AP PSYCHOLOGY

Detailed explanation-1: -Siffre (1975) found that the absence of external cues significantly altered his circadian rhythm: When he returned from an underground stay with no clocks or light, he believed the date to be a month earlier than it was.

Detailed explanation-2: -Siffre was the first to show that our body might have its own clock. Since then, chronobiology has become a hugely important field of research.

Detailed explanation-3: -a net average of all the neurons’ potentials. What do the EEG waves look like when brain activity is “desynchronized"? With each succeeding stage of sleep (from 1 to 4): slow, large-amplitude waves increase in number.