AP PSYCHOLOGY

Detailed explanation-1: -Sleep spindles are short (<2 s), synchronous bursts of activity between 11 and 17 Hz. They are found throughout NREM sleep but are particularly numerous in NREM stage 2 (NREM2) sleep.

Detailed explanation-2: -Along with another wave pattern called K-complexes, sleep spindles are considered a hallmark of stage 2 NREM sleep.

Detailed explanation-3: -Sleep spindles are bursts of neural oscillatory activity that are generated by interplay of the thalamic reticular nucleus (TRN) and other thalamic nuclei during stage 2 NREM sleep in a frequency range of  11 to 16 Hz (usually 12–14 Hz) with a duration of 0.5 seconds or greater (usually 0.5–1.5 seconds).

Detailed explanation-4: -Stage 2. Stage 2 NREM sleep sees a continued slowing of heartbeat, breathing, muscle activity, and eye movements. During this stage, you also experience a reduction in body temperature. Throughout the course of the night, you spend about half the time in stage 2 sleep.

Detailed explanation-5: -Sleep spindles-bursts of 11–15 Hz (sigma frequency band) activity, typically between 0.5 and 2 s in duration-are characteristic transient features of the sleep electroencephalogram (EEG). Spindles are most prominent during N2 sleep and are in fact a defining feature of this stage.