TechSmart 121, October 2013 TechSmart 132, September 2014 | Page 28

SCIENCE

Navigating Neverland

Making sense of dreams is almost as
nebulous as the dreams themselves. But it
seems science is slowly getting the hang
of navigating the twists and turns of the
sleeping mind. Linda Pretorius investigates.

The dream machine

Dreaming of doing

Last year, a team of scientists reported that they used brain scans of sleepers to
predict dream content. Study participants were woken up just as they started to
drift off and asked to describe what they were dreaming about. After about 200
recordings for each participant, the researchers compared the activity patterns
to those seen while the participants viewed similar images when awake. Then, by
looking at brain activity patterns as participants fell asleep again during the next
round, they predicted what images were likely being seen. Turns out they were
right about 60% of the time.

It seems our brains do the same thing in dreams as while awake. Lucid
dreamers were asked to dream about clenching their fists while brain scans were
recorded. Areas in the sensorimotor cortex, which is responsible for generating
the instructions that allow performing a movement, became highly active.
Scans taken when the subjects clenched their fists while awake showed the
same activation patterns. This suggests that our brains don’t just watch images
passively in our dreams, but actively participate in the actions we see.

1953: The start of dream research.

90 minutes: The average length of a complete sleep cycle.

Taking control

Stop the clock

Scientists think they might be one step closer to
understanding how we can take control of our dreams.
During a lucid dream, the prefrontal cortex becomes
quite active while in REM (Rapid Eye Movement)
sleep. This shows up as a specific 40 Hz wave on
an EEG. Scientists stimulated the prefrontal cortex of
sleeping volunteers with brief electrical pulses and
asked them to rate their awareness of dreaming after
each session. Subjects reported a marked
increase in being aware of dreaming
and controlling the storyline when
40 Hz pulses were used. The results
may be useful in treating mental
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