RESUMEN
This paper deals with the conception of a new system for sleep staging in ambulatory conditions. Sleep recording is performed by means of five electrodes: two temporal, two frontal and a reference. This configuration enables to avoid the chin area to enhance the quality of the muscular signal and the hair region for patient convenience. The electroencephalopgram (EEG), eletromyogram (EMG), and electrooculogram (EOG) signals are separated using the Independent Component Analysis approach. The system is compared to a standard sleep analysis system using polysomnographic recordings of 14 patients. The overall concordance of 67.2% is achieved between the two systems. Based on the validation results and the computational efficiency we recommend the clinical use of the proposed system in a commercial sleep analysis platform.
Asunto(s)
Algoritmos , Diagnóstico por Computador/métodos , Monitoreo Ambulatorio/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Polisomnografía/métodos , Síndromes de la Apnea del Sueño/diagnóstico , Fases del Sueño , Inteligencia Artificial , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The purpose of this study was to determine the effect of the level of physical activity in older women on heart rate (HR) response to its neural control at rest and during exercise by using heart rate variability (HRV) analysis. Electrocardiogram (ECG) was recorded in 3 (low, moderately, and highly) active groups of older women at rest and during submaximal exercise. Spectral HRV indexes were obtained from the ECG signal. At rest, highly active subjects have low HR without any alteration of HRV. During incremental submaximal exercise, parasympathetic modulations of HR decreased only in the highly active subjects (p <.01) without any alteration of HR, compared with the other groups. In older women, the effects of the level of physical activity on HR and HRV are dissociated. Quite a high level of physical training induces a higher sensitivity of sinus node response to the autonomic nervous system during exercise.