Case reports of accidental hypothermia followed by circulatory arrest with excellent recovery has inspired the implementation of hypothermia as a therapy to protect the brain from anoxic or traumatic injury. However, surprisingly little is known about the effect of neuronal cooling per se. The critical factors leading to successful cooling and rewarming has yet to be determined.There is at present few (or none) standard measurements in human patients that can provide predictions of the outcome after a hypothermic event. Critical factors for neuronal survival and long term effects on brain function after hypothermia and rewarming still remain elusive. In this pilot project we want to develop a rat model for cooling and rewarming, with quantification of neurologic and cognitive outcome and final neural damage in the hippocampus.