Persistence of EEG activity with prolonged induced hyperthermic fever

Ten instances of deliberate systemic temperature elevation in the 41.5 degrees C to 42.2 degrees C range have been evaluated electroencephalographically, demonstrating decrease in predominant frequency and voltage. Persistence of electro-cerebral activity suggests that previous reports of electro-cerebral inactivity with elevated temperatures reflect indirect serious effects due to cardiovascular compromise with cerebral ischemia, rather than to a direct temperature-related loss of CNS electrical activity.