Why does insomnia worsen distress of unpleasant memories?

woman not being able to sleep



By Catharine Paddock PhD  


Fact checked by Jasmin Collier

For people with insomnia,
sleep does not reduce the shame of an embarrassing experience. For them, the
distress does not fade; in fact, it can get worse with recall.

This was one of the findings
of a new study from the Netherlands Institute for Neuroscience in Amsterdam.
The study also revealed how
brain differences between people with and without insomnia might explain it.
A new paper in the journal
Brain describes how, using MRI scans, the researchers examined brain activity
in people with and without insomnia.
The participants underwent the
scans as they relived embarrassing experiences from decades ago plus a recent
memory from just a week ago.
The scans showed that, when
the group without insomnia relived old embarrassing memories, the brain
circuits they activated were “markedly different” to those they
activated as they recalled more recent embarrassing memories.
However, when those with insomnia
recalled old embarrassing memories, the brain circuits they activated
overlapped with the circuits that were active when they relived new
embarrassing memories.
The overlaps occurred
particularly in the anterior cingulate cortex (ACC), which connects parts of
the brain involved with emotional and cognitive processing.
First study author Rick
Wassing says that in people with insomnia, sleep does not help alleviate
emotional distress. “In fact,” he adds, “their restless nights
can even make them feel worse.”

Insomnia and ‘karaoke-style’
study


According to figures from the
American Sleep Association, about 30% of adults in the United States report
experiencing “short-term issues” relating to insomnia, while 10%
report persistent insomnia.
Experiencing difficulty
falling asleep is not the only or the main symptom of insomnia.
Other symptoms — such as
moodiness, a lack of energy in the daytime, irritability, and struggling to
focus on work — may also occur.
The authors note in their
study paper that although the term insomnia suggests that the issues relate
only to sleep, a diagnosis requires other measures, too — including many that
relate to “daytime complaints” and “round-the-clock
disturbances.”
The results concerning the
recent embarrassing event formed part of an earlier study, in which the team
had examined emotional distress in people with and without insomnia as they
recalled performing a “karaoke-style” solo song.
The scientists had invited the
participants to sing, without musical accompaniment, while wearing headphones
that prevented them from hearing themselves. This made it difficult for them to
find the right pitch.
About a week later, just
before undergoing MRI scans, the participants — as well as some of the
researchers — listened to the solo singing recordings.
On the first playback, all of
the participants reported having feelings of shame and embarrassment. However,
after a night of sleep, those who slept well reported feeling much less
distressed.
Those with insomnia did not:
Their emotional distress was even more marked after a restless night.

Emotional circuits fail to
disengage


The new findings suggest that
the ACC, which helps regulate emotion, also has an important role in insomnia.
Previously, when looking for
causes of insomnia, scientists had tended to focus on the parts of the brain
that control sleep.
The study authors posit that
people with insomnia have genes in their ACC that do not activate correctly
during rapid eye movement sleep. This stops the brain from disengaging
emotional circuits from the memories of distant distressing events.
“Brain research now shows
that only good sleepers profit from sleep when it comes to shedding emotional
tension.”
-Rick Wassing




SOURCE: MEDICAL NEWS TODAY
Kayode Ojo
Kayode Emmanuel Ojo is the Co-Founder and Managing Director at SHEFFA Limited. He is presently studying Computer Science at the National Open University, Victoria Island, Lagos.