Whether you're on a long-anticipated vacation
or a dreaded business trip, that first night
in a new environment tends to result in some
rather crappy sleep. Now a new study published
in Current Biology uncovers what's actually
happening in the brain
during that uneasy slumber.
A team of Brown University researchers set
out to investigate the "first-night effect"
by pointing a whole array of brain-monitoring
devices at 35 volunteers during two nights
of slumber. They discovered the brain essentially
sleeps with one eye open during that first
night, like Rambo clutching a knife, ready to wake and go all stabby
should any bad guys show up. Specifically, the
default-mode network of the brain's left hemisphere
remains more active during the first night's
slow-wave phase. We're talking a network of
brain regions concerned with introspective,
egoic chatter about the past and future --- the
worrisome, depressive, teeth-gnashing voice
humans seek to silence through everything
from exercise and meditation to psychedelic
drug use and various flow-state hobbies. THAT's
the voice that won't quite shut up during
that first night in a strange and uncertain
bedroom. The volunteers didn't report any
unusual discomfort or anxiety, however. They
didn't conduct the experiment in a haunted
house or anything. Rather, this increased
activity just seems to be business as usual
for the sleeping brain in a new locale. The
researchers believe these findings to be the
first of their kind, so many questions remain.
They only looked at four networks in the brain,
so they're not sure if the left hemisphere
is the lone watchman, or if it swaps out duties
with the right. And if so, why does the default-mode
network pull first watch? Of course, humans
aren’t the only animals to "sleep with one
eye open." Marine mammals, especially, demonstrate
what's known as Unihemispheric slow-wave sleep,
effectively resting the brain halves in shifts
so they're always awake enough to surface and breathe.
So sleep on that. And if you crave more scientific
insight into this weird world of ours, be
sure to visit now.howstuffworks.com each and
every day.
