AP Psychology Practice Test 2025 – 400 Free Practice Questions to Pass the Exam

Sleep spindles are defined as bursts of rapid, rhythmic brainwave activity that occur during non-REM sleep, specifically in stage 2 sleep. These spindles are characterized by a frequency of about 12 to 16 Hz and are identified through an electroencephalogram (EEG). They are believed to play a role in various sleep functions, including memory consolidation, learning processes, and the processing of information gathered while awake.

This choice accurately describes the nature and function of sleep spindles, contrasting with the other options provided. The first option discussing a sequence of thoughts in a sleeping person's mind does not pertain to the physiological aspect of sleep spindles. The third option refers to sleep apnea, a condition involving interruptions in breathing rather than an EEG phenomenon. The fourth option describes hallucinations, which are unrelated to the specific brainwave activity associated with sleep spindles. Thus, recognizing sleep spindles as bursts of brainwave activity captures their essential characteristics in the context of sleep research.