Which activity is not included in the EEG signs of normal drowsiness during stage one sleep?

In the context of stage one sleep, normal drowsiness is characterized by specific EEG patterns that signify the transition from wakefulness to sleep. Among these patterns, midline theta activity is commonly observed, reflecting a state of relaxed wakefulness or drowsiness. Additionally, alpha attenuation is a well-documented phenomenon during this transition, where the typical alpha waves diminish as a person begins to fall asleep.

Slow-wave activity, while more prominent in deeper stages of sleep, can also appear during stage one but is not considered a hallmark pattern of normal drowsiness.

On the other hand, left anterior temporal delta activity is not a typical sign of normal drowsiness. Delta waves are associated with deeper stages of sleep, particularly stage three or four, and a significant presence of delta activity in the anterior temporal region during stage one would be atypical. Therefore, identifying left anterior temporal delta activity as not being part of the EEG signs of normal drowsiness aligns with the recognized patterns that characterize this early sleep stage.