“Why we are the way we are: the Internet of our brains. These are axonal nerve fibers in the real brain as determined by the measured anisotropy (directionality) of water molecules inside them. 3T 30 channel GRAPPA DTI scan protocol, deterministic tractography performed using TrackVis/FACT algorithm. You might know the subject :-)”
jgmarcelino from Newcastle upon Tyne, UK
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Disaster Survivors: How Stress Changes the Brain
How well a person recovers from traumatic events may depend in part on their self-esteem, according to researchers who examined the effects of a major earthquake on the survivors’ brains.
The researchers had conducted brain scans of university students for a study before the Great East Japan Earthquake struck in 2011. After the earthquake, they repeated the scans on 37 of the same people, and tracked stress-induced changes in their brains in the following months.
“Most importantly, what these findings show, is that the brain is dynamic — that it’s responding to things that are going on in our environment, or things that are part of our personality,” said Rajita Sinha, professor of psychiatry at Yale School of Medicine, who wasn’t involved in the study. [Top 10 Mysteries of the Mind]
In the brain scans taken immediately after the incident, the researchers found a decrease in the volume of two brain regions, the hippocampus and orbitofrontal cortex, compared with the scans taken before the incident.
One year later, the researchers repeated the scans and found that the hippocampus continued to shrink, and people’s levels of depression and anxiety had not improved.
TUESDAY, April 29, 2014 (HealthDay News) — A small study of people who experienced the devastating 2011 earthquake in Japan shows that although traumatic events can shrink parts of the brain, some of those regions can rebound once a person’s self-esteem returns.
“Higher self-esteem is one of the most important traits of resilience in the context of stressful life events,” said study author Atsushi Sekiguchi, who noted that these latest findings also illustrate that brain changes are dynamic and fluid over time.
Sekiguchi’s prior research had already demonstrated that people with lower self-esteem following a traumatic event are likely to experience a quick, short-term drop in the size of their orbitofrontal cortex and hippocampus. The first brain region is involved in decision-making and emotions, while the second area is involved in memory.
But by tracking the same individuals over time, Sekiguchi’s team observed that the “part of the brain volume which had decreased soon after a stressful life event [ultimately] increased, especially in individuals with [renewed] high self-esteem.”
Sekiguchi, from the division of medical neuroimage analysis at Tohoku University in Sendai, Japan, and his team report the findings in the April 29 online edition of Molecular Psychiatry.
To gain insight into how the 2011 earthquake — and ensuing tsunami that heavily damaged several nuclear reactors in northern Japan — affected its victims, the researchers focused on 37 men and women who were about 21 at the time.
All had MRI brain scans right after the earthquake, and then again one year later.
At the same time, the earthquake victims were given psychological assessments to gauge anxiety, depression, low self-esteem and other characteristics of post-traumatic stress disorder (PTSD).
Investigators concluded that none of the patients ever developed full-blown PTSD.
Yet, the group did experience a big dip in self-esteem immediately following the earthquake. And by comparing their brain scans with those of 11 other people taken before the earthquake, the team determined that the loss of self-esteem was accompanied by a downsizing of the brain’s orbitofrontal cortex.