Transcript 8. Exceptional Memory

8 – Exceptional Memory (Savants and Amnesiacs)
Video: 60 Minutes segment (Part 1 only) - 13 min
www.cbsnews.com/video/watch/?id=7166313n&tag=contentMain;contentAux
OR
www.cbsnews.com/video/watch/?id=7166313n&tag=contentBody;housing
OR
www.popeater.com/2010/12/20/marilu-henner-60-minutes-supermemory/?icid=maing%7Cmain5%7Cdl2%7Csec1_lnk1%7C32429
Memory Savants
Highly Superior Autobiographic Memory (HSAM)
HSAM individuals remember virtually every day since childhood
Their intelligence is average or above-average
After 60 Minutes report aired, more than 100 people contacted lab
These Ss were given multiple tests, and about 30 qualified as an “HSAM individual”
Example: S given randomly chosen date since S’s 15th birthday
HSAM
S provided day of week
> 90%
S provided verifiable event within one month
> 80%
(LePort et al., 2012)
Some memory savants have serious intellectual impairments
Subject SS
SS once repeated 70-digit sequence 15 years after hearing it.
“Yes, yes ...This was a series you gave me when we were in your apartment ...You
were sitting at the table and I in the rocking chair ...You were wearing a gray suit and
you looked at me like this...Now, then, I can see you saying ...”
SS relied heavily on vivid imagery, even for digits
“Take the number 1. This is a proud, well-built man; 2 is a high-spirited woman; 3 is a
gloomy person (why, I don’t know); 6 is a man with swollen feet; 7 a man with a
mustache; 8 a very stout woman.”
Some memory savants have serious intellectual impairments
Kim Peek
“He has memorized more than 7,600 books. He can recite
the highways that go to each American city, town or county,
along with the area and zip codes, television stations and
telephone networks that serve them. If you tell him your date
of birth, he can tell you what day of the week it fell on… He is
also developmentally disabled and depends on his father for
many of his basic daily needs. His abilities provided the
inspiration for the character Raymond Babbitt, whom Dustin
Hoffman played in the 1988 movie Rain Man.”
(Treffert & Wallace, 2004)
Amnesia
retrograde amnesia (RA): loss of memories formed before mishap
Example
Patient suffers stroke and loses memories from the last few years
anterograde amnesia (AA): inability to form memories after mishap
Example
Patient suffers stroke and cannot learn new facts from now on
Retrograde Amnesia
RA affects most recent memories (as predicted by consolidation theory).
Healthy Control
RA
RA leaves many kinds of memories intact.
Speech
Motor skills (e.g., ability to play musical instrument)
Review of the film The Bourne Identity
Amnesia is always a dicey plot device, and The Bourne Identity pushes it to
unprecedented heights of illogic. Its protagonist … has no idea who he is. But he has
somehow retained lightning martial-arts reflexes, fluency in a handful of languages,
and the wired instincts of a superspy.
David Edelstein
slate.com
June 14, 2002
RA Case Study
Krickett Carpenter married on September 18, 1993.
She had known her husband for one year.
She was in car accident 10 weeks after her wedding.
After a 21-day coma, she awoke with RA for last 2 years.
Her husband tried to jog her memory with stories & photos.
She resented him and told him that she hated him.
A therapist suggested they begin dating.
On May 25, 1996, they married again.
RA commonly measured by Famous Faces Test
Ss see photos of famous people and try to identify them.
Ideally, famous people’s faces were seen during only a brief period of time.
good choice
bad choice
Experiment
1986 - Patient WH has a stroke, which causes retrograde amnesia
1987 - WH and healthy controls take famous faces test
Controls
WH
(Remple-Clower et al., 1996)
Common Causes of RA (students need not remember these)
Head Trauma
Stroke
Alzheimer’s
Electro-Convulsive Therapy (ECT)
(e.g., Weingartner & Parker, 1984)
Electro-Convulsive Therapy
Patients typically receive 3 treatments per week for several weeks.
Patients are sometimes put to sleep with a short-acting barbiturate.
Succinycholine is administered to paralyze the muscles.
One electrode is placed above each temple (bilateral ECT).
A small current is passed across the brain, causing a seizure.
The current is applied for one second or less.
The duration of the seizure is usually 30 - 60 s.
The patient wakes up 10 to 15 minutes later.
Temporary RA often results.
Source: Papolos
blank
Experiment
1973 – E recruited depressed patients about to undergo ECT (which causes RA).
Patients took multiple-choice test for titles of 1-season TV shows from ’57-’72.
Ss tested just after ECT (RA group) or just before ECT (controls)
Results:
Recent shows
RA < control
Older shows
RA = control
(Squire, Slater, & Chace, 1975)
Anterograde Amnesia
Common causes of AA (students need not remember these)
Head Trauma (N. A.)
Encephalitis (Clive)
Korsakoff’s (Jimmy G.)
Bitemporal Lobectomy (H.M.)
Alzheimer’s
H.M.
Underwent bitemporal lobectomy in 1953 at age 29
Surgery alleviated seizures but caused severe AA.
His conversation, digit span, and IQ were unaffected.
Participated in studies for 55 years until his death in 2008.
Note
Temporal lobe includes hippocampus, which is critical for learning new info
H.M. was aware of his memory difficulty…
“Right now, I’m wondering, have I done or said anything amiss? You see, at this
moment everything looks clear to me, but what happened just before? That’s what
worries me. It’s like waking from a dream; I just don’t remember.”
(Milner, 1970)
Henry Gustav Molaison (1926-2008)
Korsakoff’s
Chronic alcoholism  Poor Nutrition  B1 deficiency  Korsakoff’s
Appears gradually
Most non-memory processes spared
B1 supplements can prevent onset and alleviate symptoms – but not cure it.
Korsakoff’s Syndrome, according to Korsakoff
… the patient gives the impression of a person in complete possession of his faculties;
he reasons about everything perfect well, draws correct deductions from given
premises, makes witty remarks, plays chess or a game of cards…
Only after a long conversation with the patient, one may note that … he remembers
absolutely nothing of what goes on around him…you came in, conversed with him,
and stepped out for one minute; then you come in again and the patient has absolutely
no recollection that you had already been with him. Patients of this type may read the
same page over and over again, sometimes for hours, because they are absolutely
unable to remember what they have read…
(S.S. Korsakoff, as cited by Oscar-Berman, 1980)
Korsakoff’s Case Study
Jimmy G.
At age 49 in 1975, he gave age as 19 and gave year as 1945
Named all nine planets, but was amazed by photo of Earth
(Sacks, 1990)
Oliver Sacks on his first meeting with Jimmy G.
‘And you, Jimmie, how old would you be?’
Oddly, uncertainly, he hesitated a moment, as if engaged in calculation.
‘Why, I guess I’m nineteen, Doc. I’ll be twenty next birthday.’
‘Here,’ I said, and thrust a mirror toward him. ‘Look in the mirror and tell me what you
see. Is that a nineteen-year-old looking out from the mirror?’
He suddenly turned ashen and gripped the sides of the chair. ‘Jesus Christ,’ he
whispered. ‘Christ, what’s going on? What’s happened to me? Is this a nightmare? Am
I crazy? Is this a joke?’ - and he became frantic, panicked.
(Sacks, 1990)
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AA Case Study (Clive – encephalitis)
In his diary, he repeatedly writes,
“Now I am awake for the first time in years.”
When shown notebook,
“I do not know who wrote that, it was not me.”
When describing his life,
“Hell on earth – Ii’s like being dead all the bloody time.”
When asked about the last 10 years,
“I’d like to know what the hell has been going on.”
The Mind (disc 1, segment 10) - Clive Wearing (12:37)
or
www.youtube.com/watch?v=Vwigmktix2Y (about 3 min)
AA Case Study (EP - viral encephalitis)
DVD Scientific American Frontiers “Don’t Forget” (Segment 1)
Start at 3:45
or
www.dailymotion.com/video/xhcfvp_scientific-american-frontiers-don-tforget_tech#.UTe7HRzCfmc
Demo – Complete the word stem with the first word that comes to mind.
Example
SCO_ _
Possible Answers
SCOFF
SCOLD
SCONE
SCOOP
SCOPE
SCORE
SCOUR
SCOUT
Ready …
MEM_ _ _
MEMBER
MEMOIR
MEMORY
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Experiment
Ss read story with word SCOFF.
Later, Ss take 1 of the 2 following kinds of tests
explicit memory test Did story include SCOFF? (yes-no recognition)
implicit memory test Complete word stem S C O _ _
Results
Explicit Test:
AAs
<
Controls
Implicit Test:
AAs
=
Controls
Thus, AAs can demonstrate memory for event if tested indirectly.
(e.g., Warrington & Weiskrantz, 1968, 1970)
Instances of implicit memory in AA patients
Clive
After he developed AA, he was moved to a full-care facility.
Once, while in his room, he was asked where the kitchen was located.
He didn’t know.
Later, when someone asked for tea, Clive walked to the kitchen.
HM
For weeks after he was told that his mom died, HM was noticeably anxious.
When asked what was wrong, HM said, “I think something bad happened to my mom.”
Another instance of implicit memory in AA patient
French female Korsakoff’s Patient (name unknown)
Examined by Swiss psychologist Edouard Claparède (KLAHP – ah – red)
When they first met, Claparède hid a pin in his hand before shaking her hand.
She recoiled in pain.
Later, they met again, but she wouldn’t shake Claparède’s hand.
Claparède repeatedly pressed her for an explanation.
Finally, she said, “Sometimes pins are hidden in people’s hands.”
(Claparède, 1911)
blank
mirror tracing - Ss trace figure they can see only in mirror
Experiment
H.M. and controls practiced mirror tracing.
Across 3 days, both H.M. and controls improved.
Before each session, H.M. insisted he had never performed this task.
Errors
by HM
(Milner, Corkin, & Teuber, 1968)
HM also improved when playing novel songs on piano….
Mirror trace study and other findings suggest following distinction
procedural memory
Subject knows how to
play the piano
ride a bike
mirror draw
declarative memory
Subject knows that
he or she saw the face photo
Paris is in France
he or she has mirror drawn before
Thus, AA patients can acquire procedural memories.
(e.g., Squire, 1990s)
Intriguing study with AA patients
Do we eat because we know how long it’s been since we last ate?
Study
AAs and Controls offered three meals in 1 hour.
Controls refused 2nd and 3rd meals. AAs ate all three.
Conclusion
When and how much we eat depends partly on our memory of when we last ate
(Rozin et al., 1998)
a distinction…
episodic memory
a memory for a particular time and place in your life
“Recall the word list from last week”
“What did you eat last night?”
“Recall the list of 10 fruits I read to you earlier today.”
semantic memory
a memory for a fact without the memory of its source
“Where is Tokyo?”
“When and where was JFK assassinated?”
“What was the name of your high school biology teacher?”
“Name 10 fruits.”
An episodic-semantic double dissociation
Gene
Okay semantic memory (e.g., classmates’ names)
Poor episodic memory (e.g., can’t recall train derailment near his home)
(Tulving et al., 1988)
“Jane”
Okay episodic memory (e.g., her wedding, dad’s death)
Poor semantic memory (e.g., forgot common words, historical events)
(Schacter, 1996)
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One popular taxonomy:
Memory
procedural memory
conditioning
motor skills
semantic memory
declarative memory
episodic memory
Impaired semantic memory is an early sign of Alzheimer’s Disease.
Example
AD patients do very poorly when asked to generate category exemplars.
“Give examples of grocery story items for 1 minute.”
“Give examples of fruits for 1 minute.”
Episodic memory failures (e.g., losing car keys) is a weaker predictor.
Why does AD impair semantic memory?
One explanation: AD destroys links between semantically-related concepts.
The End
Source: brainconnections.com
mirror-tracing - Ss trace figure they can see only in mirror
One popular taxonomy:
conditioning
Memory
prospective memory
retrospective memory
working memory
long-term memory
procedural memory
declarative memory
motor skills
semantic memory
episodic memory