What type of waveforms are typical in NREM sleep?

In NREM sleep, the predominant waveforms observed are theta and delta waves. During the early stages of NREM sleep, particularly in Stage 1 and Stage 2, theta waves (which have a frequency of 4-7 Hz) are commonly identified. As the individual transitions into deeper stages of NREM sleep, particularly Stage 3 (also referred to as slow-wave sleep or deep sleep), delta waves become more prominent. Delta waves are characterized by their low frequency (0.5-4 Hz) and high amplitude, indicating a deeper state of sleep and reduced brain activity, which aligns with the restorative functions of this stage.

Alpha and beta waves are typically associated with wakefulness and active mental states. Gamma waves are linked to processes involving higher cognitive functions, while mu waves are related to motor activity and are generally not predominant during sleep. Therefore, the presence of theta and delta waves is significant in characterizing the physiological and neurological features of NREM sleep, making this response the accurate choice.