# Mathematical model of light and circadian data improves sleep timing in people with schizophrenia
Disturbed sleep timing in people living with schizophrenia is more likely to be related to light exposure than to intrinsic biological factors.
Application of a physiologically-based mathematical model to light exposure, sleep timing data and biological markers of the circadian clock, has revealed that disturbed sleep timing in people living with schizophrenia is more likely to be related to light exposure than to intrinsic biological factors. Surprisingly, the combination of the mathematical model and digital health data suggested that normalization of disturbed sleep timing can be achieved by improving light availability and does not require the imposition of altered sleep timing or sitting in front of light boxes as recommended in current bright light intervention therapies.