The Pentagon's mad-science division has a new way to deal with the 70,000+ troops diagnosed with traumatic brain injury: Freeze 'em.

Darpa, the military's far-out research arm, is looking for research projects that would create a "therapeutic hypothermia device" to prevent traumatic brain injuries from causing permanent molecular damage to the brain. The idea is based on successful studies that used cortical cooling to treat survivors of strokes and cardiac arrest. According to Darpa's solicitation, cooling down the brain after trauma can offer "dramatic neuroprotection" that will prevent long-term harm to cognition and motor skills.

So far, Darpa-funded studies suggest that traumatic brain injuries are caused by repeated exposure to blasts, specifically the "supersonic wave" of highly pressurized air they emit. Within a fraction of a second after impact, brain cells, tissues and blood vessels are stretched, torn and distorted. Over the hours, days and months that follow, altered brain processes create a snowball effect of damage – which is why symptoms often don't show up until troops come home.

Those secondary changes to the brain are responsible for the long-term physical and cognitive symptoms endured by TBI sufferers, and they're what Darpa wants to curb. But once the processes set in, around 90 minutes after impact, they're hard to reverse. That's why a quick dose of hypothermia might come in handy: a portable brain-cooling unit, deployed in the field, could "extend the golden hour of patient survivability and increase the chances for full recovery."

That is, if researchers can get the thermostat right. The right degree of cortical cooling has proven effective, but cortical hyperthermia can actually worsen cortical trauma. And no two brains are the same: Darpa's solicitation notes that the ideal cooling temperature will "differ across individuals and injury."

Darpa's asking for a prototype, complete with internal "temperature-calibration technology" to optimize cooling temp and avoid "rewarming [the brain] too quickly." And a portable brain freezer will be a boost for civilians too: Americans are about as likely to suffer a TBI as heart disease.

Photo: National Science Foundation

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