Psychophysiological Evaluation of a Chronobiologically Adapted Light Management System

Field Study With Elderly Dementia Patients

Project Justification

Previous research indicates that an increased proportion of blue light has a physiologically activating and emotionally stabilizing effect. Nonetheless, its impact on patients with neurodegenerative diseases as confounding factor remains unclear. Against this background, the use and effect of an intelligent chronobiologically adapted light management system in the context of neurodegenerative diseases are evaluated. The aim is to investigate the non-visual effects on the mental and physical health of people with dementia living in a care-therapeutic facility in comparison with an independent control facility.

Care-therapeutic facility

Our Approach

Within the study, general demographic and facility-related data was collected. Furthermore, the general and situational anxiety of the participants was examined and a cognitive screening was carried to check and classify the presence of cognitive impairments. Moreover, the participants’ perceived sleepiness as well as personal perception of lighting were collected. In addition to the psychological assessment procedures, the study also included an endocrinological analysis. Therefore, hormone levels of cortisol, progesterone and testosterone were measured via endocrinal hair analysis.

Procedure of the endocrinological hair sample analysis   

Insights and Outcomes

The results suggest that chronobiologically adapted lighting has a positive physiological impact on patients with dementia and can be interpreted as protective factor to prevent age-related decline in cortisol secretion. Subjects in the chronobiologically modified lighting condition reported less daytime sleepiness, higher levels of physiological activity and energy as well as an overall higher satisfaction with environmental lighting conditions than the control group. Results of the hair analysis showed higher levels of cortisol when exposed to chronobiologically modified lighting. Therefore, the implementation of chronobiologically adapted lighting systems in care facilities for patients with dementia promises to have a positive impact on the quality of the care.