PSYCH 110 Lecture Notes - Lecture 19: Memory Consolidation, Brainstem, Thalamus
Document Summary
Sleep - having a higher threshold for sensory input (harder to wake someone up with. Lecture #19: sleep (03/21) lights or sound, etc. ) Most mammals sleep (range from like 2 hours to 20 hours per day) Dolphins sleep one hemisphere at a time. Electroencephalogram (eeg) measures summed electrical activity from any cortical neurons. Electrodes stuck on the head (doesn"t penetrate the skin), recording extracellular electrical activity in the cortex. Beta waves - when you are awake, not synchronous, low amplitude. Delta waves - higher amplitude, lower frequency, slow wave sleep, neurons firing ap at the same time, in sync. Eeg during the four stages of non-rem sleep five stages: 1, 2, 3, 4 and rem (rapid eye movement) sleep. These stages progress cyclically from 1 through rem then begin again with stage 1. A complete sleep cycle takes an average of 90 to 110 minutes. Right before start to fall asleep, beta alpha waves (eyes droopy), synchronized brain activity.