When your memories can no longer be trusted

You went to a wedding yesterday. The service was beautiful, the food
and drink
flowed and there was dancing all night. But people tell you that you
are in
hospital, that you have been in hospital for weeks, and that you
didn't go to a
wedding yesterday at all.

The experience of false memories like this following neurological
damage is
known as confabulation. The reasons why patients experience false
memories such
as these has largely remained a mystery. Now a new study conducted by
Dr Martha
Turner and colleagues at University College London, published in the
May 2008
issue of Cortex offers some clues as to what might be going on.

The authors studied 50 patients who had damage to different parts of
the brain,
and found that those who confabulated all shared damage to the
inferior medial
prefrontal cortex, a region in the centre of the front part of the
brain just
behind the eyes.

"The patients who confabulated had varying levels of memory ability,
and varying
levels of "executive functioning" (the set of cognitive abilities
overseen by
the prefrontal cortex that control and regulate other abilities and
behaviours),
so confabulation cannot be as simple as a combination of these
deficits. Instead
it must be due to a specific function controlled by the inferior
medial
prefrontal cortex. Damage to this region appears to lead to the
convincing
experience of false memories" says Martha Turner, corresponding author
for this
study.

This study has implications for our understanding of how the human
brain
controls memory, and how most of us are able to easily tell apart true
memories
from things we have imagined, dreamed or invented.

Source: Elsevier
http://www.physorg.com/news131185824.html