Autobiographical memory: Research reports

The role of emotion

May 2006

Life-defining events remembered more favorably

A study has found that when people feel an event has had a large impact on them, they downplay the negative and emphasize the positive. For such significant events, when asked to reflect on negative events, people reported less negative emotion and more positive emotion compared to how they recalled feeling at the time. Similarly, for positive events, people reported more positive emotion and less negative emotion compared to how they recalled feeling at the time.
The report was published in the June issue of the Journal of Personality. Full reference
http://www.eurekalert.org/pub_releases/2006-05/bpl-omw051606.htm

February 2005

Why traumatic memories have the power they do

In the first imaging study to look at retrieval of emotional memories after a long period (one year after encoding), researchers found that people did recall emotional images, both pleasant and unpleasant, better than emotionally-neutral images. This recall was associated with higher activity in both the amygdala and the hippocampus. The synchronicity of activity between these two regions suggested that each region triggers the other, creating a self-reinforcing "memory loop" in which an emotional cue might trigger recall of the event, which then loops back to a re-experiencing of the emotion of the event. The findings suggest why people subject to traumatic events may be trapped in a cycle of emotion and recall that aggravates post-traumatic stress disorder, and may also suggest why therapies in which people relive such memories and reshape perspective to make it less traumatic can help people cope with such memories.
The paper was published online February 9 in the Proceedings of the National Academy of Sciences. Full reference
http://www.eurekalert.org/pub_releases/2005-03/du-ems030805.htm

August 2004

Mood affects eyewitness accuracy and reasoning

A new study suggests people in a negative mood provide more accurate eyewitness accounts than people in a positive mood state. Moreover, people in a positive mood showed poorer judgment and critical thinking skills than those in a negative mood. The researchers suggest that a negative mood state triggers more systematic and attentive, information processing, while good moods signal a benign, non-threatening environment where we don't need to be so vigilant.
The study is to be published in the Journal of Experimental Social Psychology.
http://www.eurekalert.org/pub_releases/2004-08/uons-era082004.htm

June 2003

How memory helps make life pleasant

Surveys consistently show that people are generally happy with their lives. A review of research into autobiographical memory suggests why - human memory is biased toward happiness. Across 12 studies conducted by five different research teams, people of different racial and ethnic backgrounds and of different ages consistently reported experiencing more positive events in their lives than negative events, suggesting that pleasant events do in fact outnumber unpleasant events because people seek out positive experiences and avoid negative ones. Our memory also treats pleasant emotions differently from unpleasant emotions. Pleasant emotions appear to fade more slowly from our memory than unpleasant emotions. This is not repression; people do remember negative events, they just remember them less negatively. Among those with mild depression, however, unpleasant and pleasant emotions tend to fade evenly.
The findings are published in the June issue of Review of General Psychology. Full reference
Full text of the article is available at http://www.apa.org/journals/gpr/press_releases/june_2003/gpr72203.html
http://www.eurekalert.org/pub_releases/2003-06/apa-rtg060203.htm

November 2002

Excitement helps memory for unrelated events

We’ve long known that emotionally charged events are easier to remember than boring ones. New research suggests that the reason is the flood of emotion, not the personal meaningfulness of the event. Subjects asked to memorize a list of words did better if they subsequently watched a gory film of a bloody dental extraction, rather than a dull video on tooth brushing.
The study was reported at the Society for Neuroscience annual meeting in Orlando, Florida. Full reference
http://www.nature.com/nsu/021104/021104-5.html

September 2000

Suppressing your expression of emotion affects your memory for the event

The way people go about controlling their reactions to emotional events affects their memory of the event. In a series of experiments designed to assess the effect of suppressing the expression of emotion, it was found that, when people were shown a video of an emotional event and instructed not to let their emotions show, they had poorer memory for what was said and done than did those people who were given no such instructions. However, when shown slides of people who had been injured, people in both groups were equally good at picking which in an array of subtly different versions of each slide had been shown earlier - but when prompted to recall information that had been presented verbally with each slide, those in the suppression group again remembered fewer details. People who were asked to adopt the neutral attitude of a medical profession however, performed better than the control group on nonverbal recall, indicating the regulation of emotions via reappraisal was not associated with any memory impairment. These experimental results were supported by a naturalistic study.
The study was reported in the September issue of the Journal of Personality and Social Psychology. Full reference
Full text of this article is available at http://www.apa.org/journals/psp/psp793410.html
http://www.sciencedaily.com/releases/2000/09/000913203335.htm

February 2005

Positive emotions help people see big picture details

A study involving 89 students, who watched a video designed to induce either joy and laughter, anxiety, or no emotion, found that those who were in a positive mood had a far greater ability to recognize members of another race when briefly shown photos of individuals. In the absence of positive emotions, subjects recognized members of their own race 75% of the time but only recognized members of another race 65% of the time. Their ability to recognize members of their own race was unaffected by their emotional state.
The findings will appear in an upcoming issue of Psychological Science.
http://www.eurekalert.org/pub_releases/2005-02/uom-pes020105.htm

June 2004

Stress reactions no guarantee of authenticity

Physical stress reactions have often been taken as evidence for the authenticity of a memory. A recent study investigated people with “memories” of alien abductions (on the grounds that these are the memories least likely to be true) and found that those who believed they had been abducted by aliens responded physically to recall of that memory in the same way as to recall of other, true, stressful events. The finding suggests that a person’s reaction to a memory is no evidence for whether or not it truly happened.
The study was published in the July issue of Psychological Science. Full reference
http://www.eurekalert.org/pub_releases/2004-06/aps-ptw062104.htm

Stress no aid to memory

Numerous studies have questioned the accuracy of recall of traumatic events, but the research is often dismissed as artificial and not intense enough to simulate real-life trauma. A new study has used real stress: 509 active duty military personnel enrolled in survival school training were deprived of food and sleep 48 hours and then interrogated. A day later, only 30% of those presented with a line-up could identify the right person, only 34% identified their interrogator from a photo-spread and 49% from single photos shown sequentially (putting the interrogator in the same clothing boosted correct identification to 66%). Thirty people even got the gender wrong. Those subjected to physical threats (half the participants) performed worse.
The report appeared in the May/June issue of the International Journal of Law and Psychiatry. Full reference
http://www.newscientist.com/news/news.jsp?id=ns99995089
http://www.eurekalert.org/pub_releases/2004-06/yu-emp060304.htm
http://www.eurekalert.org/pub_releases/2004-06/ns-mfy060904.htm

May 2004

Memories of crime stories influenced by racial stereotypes

The influence of stereotypes on memory, a well-established phenomenon, has been demonstrated anew in a study concerning people's memory of news photographs. In the study, 163 college students (of whom 147 were White) examined one of four types of news stories, all about a hypothetical Black man. Two of the stories were not about crime, the third dealt with non-violent crime, while the fourth focused on violent crime. All four stories included an identical photograph of the same man. Afterwards, participants reconstructed the photograph by selecting from a series of facial features presented on a computer screen. It was found that selected features didn’t differ from the actual photograph in the non-crime conditions, but for the crime stories, more pronounced African-American features tended to be selected, particularly so for the story concerning violent crime. Participants appeared largely unaware of their associations of violent crime with the physical characteristics of African-Americans.
The study was reported in the March issue of the Journal of Communication. Full reference
http://www.eurekalert.org/pub_releases/2004-05/ps-rmo050504.htm

Where are our personal experiences stored in the brain?

May 2005

Long-term storage of autobiographical memories

By studying in detail the ability of patients with selective brain damage to recall events in their past, researchers have helped settle a long-standing controversy about whether long-term memory of one's personal experiences continue to be stored in the medial temporal lobe, or whether they gradually become independent of this area. The evidence from this new study suggests that autobiographical memories gradually become distributed throughout the neocortex.
The research was published in the June 2 issue of Neuron. Full reference
http://www.eurekalert.org/pub_releases/2005-06/cp-wlm052605.htm

November 2004

What happens in the brain when we remember our own past?

A new imaging study has managed to distinguish between two types of autobiographical memory — the “facts” of our lives (e.g., knowing that you attended your cousin’s wedding last year), and the experiences of our lives (e.g., remembering traveling to the wedding, the events and people). As with much autobiographical memory research, the study used a diary-type procedure, whereby volunteers spent several months recording the events of their lives on a micro cassette recorder, as well as personal facts of their lives. These recordings were then played back to the volunteers while their brains were being scanned with fMRI. The results showed that the two types of autobiographical memory engaged different parts of the brain, even when the memories concerned the same contents. Recall of personal episodic memories more strongly engaged parts of the frontal lobes involved in self-awareness, as well as areas involved in visual memory.
The study was published in the November issue of the Journal of Cognitive Neuroscience. Full reference
http://www.eurekalert.org/pub_releases/2004-11/bcfg-whi111604.htm

September 2004

New technique sheds light on autobiographical memory

A new technique for studying autobiographical memory has revealed new findings about autobiographical memory, and may prove useful in studying age-related cognitive impairment. Previous inconsistencies between controlled laboratory studies of memory (typically, subjects are asked to remember items they have previously seen in the laboratory, such as words presented on a computer screen) and studies of autobiographical memory have seemed to indicate that the brain may function differently in the two processes. However, such differences might instead reflect how the memories are measured. In an effort to provide greater control over the autobiographical memories, volunteer subjects were given cameras and instructed to take pictures of campus scenes. The subjects were also instructed to remember the taking of each picture as an individual event, noting the physical conditions and their psychological state, such as their mood and associations with the subject of the images. The subjects were then shown a selection of campus photos they had not taken. While their brains were scanned, they were then shown a mix of their own photos with those they had not taken, and asked to indicate whether each photo was new, seen earlier in the lab, or one they had taken themselves. The researchers found that recalling the autobiographical memories activated many of the same brain areas as laboratory memories (the medial temporal lobe and the prefrontal cortex); however, they also activated brain areas associated with "self-referential processing" (processing information about one's self), and regions associated with retrieval of visual and spatial information, as well as showing a higher level of activity in the recollection areas in the hippocampus.
The report will appear in the November issue of the Journal of Cognitive Neuroscience.
http://www.eurekalert.org/pub_releases/2004-09/du-blm092904.htm

June 2001

The chunking of our lives: the brain "sees" life in segments

We talk about "chunking" all the time in the context of memory. But the process of breaking information down into manageable bits occurs, it seems, right from perception. Magnetic resonance imaging reveals that when people watched movies of common, everyday, goal-directed activities (making the bed, doing the dishes, ironing a shirt), their brains automatically broke these continuous events into smaller segments. The study also identified a network of brain areas that is activated during the perception of boundaries between events. "The fact that changes in brain activity occurred during the passive viewing of movies indicates that this is how we normally perceive continuous events, as a series of segments rather than a dynamic flow of action."
The study is published in the June 2001 issue of Nature Neuroscience. Full reference
http://www.eurekalert.org/pub_releases/2001-07/aaft-bp070201.htm

Why some people remember events better than others

January 2003

Gene linked to poor episodic memory

Brain derived neurotrophic factor (BDNF) plays a key role in neuron growth and survival and, it now appears, memory. We inherit two copies of the BDNF gene - one from each parent - in either of two versions. Slightly more than a third inherit at least one copy of a version nicknamed "met," which the researchers have now linked to poorer memory. Those who inherit the “met” gene appear significantly worse at remembering events that have happened to them, probably as a result of the gene’s effect on hippocampal function. Most notably, those who had two copies of the “met” gene scored only 40% on a test of episodic (event) memory, while those who had two copies of the other version scored 70%. Other types of memory did not appear to be affected. It is speculated that having the “met” gene might also increase the risk of disorders such as Alzheimer’s and Parkinsons.
The study was reported in the January 24 issue of Cell. Full reference
http://www.nih.gov/news/pr/jan2003/nimh-23.htm
http://www.eurekalert.org/pub_releases/2003-01/niom-hga012203.htm
http://news.bbc.co.uk/1/hi/health/2687267.stm

June 2002

Childhood "amnesia" linked to vocabulary

"Childhood amnesia" is the term given to the well-known phenomenon of our almost complete lack of memory for the experiences of our very early childhood. Exactly why it occurs is long been a subject of debate. New research suggests the answer may lie in the very limited vocabulary of very young children. A study of 2- and 3-year-old children found that children can only describe memories of events using words they knew when the experience occurred. When asked about the experimental situation (involving a "magic shrinking machine") a year later, the children easily remembered how to operate the device, but were only able to describe the machine in words they knew when they first learned how to operate it.
The findings appeared in the May 3 issue of the journal Psychological Science. Full reference

October 2001

Left-handers may be better at remembering events

A recent study that compared episodic memory (for events) and implicit memory (for facts) concluded that the two hemispheres of the brain work together to help us remember events, while facts are processed in one hemisphere alone. It seems that people whose brains' halves work together more actively (people with left-handedness in their families - although not necessarily left-handed themselves) remember events better than they remember facts. These findings also help explain why children don't remember events until about age 4, when the fibers connecting the hemispheres fully develop.
This research was reported in the October issue of Neuropsychology. Full text of the article is available at http://www.apa.org/journals/neu.html Full reference http://www.apa.org/releases/leftymemory.html

June 2001

Cultural differences in autobiographical memory

American adults and preschool children recall their personal memories in a way that is consistently different from the way indigenous Chinese do, according to recent study. "Americans often report lengthy, specific, emotionally elaborate memories that focus on the self as a central character. Chinese tend to give brief accounts of general routine events that center on collective activities and are often emotionally neutral."From an earlier study (published in Memory, Vol. 8, 2000), it is thought that these differences in remembering (with their implications for sense of self) reflect the different conversational styles between mother and child found in these two cultures.
The study appears in the August issue of the Journal of Personality and Social Psychology.
http://www.eurekalert.org/pub_releases/2001-06/aaft-ach062601.htm

May 2001

Amygdala may be critical for allowing perception of emotionally significant events despite inattention

We choose what to pay attention to, what to remember. We give more weight to some things than others. Our perceptions and memories of events are influenced by our preconceptions, and by our moods. Researchers at Yale and New York University have recently published research indicating that the part of the brain known as the amygdala is responsible for the influence of emotion on perception. This builds on previous research showing that the amygdala is critically involved in computing the emotional significance of events. The amygdala is connected to those brain regions dealing with sensory experiences, and the theory that these connections allow the amygdala to influence early perceptual processing is supported by this research. Dr. Anderson suggests that “the amygdala appears to be critical for the emotional tuning of perceptual experience, allowing perception of emotionally significant events to occur despite inattention.”
The study is reported in the May 17 issue of Nature. Full reference
http://www.eurekalert.org/pub_releases/2001-05/NYU-Infr-1605101.htm

How we create false memories

February 2005

How the brain creates false memories

An imaging study has shed new light on how false memories are formed. The study involved participants watching series of 50 photographic slides that told a story. A little later, the subjects were shown what they thought was the same sequence of slides but in fact containing a misleading item and differing in small ways from the original. Two days later, the subjects’ memories were tested. It was found that, during the original encoding (the 1^st set of slides), activity in the hippocampus and perirhinal cortex was greater for true than for false memories, while during the misinformation phase (2^nd set), the activity there was greater for false memories. In other regions, such as the prefrontal cortex, activity for false memories tended to be greater during the original event. Activity in the prefrontal cortex may be correlated to encoding the source, or context, of the memory. Thus, weak prefrontal cortex activity during the misinformation phase indicates that the details of the second experience were poorly placed in a learning context, and as a result more easily embedded in the context of the first event, creating false memories.
The report appeared in the January issue of Learning & Memory. Full reference
http://www.eurekalert.org/pub_releases/2005-02/cshl-htb012805.htm

October 2004

How false memories are formed

An imaging study has attempted to pinpoint how people form a memory for something that didn't actually happen. The study measured brain activity in people who looked at pictures of objects or imagined other objects they were asked to visualize. Three brain areas (precuneus, right inferior parietal cortex and anterior cingulate) showed greater responses in the study phase to words that would later be falsely remembered as having been presented with photos, compared to words that were not later misremembered as having been presented with photos. Brain activity produced in response to viewed pictures also predicted which pictures would be subsequently remembered. Two brain regions in particular -- the left hippocampus and the left prefrontal cortex -- were activated more strongly for pictures that were later remembered than for pictures that were forgotten. The new findings directly showed that different brain areas are critical for accurate memories for visual objects than for false remembering -- for forming a memory for an imagined object that is later remembered as a perceived object.
The study was published in the October issue of Psychological Science. Full reference
http://www.eurekalert.org/pub_releases/2004-10/nu-nrp101404.htm
http://www.northwestern.edu/newscenter/stories/2004/10/kenneth.html

March 2004

Photos facilitate "recovery" of false memories

Another study demonstrating the ease with which people can be persuaded to accept a fabricated childhood memory. A Canadian study found that use of photographs (used by some psychotherapists as memory cues for the "recovery" of patients' possible childhood sexual abuse) resulted in an astounding two-out-of-three participants accepting a concocted false grade-school event as having really happened to them. The study involved 45 first year psychology students being told three stories about their grade-school experiences and asked about their memories of them. Two of the accounts were of real events advised by the participant's parents; the third was fictitious. Participants were encouraged to recall the events through a mix of guided imagery and "mental context re-instatement"--the mental equivalent of putting themselves back in their grade-school shoes. Half of the participants were also given their real grade one class photo. While a quarter or so of the participants without a photo claimed to have some memory of the false event, 67% of those shown a photo claimed some memory.
The report appeared in the March issue of Psychological Science. Full reference
A PDF version of the article can be found at http://web.uvic.ca/psyc/lindsay/cv/index.html#publications
http://www.eurekalert.org/pub_releases/2004-03/nsae-cwb033104.htm

November 2003

Initial steps in a test for false memory

It appears that sensory areas of the brain might be more revealing than the areas specific involved in memory when trying to tell whether a given memory is true or false. An imaging study has found that when people correctly recognised a shape, a visual area called the ventral temporal cortex was more active than when people mistakenly identified a shape that was only similar. In similar vein, auditory regions of the brain became more active during accurate recognition of words.
http://www.newscientist.com/news/news.jsp?id=ns99994363
http://www.eurekalert.org/pub_releases/2003-11/sfn-sfb110803.htm

July 2003

Impact of 'generative learning' on false memories

"Generative learning " refers to the idea that people remember things better when actively involved in forming an idea. For example, if an individual is given a clue and asked to provide a one-word answer, he or she will remember that word better than if simply given the word and told to memorize it. A recent study looked at the effect generative learning might have on the formation of false memories. Participants were given a list of words to memorize – some of the words were complete, and others were missing one letter. Complete and incomplete words came from different subject categories. After the learning period, participants were given a "distracting" math quiz, then presented with a list of words. This list included some words that had not been included in the original list but were related to the subject categories used. It was found that people were far more likely to mistakenly identify a word as one they had seen before, if it was from the same category as the complete words. In another experiment, participants were given a list of words that were missing one letter and could be either of two words, depending on what letter filled in the blank. Some of the participants were given a positive clue, such as "a tennis shoe," and asked to fill in the blank. Others were given a negative clue, such as "not part of a stereo." People were more likely to remember words when given a negative clue than a positive one, and were also less likely to falsely remember a word.
The research was published in the July issue of Journal of Experimental Psychology: Learning, Memory and Cognition.
Full reference
http://www.eurekalert.org/pub_releases/2003-07/tu-tup072403.htm

February 2003

Remembering imagined actions as real

The latest from Elizabeth Loftus, guru of false memory research. In this study, volunteers performed a variety actions from the commonplace (flipping a coin) to the bizarre (crushing a Hershey's kiss with a dental floss container). Later, they were asked to imagine additional actions, such as kissing a frog. At a future time, participants were asked to recall their actions on that specific day. It was found that 15% of the volunteers claimed they had actually performed some of the actions they had only imagined.
The research was reported at the "Remembering Traumatic Experiences in Childhood: Reliability and Limitations of Memory" symposium at the American Association for the Advancement of Science Annual Meeting in Denver, on February 16.
http://www.eurekalert.org/pub_releases/2003-02/uoc--fkf021303.htm

September 2001

Hypnosis may give false confidence in inaccurate memories

A new study suggests that hypnosis doesn't help people recall events more accurately - but it does tend to make people more confident of their inaccurate memories. Researchers asked college students, including some who were under hypnosis, to give the dates of 20 national and international news events from the past 11 years. Those who were hypnotized were no more accurate than others in choosing the correct dates. However, those who were hypnotized were more reluctant to change their answers when they were told they might be wrong. Joseph Green, co-author of the study and associate professor of psychology at Ohio State University's Lima campus, said the results of the new study don't mean that hypnosis has no value. Any kind of technique used to retrieve memories - including the use of diaries or drugs - will produce inaccurate memories. However, the difference is that people tend to have more faith in hypnosis than they do in other memory techniques.
The results of this study were presented in San Francisco at the annual meeting of the American Psychological Association on August 26. Reference
http://www.eurekalert.org/pub_releases/2001-08/osu-hmg082201.htm

June 2001

New evidence shows how easily false memories can be created

About one-third of the people who were exposed to a fake print advertisement that described a visit to Disneyland and how they met and shook hands with Bugs Bunny later said they remembered or knew the event happened to them.
The study was presented the annual meeting of the American Psychological Society on June 17 in Toronto and at a satellite session of the Society for Applied Research in Memory and Cognition in Kingston, Ontario.
http://www.eurekalert.org/pub_releases/2001-06/UoW-tIta-1006101.htm

May 2001

Magnetic resonance imaging reveals difference between true and false memories

Tests of the human capacity for believing false memories have typically involved giving subjects a list of associated words and then testing their memory for these words by offering a new list which includes not only the previous words but also related words that were not presented earlier. A strong tendency to falsely recognize such words is characteristically found, but intriguingly, the subjects also tend to rate true items higher than false items in terms of sensory details. This suggests that, although people truly believe their false memories, part of the brain at least, recognizes that they are not as "real" as true memories. This has been something of a conundrum in false memory research.
A recent study used magnetic resonance imaging to monitor brain activity during such testing. The memory experience was made richer by having the words read on video by alternating male and female speakers. The findings were the same as in previous studies - subjects rejected new words, but falsely recognized false words related to the true words. The brain scans revealed that different parts of the brain processed true and false memories differently. The region that processes perceptual information, such as the speaker appearance and voice, was more activated for true memories.
The study was reported in an article in the April 10 issue of The Proceedings of the National Academy of Sciences. Full reference
http://www.eurekalert.org/pub_releases/2001-05/DU-Rhun-0305101.htm

How familiarity can mislead

June 2006

People remember prices more easily if they have fewer syllables

The phonological loop — an important component of working memory —can only hold 1.5 to 2 seconds of spoken information. For that reason, faster speakers have an advantage over slower speakers. Now a consumer study reveals that every extra syllable in a product's price decreases its chances of being remembered by 20%. Thus, people who shorten the number of syllables (e.g. read 5,325 as 'five three two five' as opposed to 'five thousand three hundred and twenty five') have better recall. However, since we store information both verbally and visually, it’s also the case that unusual looking prices, such as $8.88, are recalled better than typical looking prices.
The study will appear in the September issue of the Journal of Consumer Research. Full reference
http://www.sciencedaily.com/releases/2006/06/060623001231.htm
http://www.eurekalert.org/pub_releases/2006-06/uocp-prp062206.htm

Increasing consumer preferences by manipulating memory

In two experiments, people who had to solve an anagram before seeing a target brand, they were more likely to claim to have seen the brand before, and to prefer it over competing brands.
The study was published online 29 June in Applied Cognitive Psychology. Full reference
http://www.eurekalert.org/pub_releases/2006-06/jws-icp062606.htm

May 2005

Older adults more likely to "remember" misinformation

In a study involving older adults (average age 75) and younger adults (average age 19), participants studied lists of paired related words, then viewed new lists of paired words, some the same as before, some different, and some with only one of the two words the same. In those cases, the "prime" word, which was presented immediately prior to the test, was plausible but incorrect. The older adults were 10 times more likely than young adults to accept the wrong word and falsely "remember" earlier studying that word. This was true even though older adults had more time to study the list of word pairs and attained a performance level equal to that of the young adults. Additionally, when told they had the option to "pass" when unsure of an answer, older adults rarely used the option. Younger adults did, greatly reducing their false recall. The findings reflect real-world reports of a rising incidence of scams perpetrated on the elderly, which rely on the victim’s poor memory and vulnerability to the power of suggestion.
A full report appeared in the May issue of the Journal of Experimental Psychology (JEP): General. Full reference
Full text of the article is available at http://www.apa.org/journals/releases/xge1342131.pdf.
http://www.eurekalert.org/pub_releases/2005-05/apa-gmc051005.htm

March 2005

Repeated product warnings are remembered as product recommendations

Warnings about particular products may have quite the opposite effect than intended. Because we retain a familiarity with encountered items far longer than details, the more often we are told a claim about a consumer item is false, the more likely we are to accept it as true a little further down the track. Research also reveals that older adults are more susceptible to this error. It is relevant to note that in the U.S. at least, some 80% of consumer fraud victims are over 65.
The report appeared in the March 2005 issue of the Journal of Consumer Research. Full reference
http://www.eurekalert.org/pub_releases/2005-03/uocp-nrr032905.htm

August 2003

You may not be able to recall it, but it influences you anyway

“Forgetting” doesn’t mean the memory is erased from your brain. “Forgotten” information may in fact influence you more than it would if it hadn’t been forgotten — because you’re unaware of the influence. This somewhat alarming possibility has been raised by a recent study in which college students studied lists of nonfamous and famous names. Some participants were told to remember the nonfamous names, while the others were told to forget them. Later, both groups were asked to judge whether or not a name was famous from a mixed list of famous and nonfamous names. Those who were told to forget misidentified more nonfamous names as famous than those who had been told to remember.
Such a judgment is of course made on the basis of the familiarity of the name. It is exposure to an item that affects its familiarity – not whether or not you consciously remember it. By telling the participants to “forget” what they’d seen, the experimenters were removing the participants’ awareness of the source of the familiarity, not the familiarity itself.
The study appeared in the Journal of Experimental Psychology: Learning, Memory, and Cognition. Full reference
http://www.apa.org/monitor/study.html