During hibernation the ground squirrel has periodic arousals and normothermia. Mechanistically, what is happening during those periods, and why do you think they happen? Solution Hibernating mammal is conscious in the spring and summer its brain remains resilient to the sort of air deprivation and neuronal damage that frequently result from heart attacks and stroke. When little mammals first developed hibernation, their energy-hungry heads were put in an impossible condition: survive half the season with minimal air or nutrition and arise from the complete experience unscathed. Plainly, hibernation didn\'t destroy the brain—it just managed to get stronger. Environmental heat that does not trigger increased or frustrated task of body cells. Surface squirrels don\'t drop in body heat significantly throughout hibernation or do they enter periodic bouts of arousal. Rather, they stay in gentle continuous hibernation in every winter. Without sporadic arousals to clear hyperphosphorylated tau from their heads, hibernating squirrels tiptoe perilously shut to neurodegeneration, but somehow control to reverse the damage when they awaken in the spring..