Physiology Lab – EEG Questions And Answers

What does EEG activity show? correct answer: the summed ionic flow (current) of thousands or even millions of neurons that have similar spatial orientation (if not similar spatial orientation, won't line up and waves not created) Do EEG recordings only reflect the electrical activity of neurons directly under the scalp electrodes are placed? correct answer: NO; because voltage decreases over distance, those deep in brain are less contributory BUT multiple areas are generally active during a particular task and signals get smeared by meninges, csf and skull how are EEGs useful in medicine? correct answer: to determine level of consciousness to evaluate sleep disorders to assess brain conditions and disease such as trauma, coma, mental retardation, encephalitis, cognitive impairment, brain tumors and epileptic seizures amplitude measures? correct answer: size of wave frequency measures? correct answer: number of wave cycles/second EEG during sleep correct answer: EEG patterns during REM sleep similar to EEG pattern when people awake REM correct answer: Rapid Eye Movement; when person's eyes move back and forth repeatedly most dreaming occurs here body's skeleton muscle activity very relaxed - almost paralyzed except movement of eye how many stages of sleep? correct answer: 5 (5=REM) alpha waves correct answer: resting brain waves beta waves correct answer: peak during concentration, visual stimuli, mental alertness