Page 89 - BBC - The Scientific Guide to a Healthier You

SLEEP

By carefully manipulating your sleep patterns you can

turn your snoozes into the ultimate cognitive enhancer

words by DR PENELOPE LEWIS

P eople do all kinds of things somehow improved their memories.

But it was only when we started to understand
to get ahead in today’s
competitive world. The struggle
the different phases of sleep (each characterised
for jobs and promotions
by a different depth of sleep and different
is cut-throat, and the use
of performance-enhancing
that we started to fully grasp exactly how
drugs such as Modafinil and Ritalin is patterns of electrical activity in our brain)
sleep affects memory. What became clear is
on the rise. But ironically, nature’s best that the different phases consolidate different
cognitive enhancer is often entirely overlooked. types of memory.
What makes you feel great when you have
it and a complete basket case when you miss MORE NONSENSE
out? That’s right: sleep. Something we should In 2013, researchers at the University of
all spend roughly one-third of our time doing, California conducted some research with
but which we actually tend to squeeze at echoes of that performed by Jenkins and
both ends, with under- Dallenbach almost 100
performance the result. years earlier, in that
But sleep is not only Need to memorise the participants were
critical for staying asked to learn nonsense.
alert and attentive. Spanish? Try an intense A bunch of young adults

We’re now beginning (whose average age was
study session in the
to understand the extent about 21) and a group
to which it influences of older adults (whose
our ability to learn new late afternoon, followed average age was about
things – everything 75) were instructed
from riding a bike to by a SWS-filled nap to learn word pairs
learning Spanish. And consisting of real words,
this is showing us how such as ‘birds’, and
made-up words, such as ‘jubu’. They found
we can use sleep to enhance our memories. were able to recall the pairings better the
that both the younger and older participants
The idea that sleep and memory are linked
PHOTOGRAPHY: STEVE SAYERS/THE SECRET STUDIO psychologists, John Jenkins and Karl Dallenbach at night.
is nothing new. Back in 1924, two American
more ‘slow-wave sleep’ (SWS) – characterised
at Cornell University, enlisted a pair of students
by a slow pulsing of brain activity – they had
to learn nonsense syllables. The researchers
Another piece of research that was perhaps a
then tested their memories one, two, four and
little more traumatic for its participants proved
eight hours later. What they found was that
that sleep also helps us remember events that
students could remember more of the syllables
fire our emotions. A group of students at the
when they had been to sleep between the
learning session and the test than when they
University of Bamberg in Germany were given
had been awake. In other words, sleep had
emotionally charged texts to read, such as one 5

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