Anesthesia EEG Simulator - Dra. Carolina Frederico.

Simulation

Preset Coupling strength 0.75 Preferred phase 90 deg Delta frequency 0.50 Hz Alpha frequency 10.0 Hz Alpha amplitude 0.45 Noise level 0.12

Readout

Modulation Index 0.0000

Phase label Peak-oriented

Window 8 s

Slow delta rhythm

Standard phase convention: 90 deg = delta peak

Alpha rhythm modulated by delta phase

Black: delta + alpha, red: alpha rhythm, green: amplitude envelope

Phase reference

Current delta phase

Phase-amplitude histogram

Mean alpha amplitude by delta phase

Clinical idea: PAC is not simply more alpha or more delta. It describes whether alpha amplitude is organized by the phase of a slower rhythm. The number is useful only together with the spectrogram, signal quality, drug state, and brain vulnerability.