| Many
of us have experienced déjà
vu - the unsettling sensation of knowing
that a situation could not have been
experienced, combined with the feeling
that it has. It is usually so fleeting
that psychologists have until recently
thought it impossible to study. But
for some people, the feeling of having
been there before is a persistent sensation,
making every day a ‘Groundhog
Day’. Psychologists from Leeds’
memory group are working with sufferers
of chronic déjà vu on
the world’s first study of the
condition.
Dr Chris Moulin first
encountered chronic déjà
vu sufferers at a memory clinic. “We
had a peculiar referral from a man who
said there was no point visiting the
clinic because he’d already been
there, although this would have been
impossible.” The patient not only
genuinely believed he had met Dr Moulin
before, he gave specific details about
the times and places of these ‘remembered’
meetings.
Déjà vu
has developed to such an extent that
he had stopped watching TV - even the
news - because it seemed to be a repeat,
and even believed he could hear the
same bird singing the same song in the
same tree every time he went out. Chronic
déjà vu sufferers are
not only overwhelmed by a sense of familiarity
for new experiences, they can provide
plausible and complex justifications
to support this. “When this particular
patient’s wife asked what was
going to happen next on a TV programme
he’d claimed to have already seen,
he said ‘how should I know? I
have a memory problem!’”
Dr Moulin said.
For the first time, those
who suffer chronic déjà
vu can help provide sustained research
into the problem. “So far we’ve
completed the natural history side of
this condition - we’ve found ways
of testing for it and the right clinical
questions to ask. The next step is obviously
to find ways to reduce the problem,”
he said.
PhD
student Akira O’Connor, funded
by the Economic and Social Research
Council, is working with Dr Moulin to
find ways of creating the phenomenon
in the laboratory. Akira has begun inducing
déjà vu in Leeds students
using hypnosis, asking students to remember
words, hypnotising them to forget and
then showing them the same word again
to induce a feeling that they’ve
seen it before. The students are then
asked to make subjective reports - how
déjà vu actually feels
- in addition to the data about what
they can and cannot remember.
This new programme of
research, the Cognitive Feelings Framework
(CFF), is unique to the University,
and is being conducted by Dr Moulin
with ESRC professorial fellow Martin
Conway. “By considering subjective
experience - feelings - from a cognitive
science perspective, we hope to better
understand everyday sensations like
déjà vu, and also to help
understand cognitive impairment, for
example in older adults,” said
Dr Moulin.
“People might suffer
from chronic déjà vu,
but be unwilling to discuss this with
their doctor - any hint of ‘mental
illness’ is, particularly to older
people, a taboo subject. But as soon
as we found this first patient, we discovered
that if you ask the right questions,
you find other people have experienced
the same thing.”
Chronic déjà
vu can be distressing to the point of
causing depression, and some sufferers
have been prescribed anti-psychotics.
But Dr Moulin’s group believe
it is not a delusion, but a dysfunction
of memory: “The challenge is to
think about what this means. We can
use it to examine the relationships
between memory and consciousness.
“The exciting thing
about these people is that they can
‘recall’ specific details
about an event or meeting that never
actually occurred. It suggests that
the sensations associated with remembering
are separate to the contents of memory,
that there are two different systems
in the brain at work.” Dr Moulin
believes a circuit in our temporal lobe
fires up when we recall the past, creating
the experience of remembering but also
a ‘recollective experience’
– the sense of the self in the
past. In a person with chronic déjà
vu this circuit is either overactive
or permanently switched on, creating
memories where none exist. When novel
events are processed, they are accompanied
by a strong feeling of remembering.
A new collaboration launching
this month with the University of York’s
neuro-imaging lab will provide objective
evidence to the subjective reports supplied
by the CFF. “When examining someone’s
subjective experience, it’s important
to have an idea of whether their subjective
account is comparable to other people’s,”
said Dr Moulin. “The neuro-imaging
facilities allow us to see if the same
areas of brain are activated in different
people when they report certain subjective
states. Ultimately, we may even be able
to pinpoint the neural areas important
for conscious states such as remembering.”
Dr Moulin is keen to develop
a network of patients in Leeds and across
the globe who experience chronic déjà
vu. “We’re finding people
all over the world with these problems.
Chronic déjà vu sufferers
need the reassurance that they’re
not alone, and we need them to help
us learn more about who has it, what
causes it, and why.”
For more information on
Dr Moulin’s work see http://elgg.leeds.ac.uk/psccjam/weblog/
Photo 1: Déjà
vu revisited - Dr Chris Moulin believes
the problems lie in the temporal lobe
Photo 2: Hypnotised
- Akira O’Connor (right) is recreating
déjà vu in the lab
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