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Sleep may consolidate bad feelings
By Laura Sanders
A night of shut-eye sears bad feelings
into the brain, while waking hours take
the emotional edge off, a ne w study finds.
Though preliminary and somewhat
inconsistent with earlier research, the
results suggest that staying awake after
something awful happens might be a way
to blunt the emotional fallout of trauma,
researchers report in the Jan. 18 Journal
of Neuroscience.
In the study, Rebecca Spencer of the
University of Massachusetts Amherst
and her colleagues showed pictures
of neutral scenes, such as a street, or
negative scenes, such as a car wreck,
to 106 young adults. Participants then
rated the emotion inspired by the image
on a one-to-nine scale ranging from sad
to happy. Afterward, participants either
went to bed for a night’s sleep or were
asked to stay awake for 12 hours. Then
the researchers retested the participants
by showing some of the same pictures
mixed in with new images.
Psychedelics
chill brain out
Magic mushrooms subdue
areas tied to self-awareness
By Devin Powell
When Timothy Leary advised his
generation to “turn on” by taking
psychedelic drugs, he got it all wrong.
Turning off parts of the brain may be
the real secret to expanding your mind,
research reported online January 23 in
the Proceedings of the National Academy
of Sciences concludes.
“The findings are astounding and
are going to completely change how we
understand the action of hallucinogens,”
says psychiatrist and pharmacologist
Bryan Roth of the University of North
Carolina at Chapel Hill.
A team led by psychiatrist and neuro-psychopharmacologist David Nutt of
Imperial College London recruited 15
people with previous experience taking
hallucinogens. Each was injected with a
small amount of psilocybin, the ingredient responsible for magic mushrooms’
mind-bending properties.
Before and after the volunteers
Psilocybin, the active ingredient in psyche- delic mushrooms, shuts down hubs link- ing different parts of the brain, as shown in functional MRI scans (lighter blue indicates less activity after taking psilocybin com- pared with a placebo).
tripped out, their brains were scanned.
These measurements revealed decreases
in blood flow through parts of the
volunteers’ brains. Surprised by the
result, the researchers repeated the
experiment with another group using a
different scanning technique. The same
pattern emerged, most pronounced in
the hubs that connect different parts of
the brain — including the thalamus and
parts of the cingulate cortex.
Studies in mice suggest that hallucinogens stimulate certain neurons in the
visual regions of the brain, which would
explain the kaleidoscopic hallucinations
users often experience.
But suppressing regions that coordinate and control the brain could have
deeper consequences.
“Decreasing the activity in certain
hubs in the network may allow for a
more unconstrained conscious experience,” says Matthew Johnson, an
experimental psychologist at Johns
Hopkins University School of Medicine
who studies psilocybin and other hallucinogens. “These drugs may lift the
filters that are at play in terms of limiting
our perception of reality.”
ROBIN CARHART-HARRIS, D. NUTT
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