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Ice baths tamed his anger at horns
Learning the ice bath
Ralph Adolphs, a neuroscientist at Caltech, started ice baths years ago, back when they were not yet popular. The first week was terrible, a whole-body cold pressure task. By the second week his breathing and heart rate still rose, but gradually and with some automaticity. Eventually his heart rate and breathing dropped the moment he got in, and he felt super relaxed.
Calm at the horn
The effect spread beyond the tub. Driving around Pasadena, he had been trying to park on the street with his signal out, a space clear, and a lane open for the car behind him to move over. Instead the driver came right up behind him and went on the horn, which used to produce an immediate anger response. After the ice baths, the reaction was flat.
The response was an automatic down-regulation of his autonomic reaction to a psychological stressor, trained in the ice bath and generalized from it. It is an experiment of one, not a published study. The idea is that the strength and automaticity of control can be trained, so emotions get regulated without overthinking, smooth and effortless to some extent.
Why does repeated cold exposure change the body's response?
Sudden cold water triggers the cold shock response: a gasp, rapid breathing, and a surge in heart rate driven by the autonomic nervous system. Researchers led by Michael Tipton at the University of Portsmouth have shown that this response shrinks after only a handful of short immersions. The effect is a form of habituation, and in their studies it persisted for months. The adaptation involves the brain's regulation of the reflex rather than any change in the skin.
What slows the heart after a shock?
The autonomic nervous system has two arms with opposite effects on the heart. The sympathetic arm speeds it up, and the parasympathetic arm slows it down through the vagus nerve. At rest the vagus nerve holds the heart rate below its natural pacemaker rhythm of roughly one hundred beats per minute. The vagus is the tenth cranial nerve and runs from the brainstem down to the abdomen.
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