What EEG finding is typically observed during REM sleep?

During REM sleep, the EEG is characterized by the presence of sawtooth waves. These waves are a distinct feature of REM sleep and are typically found in the central and occipital leads of the EEG. Sawtooth waves occur at a frequency of approximately 4 to 7 Hz and are named for their appearance, which resembles the teeth of a saw.

This finding is significant because it reflects the unique brain activity that occurs during REM sleep, a stage associated with dreaming and heightened brain activity. The presence of sawtooth waves signifies that the brain is in a state where it is more active, similar to wakefulness, contrasting with the more rhythmic patterns observed in non-REM sleep stages. In non-REM sleep, you would find spindles, delta waves, or posts, depending on the specific stage, but these are not representative of REM sleep.

Understanding these EEG characteristics is important for differentiating sleep stages and assessing sleep disorders, which can significantly impact clinical evaluations and treatments.