A case of brain short-circuit?

Bonita Baruah / Jan 6, 2007, 23:32 IST

Text Size

Small
Medium
Large

We all experience rage and some form of sexual abuse at some time or other, yet most of us don't cross over to the other side because we have a sort of 'internal cage' that keeps our inner monsters locked.

KILLER KINK
How are we different from psychopaths? We all experience rage and, psychoanalysts say, even some form of sexual abuse at some time or other, yet most of us don't cross over to the other side because we have a sort of 'internal cage' (social or moral conditioning) that keeps our inner monsters locked.
But brain malfunction when the wiring in the brain goes wrong may also cause violent aggression.
Here's what happens: The cerebrum consists of the neocortex and the limbic system the latter is the primitive or reptilian brain which has evolved over millions of years and controls our basic instincts like anger, fear, pain, anxiety, sexual instincts, etc.

The neocortex or new brain (which has developed more recently in evolutionary terms) is the thinking brain, or reason, which inhibits the primitive brain.
Both constantly talk and supply information to each other, but for various reasons the primitive brain sometimes refuses to take orders from the thinking brain: this is when things go awry.
"Many things can go wrong," says Srishti Nigam, pathologist & psychologist practising in Canada. "A combination of genetic make-up, life experiences and environmental influences (like trauma or war) shapes the brain.

But a lot of things can go wrong and the interplay between the two gets disrupted, and aggression and sexual desires go out of control." Alcohol, drugs and disease also influence the inhibitory effect of the cortex.
BLAME THE AMYGDALA
Charles Whitman, a sniper who killed several people in Texas, left a note behind that begged people to examine his brain for possible dysfunction. His autopsy revealed he had a tumour pressing into the amygdala.
The hypothalamus and pituitary gland are important parts of the brain's limbic system associated with emotional response and arousal; these, and the septum and amygdala, may play a role in aggression, according to research on the neurobiology of aggression.
THE CRIMINAL MIND
Adrian Raine, a psychologist at the University of California, LA, conducted the largest and most thorough study in which positron emission tomography (or a PET scan) was used to compare brain activity in 41 convicted violent offenders.
They were found to have reduced activity in the prefrontal cortex and increased activity in the subcortal regions like the thalamus.
Phineas Gage was the first patient from whom we learned something about the relationship between personality and the brain. Gage was foreman of a railway construction company when a tamping iron accidentally went through his head.
He survived, and some months later resumed work, but his personality had changed drastically: From a well-balanced, capable and shrewd guy, he had become fitful, impatient and grossly profane.

End of Article