Eidetic memory is an ability to recall images, sounds or objects in memory with high precision
for a few minutes without using mnemonics.
It occurs in a small number of children and is virtually non-existent in adults.
The word eidetic comes from the Greek word εἶδος.
Overview Eidetic memory is the ability to recall images
in great detail for several minutes.
It is found in early childhood and is unconnected with the person's intelligence level.
Like other memories, they are often subject to unintended alterations.
The ability usually begins to fade after the age of six years, perhaps as growing verbal
skills alter the memory process.
Eidetic images are only available to a small percentage of children 6–12 years old, and
are virtually nonexistent in adults.
However, extensive research has failed to demonstrate consistent correlates between
the presence of eidetic imagery and any cognitive, intellectual, neurological, or emotional measure.
The popular culture concept of "photographic memory", where someone can briefly look at
a page of text and then recite it perfectly from memory, is not the same as seeing eidetic
images, and photographic memory has never been demonstrated to exist.
A few adults have had phenomenal memories, but their abilities are also unconnected with
their intelligence levels and tend to be highly specialized.
In extreme cases, like those of Solomon Shereshevsky and Kim Peek, memory skills can reportedly
hinder social skills.
Shereshevsky was a trained mnemonist, not a photographic memorizer, and there are no
studies that confirm whether Kim Peek had true photographic memory.
Persons identified as having a condition known as Hyperthymesia are able to remember very
intricate details of their own personal life, but this ability seems not to extend to other,
non-autobiographical information.
People with hyperthymesia have vivid recollections of such minutiae as what shoes a stranger
wore or what they ate and how they felt on a specific date many years in the past.
In cases where HSAM has been identified and studied, patients under study may show significantly
different patterns of MRI brain activity from other individuals, or even have differences
in physical brain structure.
Possibly because of these extraordinary abilities, certain individuals have difficulties in social
interactions with others who have normal memories, and may additionally suffer from depression
stemming from the inability to forget unpleasant memories and experiences from the past.
It has also been proposed that HSAM can be explained as a result of obsessive-compulsive
thoughts about memories rather than "photographic memory".
Skeptical views on photographic memory The American cognitive scientist Marvin Minsky,
in his book The Society of Mind, considered reports of photographic memory to be an "unfounded
myth".
An example of extraordinary memory abilities being ascribed to photographic memory comes
from the popular interpretations of Adriaan de Groot's classic experiments into the ability
of chess Grandmasters to memorize complex positions of chess pieces on a chess board.
Initially it was found that these experts could recall surprising amounts of information,
far more than non-experts, suggesting eidetic skills.
However, when the experts were presented with arrangements of chess pieces that could never
occur in a game, their recall was no better than the non-experts, suggesting that they
had developed an ability to organize certain types of information, rather than possessing
innate eidetic ability.
Scientific skepticism about the existence of photographic memory was fueled around 1970
by Charles Stromeyer who studied his future wife Elizabeth, who claimed that she could
recall poetry written in a foreign language that she did not understand years after she
had first seen the poem.
She also could, apparently, recall random dot patterns with such fidelity as to combine
two patterns into a stereoscopic image.
She remains the only person documented to have passed such a test.
However, the methodology of the testing procedures used is questionable as is the fact that the
researcher married his subject, and that the tests have never been repeated raises further
concerns.
Notable claims
With the questionable exception of Elizabeth, as of 2008, an article claims that of the
people rigorously scientifically tested, no one claiming to have long-term eidetic memory
has proven this ability.
There are a number of individuals with extraordinary memory who have been labeled eidetic, but
many use mnemonics and other, non-eidetic memory enhancing exercises.
Others have not been thoroughly tested.
See also Ayumu - a chimpanzee whose performance in
short-term memory tests is higher than university students
Exceptional memory – scientific background to the research into exceptional memory
Funes the Memorious short story discussing the consequences of eidetic memory
Hyperthymesia – a condition characterised by superior autobiographical memory
Synaptic plasticity - ability of the strength of a synapse to change
References