Hot and Bothered

People on trial for murder may claim that they committed their crimes"in the heat of the moment." Now, new research suggests that's more than a figure of speech.

People on trial for murder may claim that they committed their crimes"in the heat of the moment." Now, new research suggests that's more than a figure of speech.

Rates of serious and deadly assault rise along with the mercury, according to a study by Craig Anderson, Ph.D., even when factors like poverty level, demographics, and regional and cultural differences are accounted for.

That's because the same physiological pathways that allow our bodies to regulate internal temperature are also the routes along which emotions travel, explains the University of Missouri psychologist. When they're being used to cool the body, they may have less capacity to restrain combative urges.

Though we're all more irritable when we're hot, Anderson admits that murder may seem more of a stretch. He explains his results with what he calls an "escalation cycle," pointing out that arguments don't typically start with a major incident, but with a series of minor provocations.

On a comfortably cool day, the quibble might end there. On a hot day, however, "people are physiologically aroused because of the heat, and that arousal increases the likelihood that the quarrel will go to the next level," says Anderson. "That may be all it takes."

And all it may take to quell such violence, adds Anderson, is a little AC. He thinks that air conditioners installed in high-crime or potentially volatile areas, such as prisons, may help people keep their cool.

But he warns that air conditioners face growing competition from an overheated environment: He estimates that over the next few decades, global warming may increase the serious and deadly assault rate by about 115,000 attacks each year.

PHOTO (COLOR): Hot and Bothered