Rajan: “As a child, I used to be so lost in my own thoughts, I would talk to myself. It was hard to fit in. Other kids didn’t know what to make of me.”
Shereshevskii: ultimately, unable to distinguish between conversations he’d heard 5 minutes or 5 years before, he ended up in an asylum
Memory whizzes are often poor at
abstract thinking – generalizing, organizing, evaluating
Savant syndrome: people who are born with severe intellectual disability but show superior ability in one intellectual domain, such as music, art, or mental arithmetic
About 10% of children with autism have savant talents
Analysis of case history of 13 musical savants
All had severe deficits in ability to understand and use language
5 were blind or partially so
All showed an extraordinarily intense interest in performing music beginning at a very young age, usually before age 4 (Treffert, 2008)
Savant syndrome is largely attributable to a seemingly limitless memory
Artistic savants can reproduce exact copies of animals or people or scenes from memory
Musical savants can play back, note for note, long passages of music heard just once
Human calculators can tell you the day of the week that corresponds with any given day of any given month and year, past or future
Suggests that memory capacities are potentially virtually limitless…
Possible to create savant-like memorization skills and artistic abilities in people without autistic traits by disrupting left anterior frontal lobe with TMS
OG Rainman,
Kim Peek, didn’t have two separate hemispheres (no interference) – could read two pages at once
Disruption of global connectivity in neural networks, which results in impairment in certain types of cognitive processing, such as executive function and social cognition
Less global and more local focus
Enhanced connectivity in local brain regions (in part through disruption of connections to prefrontal cortex, which exerts inhibitory control on other cortical regions), resulting in specialization and facilitation of low-level cognitive processing
Participants were shown 2500 slides of faces and places for 10 sec each
Afterwards, they were able to pick out slides they had seen with 90% accuracy (Standing, Conezio, Haber, 1970)
People can remember a substantial amount of material learned decades earlier, including foreign language vocabulary, mathematical knowledge, and information from a psychology course
May not be able to produce information without stimuli (hint)
Three stages of memory processing and forgetting
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Storage decay: information stored in long-term memory gradually fades
In general, storage decay is not as severe as most people tend to think…
Study found that people remembered nearly 40% of foreign language vocabulary, idioms, and grammar after 50 years (and 75% when recognition tests are used)
People who had taken psychology class remembered about 70% of broad general facts and research methods 10 years later (Bahrick, Bahrick, & Wittinger, 1975)
Is storage decay simply due to the passage of time or to interference from new memories formed during this interval? Research suggests that storage decay is primarily due to interference
Participants learned lists of nonsense syllables, then either slept or engaged in normal daily activities
Recall was significantly better when participants slept during the retention interval (Jenkins & Dallenbach, 1924)
The degree to which memories interfere with each other depends on their similarity
Study subjects intermittently
It’s harder to remember a list of letters if all the letters rhyme (V, G, P, D)
Retrieval failure: failure to access information that is stored in long-term memory – “forgotten” material is not completely erased but merely inaccessible
Willem Wagenaar (1986), a Dutch psychologist kept a diary in which he recorded one or two of his experiences every day for six years, resulting in a total of over 2400 incidents
He tested his memory by having a colleague supply some information from each diary entry, then seeing if he could recall the remainder
With a sufficient number of cues, he was able to recall virtually every incident that he had recorded over those six years
Research using digit-word pairs has found that even when information appears to have been entirely forgotten (can neither be recalled or recognized), the information can be relearned much more rapidly the second time around
Even in the case of material that has apparently been “forgotten” , some memory trace is preserved
In addition, even if you can’t actively recall material, it may still be present in your brain in some form and may affect you in various ways
Education is what survives when what has been learned has been forgotten" – B.F. Skinner
Tip-of-the-tongue (TOT) phenomenon: sensation we have when we are confident that we know the word for which we are searching yet cannot recall it
“The signs of it were unmistakable; he would appear to be in mild torment, something like the brink of a sneeze, and if he found the word his relief was considerable”
This subjective feeling of knowing strongly suggests that the forgotten material is really still there, but is this feeling trustworthy?
Research suggests that it is
Even when people cannot remember the word for which they are searching, they often can identify important attributes such as the first letter, the number of syllables, and (in Romance languages) the grammatical gender of a noun
Providing first letter or number of syllables of target word may prompt recall
Lack of appropriate retrieval cues (due to encoding specificity principle)
Ex: Inability to recognize student from your biology class at a dorm party
Context effect: you walk into kitchen to get something, but forget; returning back into the original room, you recall again!
Repression of painful or anxiety-provoking information
There have been documented cases of individuals who had been treated in hospital emergency rooms for childhood sexual abuse, yet these individuals failed to recall the episode when interviewed as adults (Williams, L.M., 1994; Schooler, Bendiksen, & Ambadar, 1997)
Difficult, if not impossible to prove, but the bulk of research evidence suggest that memories are never completely forgotten – they are still present in some form though they may be inaccessible
Penfield study – stimulation of the temporal lobes could lead to vivid recall of (once thought forgotten) memories
Babies only 3 months old can learn that kicking moves a mobile – and retain that learning for a month
However, adults generally can’t remember events that occurred before 2 or 3 years of age –
infantile amnesia
College students recalled details of birth of younger sibling much more accurately if they were three-years-old at the time of the sibling’s birth than if they were two-years-old (Usher & Neisser, 1993)
Recall is poorer if a dramatic change in childhood environment occurred (moving to a different country) or if language spoken changed
Two contributing factors:
We index much of our explicit memory with a command of language that young children do not possess
The hippocampus is one of the last brain structures to mature, and as it does, more gets retained (Akers, Martinez-Canabal, Restivo et al., 2014)
Study found that 10-year-olds could consciously recognize (amid other photos) only 1 in 5 of their former preschool classmates
However, their physiological responding (skin perspiration) was greater when shown their former classmates – even when not consciously recognized (Newcombe, Drummey, Fox et al., 2000)
You have been mine before, How long ago I may not know: But just when at that swallow’s soar Your neck turned so, – Dante Gabriel Rossetti
Reconsolidation: Whenever we retrieve a memory, the brain rewrites it a bit – it is slightly altered chemically by a new protein synthesis that links it to our present concerns and understanding
Every thought we think rewires our brain to some extent, changing its structure and/or function
Because the processes involved in memory reconstruction are unconscious, we can be convinced that our memories are accurate even when they are partially or even wholly wrong (Offer, Kaiz, Howard et al., 2000)
73 ninth-grade boys were interviewed, then reinterviewed 35 years later
When asked to recall how they had reported their attitudes, activities, and experiences, most men performed at a rate no better than chance
1 in 3 now remembered having received physical punishment though, as ninthgraders, 82% said they had
Researchers are experimenting with manipulating reconsolidation to treat people with traumatic memories
People are asked to recall the traumatic or negative experience
Consistency Bias (or
hindsight bias): we tend to reconstruct the past to be more consistent with our current feelings and beliefs
People asked how they felt 10 years ago about marijuana or gender issues recalled attitudes closer to their current views than to the views they had actually reported a decade earlier (Markus, 1986; Mazzoni & Vannucci, 2007)
Couples who were re-interviewed after eight months remembered their past feelings about their partners as matching their current feelings more than had actually been the case (McFarland & Ross, 1987)
Misinformation effect: incorporating misleading information presented after an event into one’s memory of the event
Study in which people were shown a film depicting a traffic accident, then either asked how fast the cars were going when they hit each other or how fast they were going when they smashed into each other
People gave faster speed estimates when word smashed was used
When asked a week later whether there was any broken glass in the accident, people who heard ‘smashed’ were much more like to answer yes (Loftus & Palmer, 1974)
Studies show that it’s not all that hard to plant a false memory in a person’s mind
Participants in one study were falsely led to “recall” that they had knocked over a punch bowl at a wedding when they were six-years-old (Hyman, Husband, & Billings, 1995)
In a more recent study, 70% of students reported a detailed false memory of having committed a crime, such as assaulting someone with a weapon (Shaw & Porter, 2015)
Memories are particularly easy to implant if person is asked to visualize event
Overconfidence in
flashbulb memories (memory for the situation in which you first learned a very surprising and emotionally arousing event)
People were interviewed one day after the explosion of the space shuttle Challenger and again, three years later
Participants reported having vivid memories of what they had been doing when they heard the news and were very confident that their memories were accurate
However, these recollections were often wrong! Average accuracy score was only 3 on a 7-point scale, and 25% of participants were wrong on every single detail (Neisser & Harsh, 1992)
Flashbulb memories are typically no more accurate than memories for other events – people’s confidence in their testimony is not strongly correlated with accuracy
It is estimated that 2000 to 10,000 people are wrongfully convicted each year in the U.S. on the basis of eyewitness testimony
Case of man who spent 11 years in prison for rape before they found out on the basis of DNA testing that he couldn’t have been the assailant
One study examined 62 cases in which innocent people were later exonerated on the basis of DNA evidence (including 8 in which person had been sentenced to death)
In 52 of these 62 cases, the crucial evidence leading to conviction had come from eyewitnesses (Scheck, Neufield, & Dwyer, 2000)
Dilema: Eyewitness testimony is also the #1 factor that leads to conviction too
Witness’ attention was stressed and/or distracted (e.g., by presence of a gun)
Plausible misinformation was given during questioning
Witness is pressured to give a specific response
Witness is given positive feedback (could be even a simple “OK”)
Confidence of a witness is a very poor predictor of whether a memory is accurate; nevertheless juries are strongly influenced by confidence (Busey, Tunnicliff, Loftus et al., 2000)
Experiment: Picture, in your mind, a stranger whom you’ve seen recently (e.g., waiter or waitress who served you recently or the person who sat next to you on the bus)
Do you think you could pick that person out of a police lineup?
What if I first asked you to write down in as much detail as you can about what that person looks like? Do you think this will improve or impair your ability to pick that face out of a lineup?
Answer: Impair
Attempt to verbalize memories/insights may in fact impair your ability to recall what was actually there (Dodson, Johnson, & Schooler, 1997)
Experiment: Participants are shown series of faces and asked to make either
Holistic judgments (Does she look like an accountant?) OR
Judgments about specific features (Does he have bushy eyebrows?)
Which condition resulted in better performance on recognition test?
Answer: The holistic judgments condition (Baddeley, 1979)
Expert police sketch artist focus on asking witness about emotional characteristics of suspect in sketching portrait (Jonathan Schooler)
Own-race bias or
other race effect: People are more accurate in identifying members of their own race
Analyses of people’s descriptions of faces for police artist show that people tend to describe members of their own race more in terms of emotions or personality characteristics
Effect seems to be primarily due to experience
People of European descent more accurately identify individual African faces if they have watched a great deal of basketball on television, exposing them to many African-heritage faces (Li, Dunning, & Malpass, 1998)
Warn witness that perpetrator might not be present
Witnesses are often convinced that culprit must be present in a lineup and so simply pick the person who most closely resembles their memory of the perpetrator
Researchers found that telling witnesses that perpetrator might not be present reduced number of innocent people who were identified incorrectly by 42%
Research has demonstrated that some people may indeed forget about painful childhood memories and recall it years later
There have been documented cases of individuals who had been treated in hospital emergency rooms for childhood sexual abuse, yet these individuals failed to recall the episode when interviewed as adults (Williams, L.M., 1994; Schooler, Bendiksen, & Ambadar, 1997)
Case of a college professor, Ross Cheit, who woke up one morning and suddenly remember having been molested by camp counselor – counselor confessed when confronted with the crime (Schacter, 1996)
Many reported incidences of abuse probably never happened
Research has shown that it is not all that hard to implant false memories
Study on implanting false memories in children (Ceci, 1995)
An adult repeatedly asked child to think about several real and fictitious events
“Think hard, and tell me if this ever happened to you. Can you remember going to the hospital with a mousetrap on your finger?”
After 10 weeks, a new adult asked the same question
58% of preschoolers produced false (and often vivid) stories regarding one or more events they had never experienced
When reminded that his parents had told him several times that the mousetrap incident never happened – that he had imagined it, child protested, “But it really did happen. I remember it!” (Weiten, W., 1998)
Children have particular difficulty with source monitoring
Ex: they sometimes recall that they had performed a task that someone else had actually performed
According to Freud, children’s attention tend to be focused on erogenous zones
3-year-olds were asked to show on anatomically correct dolls where pediatrician had touched them
55% who had not received genital examinations pointed to either genital or anal areas (Ceci & Bruck, 1993, 1995)
Under ideal circumstances, children’s reports can be trustworthy
Reports may be unreliable when
Children are young
They have been supplied with suggestive questions
Interviewers ask questions in a highly emotional tone or use complex language (Pipe, Lamb, Orbach et al., 2004)
Nine-year-old girl said she had seen suspect with blood spattered on his shirt and hands
Two weeks before scheduled execution, girl admitted that she wasn’t certain whether the red stain was blood or salsa (suspect had worked in a salsa factory)
She said that she had originally testified against man because her mother had told her that he was a bad man, and people encouraged her to be more certain of her testimony than she was (Ceci & Bruck, 1995)
Positively correlated with socioeconomic level and education
Positively correlated with stress and fatigue
More common in people who travel
Scientific explanations (Alan S. Brown, 2003):
Dual processing explanation
Incoming sensory data follow several different pathways
A slight alteration in transmission speed in one pathway could cause the brain to interpret the data as two separate experiences
Attentional explanation
A fully processed perceptual experience that matches a minimally processed impression received moments earlier produces a strong feeling of familiarity
The original impression may not have been fully processed due to a physical distraction or a mental distraction, such as preoccupation with other thoughts
Memory explanation:
Implicit familiarity without explicit recollection
Ex: Seeing a lamp in your friend’s apartment that is similar or identical to one that used to be in your aunt’s house
