In
the Guardian this year, there was a long and very fascinating article
entitled “Total Recall: The People Who Never Forget.” The
article discusses very rare cases of people with what what is called
hyperthymesia or Highly Superior Autobiographical Memory, a topic
that the 60 Minutes
TV program had covered in 2010.
Less
than 100 such people have been identified. They have the uncanny
ability to remember in great detail every single day of past years of their lives, sometimes stretching back for decades.
The
article discusses Jill Price, and says this about her:
Price
was the first person ever to be diagnosed with
what is now known as highly superior autobiographical memory, or
HSAM, a condition she shares with around 60 other known people. She
can remember most of the days of her life as clearly as the rest of
us remember the recent past, with a mixture of broad strokes and
sharp detail. Now 51, Price remembers the day of the week for every
date since 1980; she remembers what she was doing, who she was with,
where she was on each of these days. She can actively recall a memory
of 20 years ago as easily as a memory of two days ago, but her
memories are also triggered involuntarily.
A memory researcher
named James McGaugh has verified the accuracy of Price's
recollections. One way to do this is simply to ask her questions
about what happened on a particular day that something notable
happened. For example, if asked on what day Rodney King was beaten,
or what day Bing Crosby died, she can quickly recall the exact date.
Of if asked the significance of some particular date, she can tell
you some famous person died on that day. McGaugh also verified the
accuracy of Price's recollections by checking her diary. He and his
colleagues wrote up the case in a scientific paper.
Another scientific
paper (which can be read in full here) describes the case of HK,
which the 2012 paper describes as a 20-year old person with “near-perfect”
autobiographic memory. HK is described as blind and having been born
at 27 weeks early, 13 weeks early. The paper states:
As
can be seen in Figure 1,for dates between this first memory until his 10th
year of life, HK shows a relatively steady increase in accuracy for
autobiographical events. Accuracy takes a noticeable jump to near
90% in 2001 at age 11. From that point forward, HK’s recollection
of autobiographical events is near perfect.
The paper also gives
us insight as to what it is like to have such a memory:
He
reports that he is able to relive memories in his mind as if
they just happened. HK stated that everything about his memory,
including sounds, smells, and emotions, are vividly re-experienced
when he remembers a particular event in time...,He stated that there
is no difference in the vividness of his recollection between events
that occurred when he was five and events that he experienced within
the past month.
The
scientists did an MRI scan of the brain of this person with this
near-flawless autobiographic memory. Did it show something like an
abnormally big brain? No, something like the opposite was found. For
the paper tells us that the volumetric analysis “reveals
significantly reduced total tissue volume in HK” and that “a
volumetric analysis of subcortical structures shows
general reduction in subcortical volumes in HK (1019 mL) relative to
controls (1249 ± 29 mL).” So the person with this miracle memory
had a brain about 20% smaller. The only part of his brain that was
larger was his amygdala, an almond-shaped part of the brain. HK's was
20% bigger, but that's only a flea-sized difference.
Cases
such as Price and HK apparently date back to the nineteenth century,
for an 1871 article describes a man named Daniel McCartney who,
according to the Guardian article, “could remember
the day of the week, the weather, what he was doing, and where he was
for any date back to 1 January 1827, when he was nine years and four
months old.”
Something
different from these cases of Highly Superior Autobiographic Memory
or hyperthymesia are the cases of extraordinary memory in savants.
Savants
are individuals who have some mental disability but also have some
extraordinary mental talents. An example of a savant is the late Kim
Peek, who could accurately recall the details of 12,000 books he
had read, despite having an IQ of only 87. Other examples are Tony
DeBlois, who can play 8000 songs from memory, and Derek Paravicini
who can play a piece after hearing it only once, despite having a severe learning disability.
So far researchers
have failed to draw any noteworthy conclusions from these cases of
extraordinary memory. But such cases may suggest that standard ideas about memory are wrong. The standard story
is that memories are all stored in your brain. There are several
reasons for rejecting this idea, such as the seeming impossibility of explaining how instantaneous recall of distant memories could occur (discussed here), and the reason (discussed here) that there is no
workable theory of how brains could be storing memories for 50 years.
The most popular theory is that memories are stored in synapses. But
synapses are subject to a high rate of protein turnover and
structural turnover which should make it impossible for synapses to
be storing memories for longer than a year or two. The proteins in
synapses are replaced within a few weeks. A recent scientific paper mentions an estimate that the rate of protein turnover in synapses is about 0.7% per hour, which is a rate of about 16% per day.
Under the assumption
that memories are stored in brains, we would not by any means expect
some people to remember their past experiences 800% better than an
ordinary person can. Such a thing would seem to require a brain 800%
bigger than the biggest brain that can fit into a human skull. And
also under the assumption that memories are all stored in brains, we
should not expect people with smaller brains or damaged brains (such
as patient HK and Kim Peek) to have dramatically better memories.
But let's imagine a
different scenario. Imagine if people's memories are not stored in
brains, but are stored in some psychic or spiritual reality
associated with a person. Your memories may be stored in something
like your soul, not your brain. Under such a scenario, you might have
complete memories for everything that happened to you. But your brain
might act as a kind of valve, limiting your access to these memories.
For some rare people, this normal blockage or limitation of access to
biographical memory may not be occurring. Such people may have
Highly Superior Autobiographic Memory.
Cases of Highly
Superior Autobiographic Memory are easy to reconcile with such a
theory. We simply imagine that in such people the brain's function as
a kind of “blockage valve” for our memories is not working
normally, so the blockage does not occur as it normally does. But
cases of Highly Superior Autobiographic Memory are hard to reconcile
with standard claims that the brain is where all your memories are stored. Under such claims, it is unthinkable that anyone should
have memories such as Jill Price's, which would seem to require a
brain the size of an elephant's.
Postscript: Another interesting mind anomaly is the rare anomaly of acquired savants. A person may acquire extraordinary mental abilities after some accident. One such case is Orlando Serrell, who acquired extraordinary calculation and memory skills after being hit by a baseball when he was 10, in 1979. According to his web site, "He can recall the weather, where he was, and what he was doing for every day since the accident." Again, we have something that does not fit in with conventional dogmas about the brain, but which is compatible with very different ideas about memory. If your brain acts as a kind of faucet or valve for your memories, rather than a storehouse of such memories, it might be that a head injury might reset that valve so that memory is dramatically enhanced.
Postscript: Another interesting mind anomaly is the rare anomaly of acquired savants. A person may acquire extraordinary mental abilities after some accident. One such case is Orlando Serrell, who acquired extraordinary calculation and memory skills after being hit by a baseball when he was 10, in 1979. According to his web site, "He can recall the weather, where he was, and what he was doing for every day since the accident." Again, we have something that does not fit in with conventional dogmas about the brain, but which is compatible with very different ideas about memory. If your brain acts as a kind of faucet or valve for your memories, rather than a storehouse of such memories, it might be that a head injury might reset that valve so that memory is dramatically enhanced.
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