Cortical activation in REM behavior disorder mimics voluntary movement. An electroencephalography study

Area of Science:

• Neuroscience
• Sleep Medicine
• Movement Disorders

Background:

• Parkinson's disease (PD) is a neurodegenerative disorder affecting motor control.
• REM sleep behavior disorder (RBD) involves acting out dreams, often preceding PD diagnosis.
• Motor symptom fluctuations in PD, including improvement during RBD movement episodes, suggest a link between sleep and motor control.

Purpose of the Study:

• To investigate cortical activity during movement episodes in REM sleep behavior disorder (RBD).
• To compare cortical involvement in RBD patients with and without Parkinson's disease (PD).
• To explore the relationship between cortical activity and the generation of electromyographic activity during RBD movements.

Main Methods:

• Retrospective analysis of polysomnography data from 15 patients with RBD (7 idiopathic, 8 with PD).
• Selection of REM sleep segments with electromyographic (EMG) activity indicating movement.
• Analysis of electroencephalographic (EEG) signals, including premotor potential and time/frequency transforms, to assess movement-related cortical changes.

Main Results:

• A premotor potential was identified preceding EMG activity during RBD movements.
• A decrease in alpha-beta oscillatory activity and an increase in gamma activity were observed during movements.
• These EEG changes were consistent in both idiopathic RBD and RBD associated with Parkinson's disease.

Conclusions:

• Movement-related cortical activity in RBD is characterized by specific EEG patterns, including premotor potentials and altered oscillatory activity.
• These findings are similar in patients with and without Parkinson's disease, indicating a common cortical mechanism.
• The results suggest significant cortical involvement in the generation of movements during REM sleep in RBD.