What is the minimum peak-to-peak voltage needed to identify a K complex?

In polysomnography, a K complex is defined as a specific waveform that occurs during sleep, often associated with the onset of sleep or the presence of arousals. One important aspect of identifying K complexes is that they are not strictly defined by a specific minimum peak-to-peak voltage. Instead, criteria for identifying K complexes focus more on their morphology, timing, and relationship to other sleep stages rather than a standardized voltage threshold.

Unlike some other EEG phenomena, K complexes can be present with varying amplitudes and still be considered valid. Thus, rather than looking for a specific voltage measurement, clinicians rely on the morphology and contextual presence of K complexes during the sleep cycle. This variability allows for more flexibility in interpretation, which is essential for accurately scoring sleep stages and diagnosing sleep disorders.

Therefore, the option indicating that there is no stipulated minimum peak-to-peak voltage reflects the understanding that identifying a K complex is based primarily on its shape and timing rather than a numeric voltage threshold.