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SLEEP

5 The combined therapy effectively returned well during the day, despite the sleeping
the insomniacs’ performances on the tasks to difficulties.”
normal levels. Those who received it became Dr Altena’s group has found that insomniacs’
significantly slower on the simple task and brains are structurally different to those of
faster on the complex task when tested later. good sleepers. They used a brain-scanning

This outcome suggests that an insomniac’s brain technique called voxel-based morphometry to
works differently to others and that some of the measure and compare the volumes of various
cognitive changes associated with insomnia brain structures in 24 chronic insomniacs and
are at least partly reversible. 13 healthy control subjects. The insomniacs
In another study, Dr showed reduced volume of
Altena and her colleagues “Insomniacs grey matter in three regions
found that insomniacs of their brains. Plus, the
outperform good sleepers suffer from a reduced volume of the orbito-
on a verbal fluency task. frontal cortex was strongly
Test subjects had to press condition that’s related to the severity of the
a button whenever a word insomnia – the more severe
belonging to a specified best described a volunteer’s complaints, the
category was presented. greater the volume reduction.
The performances of the as a light form The results fit well with the
insomniacs who received functions of the orbito-frontal
sleep therapy for six weeks of stress” cortex, which is known to be
was comparable to that of involved in decision-making
Scientific studies are trying
the healthy control subjects and problem-solving, both to get to the bottom of
when they were tested again. of which are significantly impaired following what makes for a good
night’s sleep
“Insomniacs suffer from a physiological sleep deprivation. But it’s unclear whether
condition best described as a light form of these structural changes cause the insomnia
stress, which can be measured in higher or come after it.
brain activation when trying to fall asleep,” “To draw conclusions about the neural
Dr Altena explains. “This hyper-arousal may mechanisms underlying insomnia we need
underlie some of the high-performance levels to investigate which of these effects contribute

we observed. It may serve as a compensatory to the condition and which are consequences
mechanism of the brain to function relatively of it,” says Dr Altena.

SLEEP AND MEMORY

Don’t forget: beauty sleep is crucial

Quintilian, a famous first-century occur during short-wave sleep are
Roman teacher of rhetoric, noted the thought to mark the integration of
“curious fact that the interval of a new information with pre-existing
single night will greatly increase the knowledge. Also, changes in the
strength of memory”. And it’s now pattern of how genes are switched
well established that sleep enhances on or off during REM sleep may
memory consolidation. promote the strengthening of
Researchers from the University neuronal connectivity that is thought
of Haifa in Jordan have shown that a to underlie memory formation.
daytime nap enhances memory One study found that sleep
recall, and that even a short nap deprivation promotes the generation
lasting just six minutes is sufficient of false memories. So using it as a
to aid the processing of memories. technique when interrogating
The slow brainwave oscillations that suspects seems fairly pointless.

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