Fig. 8
From: Detection of cortical arousals in sleep using multimodal wearable sensors and machine learning
Accelerometer and gyroscope feature trends across sleep. The top panel (a) shows the standard deviation of the X-axis accelerometer signal, reflecting variability in leg movement amplitude. The bottom panel (b) displays the spectral entropy of the Z-axis gyroscope signal, which quantifies the irregularity or complexity of rotational motion. Red markers indicate windows labeled as arousals, while blue markers denote non-arousal periods.
