regions.)
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Is the Mozart Effect For Real? Nantais and
Schellenberg (1999)
Exp 1 Exp 2
Mozart 12.8 Mozart 13.0
score on test
Silence 11.9 Interesting Story 12.9
significant difference no difference
Subjects who preferred Mozart Subjects
who preferred story
Mozart 14.6 11.6
Story 13.2 12.7

• Conclude Theres nothing special about Mozart
  or any
• music for enhancing spatial tasks.
• Doing anything interesting right before the test
  helps
• performance, compared to being bored.

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Repression The essence of repression
lies in simply rejecting and keeping something
out of consciousness. Freud Does this
happen? Of course. Everyday Repression (1)
turn away from unpleasant things poor
encoding Peters (1988) poorer recognition of
nurse who gives inoculation than for a neutral
helper
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• (2) Dont think about unpleasant things
• fewer rehearsals, poor memory
• Meltzer (1950)
• Students forgot more of the
• unpleasant memories that occurred
• over the holidays
• Real Freudian Repression
• painful information is kept out of consciousness
• without the person being aware that they are
• rejecting it

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Two Kinds of Repression
Perceptual Defense
Sensory Memory
STS
Memory Defense
LTS
STS
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Perceptual Defense
TABOO WORD
15 msec
Taboo words must be flashed for a longer duration
before subjects report the word. Conclusion I
ndeterminant Subjects may be less likely to
report seeing a taboo word.
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Is a Taboo Word Effect Perceptual? (Zajonc
(1962)
Group 1 Group 2 see say see say TABOO dog
whore TABOO whore dog CONTROL cat where CONTROL w
here cat TABOO needs no difference longer
exposure Effect is due to the reluctance to
say TABOO words
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Memory Defense
Psychogenic Amnesia Loss of memory from
psychological causes. Loss for specific
situation, or temporary loss of identity Specif
ic Situation Case of Madame D. (Janet). Told
of husbands death (as a joke). Became unable
to remember event. (gradually memory
returned) Loss of Identity (who you are) Fugue
State Sometimes you flee current circumstances
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• Only detailed study of psychogenic amnesia
• P.N. studied by Schacter, Wang, Tulving
• Freeman (1982)
• Episode occurs after grandfathers funeral
• lasted 4 days
• lost most episodic memories
• retained semantic memories
• loss was retrograde more than anterograde

• Organic
• more A.A.
• lose episodic
• semantic
• brain damage

• Psychogenic
• more R.A.
• lose episodic
• personal identity
• traumatic events

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Dissociative Identity Disorder (Multiple
Personalities)
Personalities may not remember events experienced
by other personalities (interpersonality
amnesia) Eich, Macaulay, Lowenstein
Dihle (1997)s experiment Phase 1 Frank is
replaced by Jim Jim reads 20 words Jim does
test of picture fragment completion What is
this?
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Phase 2 Jim is replaced by Henry (Henry is
told Jim heard words. Henry could not recall
ANY of them - NO FREE RECALL) Henry does
cued recall for words that Jim saw. Cue is
first three letters. Henry gets 20 new
words Henry does picture fragment
completion 5 pictures were done by Jim 5
pictures were new
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Picture Fragment Completion
2.0 1.0
improvement from seeing picture before
Jim Jim
Jim Henry
Henry Jim
There is implicit memory (picture
fragment completion) across different
personalities
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• Phase 3
• Jim comes back
• Jim could not free recall any of Henrys
• words
• cued recall for Henrys words
• cued recall for his own words
• (from Phase 1)
• picture fragment completion
• 5 new pictures
• 5 Jim had seen

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Results Cued Recall
50 40 30 20 10
study test
Jim Jim
Henry Jim
Jim Henry
Very poor explicit memory across
different personalities
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Why is interpersonality amnesia found in recall
only? Explicit, episodic memory
Self- Concept 2
episodic memories
Semantic Memory Procedural Memory (perceptual
skills) picture identification