As the name implies, cold therapy is done by subjecting the patient to cold temperatures, creating a physiological response in the body and subsequently the brain. A study at the Virginia Commonwealth University School of Medicine established that depressed patients who were treated with cold showers showed a significant improvement in mood.

The treatments consisted of cold showers that were 20°C for 2 to 3 minutes, performed once or twice daily over several months. The evidence suggested that exposure to cold activates the sympathetic nervous system, increases the blood level of beta-endorphin and noradrenaline, and increases synaptic release of noradrenaline in the brain. Additionally, due to the high density of cold receptors in the skin, the cold shower sent electrical impulses from peripheral nerve endings to the brain, which resulted in the anti-depressive effect.

Cold therapy helps with depression by creating the same type of physiological stressors that have been experienced by primates through millions of years of evolution, such as brief changes in body temperature produced by a cold swim. It’s theorized that lack of this type of thermal exercise may impede adequate functioning of the brain.

As the temperature of a human body drops below the level required for health, various reactions occur to protect the core--that is, the abdominal organs and brain--from damage, even at the expense of the extremities. The brain is literally insulated against extreme cold, and it will begin to suffer symptoms of damage only at the point of advanced hypothermia, long after muscular symptoms such as shivering first appear. This assumes that the core temperature is not dropping very rapidly, as when a person is submerged in cold water

The average healthy temperature of a human body is 36.1 to 37.5° C, or 96.9 to 99.5° F. Hypothermia is defined as any temperature below 35° C or 96° F. This is the beginning of stage 1 hypothermia. Brain function becomes noticeably impaired only during stage 2, which begins at around 33°C or 93°F. The person may exhibit confusion. Many of the symptoms which may appear potentially neurological, including lack of coordination, stumbling and labored speech, are in fact muscular in nature. As part of the body's effort to protect the internal organs, the vasomotor response constricts blood vessels in and near the skin. Consequently, the hands, face and legs lose function, although the brain is largely unaffected.

Temperature jolts to brain may have a similar effect as the phenomenon of homeopathy, whereby small doses of something harmful may actually promote healing by stimulating the body’s repair and recovery systems. Electric shock and deep brain stimulation treatments operate on a somewhat similar principal, only with frightening potential side effects, such as memory loss and cognitive impairment.

References
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