Tag Archives: stress

Pupil-dilation stress-scanner: You’re walking through an airport…you come across a tortoise…

pkdThe Guardian reports that the U.S. government is looking for a way to spot evildoers by scanning for “physiological abnormalities.” A call for proposals says:

Early research has shown that pupil size varies with changes in a person’s cognitive processing load. Current but unproven studies suggest that a cognitive decision to deceive or practise deception will result in an increased pupil size due to the greater cognitive processing required in comparison to truthful recall.

Sounds more than a bit like the Voight-Kampff replicant-detector test from Blade Runner (it was Philip K. Dick’s idea, Guardian, not Ridley Scott’s). The reporter adds an appropriate note of skepticism:

I wonder how often a system might raise a false alarm, since a lot of people are pretty stressed going through airports even when they’re not up to anything mischievous.

[Image: Torley]

Stress physically reshapes the brain

A neuroscience conference in Washington, D.C. this week could stress you out all by itself. Lab rats put in stressful situations — like being immobilized and forced to listen to loud rock music — grow fewer fibers that connect neurons. Stress isn’t that great for people, either.

“Stress causes neurons (brain cells) to shrink or grow,” said Bruce McEwen, a neuroscientist at Rockefeller University in New York. “The wear and tear on the body from lots of stress changes the nervous system.”

He said that stress is “particularly worrying in the developing brain, which appears to be programmed by early stressful experience.”

Stress in early life, even in the womb, can later lead to undesirable changes in behavior and the ability to learn and remember. Other consequences may be substance abuse and psychiatric disorders, researchers said…

“Pre-natal stress can change the brain forever,” said Tallie Baram, a neurologist at the University of California, Irvine. “Stress changes how genes are expressed throughout life.”

[1899 drawing of pigeon neurons by Santiago Ramón y Cajal, Wikimedia Commons]

Are antisocial kids just cortisol deficient?

Research at Cambridge University has found a link between delinquent behaviour in children and reduced levels of the so-called stress hormone, cortisol, which “enhances memory formation and is thought to make people behave more cautiously and to help them regulate their emotions, particularly their temper and violent impulses.”

First of all, I find this a little worrying, as it seems to be part of a trend to reduce all psychiatric problems (especially in kids) to phenomena that can be regulated with the correct cocktail of chemicals. Secondly, assuming for a moment that the link is confirmed, is this a recent development? In other words, have low-cortisol brains evolved as a response to an increasingly stressful world, or is the cause environmental?

And thirdly, has anyone thought of doing cortisol level testing on politicians? [story via FuturePundit]