01:146:245 Lecture Notes - Lecture 27: Circadian Rhythm, Frontal Lobe, Meninges

• School: Rutgers University
• Department: Cell Biology and Neuroscience
• Course: 01:146:245
• Professor: Professor Wilhelms

Document Summary

~sleep and waking are periodic behaviors to fit with oscillating environment of earth. ~circadian rhythm is daily cycle, calibrated visually by the sun. ~recording the collective activity of neurons from the scalp surface. ~volume conductance the current made by neurons flows through the extracellular space and is picked up by the eeg, summed current of 1000s of neurons. Alpha is 18-13 hz when you"re relaxed and awake, best done over parietal and occipital lobes. Beta is 13-30 hz lowest amplitude, most dissynchrony, intense activity in frontal lobe. Theta is 4-7 hz also high amplitudes, during sleep. ~the eeg signal needs to penetrate meninges, fluid, skull, skin. ~takes 1000s of neurons to generate a detectable signal. Btw cortex makes up 80% of the brain. At least one of the 6 layers of brain is made of pyramidal cells. The cells are oriented parallel to each other. Dendrites of pyramidal cells are perpendicular to brain surface.