Ambulatory Artifact 3 ECG 3 Ear ear electroencephalogram 3 Electrocardiography 3 Electroencephalogram signals 3 Electroencephalography 3 HRV 3 Heart rate variability 3 Monitoring 3 Monitoring system 3 Neurology 3 PPG 3 PTT 3 Photoplethysmogram 3 Pulse travel 3 Pulse travel time 3 Travel time 3 Travel-time 3 Wearable technology 3 ambulatory 3 artifacts 3 ear EEG 3 epilepsy 3 monitoring system 3 wearable 3 Anesthesia 1 Anesthesia, Conduction 1 Humans 1 Laparoscopic surgery 1