Genetic fuzzy classifier for sleep stage identification.

Soft-computing techniques are commonly used to detect medical phenomena and help with clinical diagnoses and treatment. In this work, we propose a design for a computerized sleep scoring method, which is based on a fuzzy classifier and a genetic algorithm (GA). We design the fuzzy classifier based on the GA using a single electroencephalogram (EEG) signal that detects differences in spectral features. Polysomnography was performed on four healthy young adults (males with a mean age of 27.5 years). The sleep classifier was designed using a sleep record and tested on the sleep records of the subjects. Our results show that the genetic fuzzy classifier (GFC) agreed with visual sleep staging approximately 84.6% of the time in detection of wakefulness (WA), shallow sleep (SS), deep sleep (DS), and rapid eye movement (REM) stages.

What factors are related to delayed treatment in individuals at high risk for psychosis?

BACKGROUND: Previous studies have shown that the individuals at high risk for psychosis suffer from depression, anxiety, and deficits in social functioning. The present report describes help-seeking behaviours, baseline psychopathology, and duration of attenuated psychotic symptoms (DUAPS) and their associations with other variables. METHODS: Using the Comprehensive Assessment of At-Risk Mental States (CAARMS), we conducted systematic evaluations of individuals at high risk for psychosis. Help-seeking behaviours, current Axis I diagnoses, DUAPS, and baseline psychopathology were investigated. Demographic and clinical characteristics of short and long DUAPS groups were compared. RESULTS: Thirty-eight subjects were recruited from nine centres. Participants seldom sought psychiatric services at their first help-seeking contact, and the mean DUAPS was 22.00 +/- 28.59 months. Most participants had current Axis I diagnoses, and depressive disorder NOS was the most common of these. Higher levels of depression, anxiety, obsessive-compulsive symptoms, and functional impairment were also identified. We found no significant differences between short and long DUAPS groups in baseline psychopathology. However, we observed significantly lesser distressing intensity of thought contents and significantly greater social impairment in the long-DUAPS group. CONCLUSION: These findings suggest that high-risk subjects frequently received delayed treatment despite symptomatic distress and functional impairment. No direct evidence supporting the delayed effect of the DUAPS on baseline psychopathology was found.