Question

Passing through the NREM stages (1 through 4), the frequency of the EEG waves declines, but their amplitude increases. Passing through the NREM stages (1 through 4), the frequency of the EEG waves declines, but their amplitude increases. True or False?

Answer 1

Answer:

True.

Explanation:

Stage 1 of NREM sleep is characterized by a low amplitude EEG, mixed frequency between range a and s (2 to 7Hz). EMG activity is usually higher than at other stages of sleep, but amplitude can vary widely. Stage 2 of NREM sleep is recognized by background activity and episodes of sleep spindles and K-complexes. Sleep spindles are short (12 to 14 Hz) waves that increase and decrease in amplitude to produce a spindle characteristic.  Stage 3 NREM sleep is classified when slow waves or d waves (£ 2Hz) and high amplitude greater than 75mV (measured from lowest to highest wave - peak to peak) appear at 20 to 50% of the time of the day. record. Stage 4 NREM sleep is similar for EEG, EMG, and EOG from the previous stage; however, stage 4 is characterized by the presence of d waves in more than 50% of the time.

Accordingly, we can conclude that going through the NREM stages (1 to 4), the frequency of EEG waves decreases but their amplitude increases.