Psychophysiological Evaluation of a Chronobiologically Adapted Light Management System

Field Study With Elderly Dementia Patients

Project Justification

Previous research has shown that increased proportions of blue light can exert physiologically activating and emotionally stabilizing effects through non-visual pathways. However, the extent to which these effects apply to individuals with neurodegenerative conditions – such as dementia – remains insufficiently understood due to potential confounding factors related to disease pathology.

Against this background, the present study evaluates the implementation and impact of an intelligent, chronobiologically adapted light management system within a therapeutic care facility for individuals with dementia. The aim is to systematically investigate the non-visual effects of dynamic lighting on both mental and physical health outcomes.

This intervention group is compared to a control group housed in a similar facility without chronobiologically optimized lighting. By assessing parameters such as mood, cognitive function, behavioral symptoms, sleep–wake rhythms, and physiological markers, the study seeks to provide empirical evidence on the therapeutic potential of biologically informed lighting environments in neurogeriatric care settings.

Care-therapeutic facility

Our Approach

Within the scope of the study, general demographic information and facility-related parameters were documented to contextualize the sample characteristics. Psychological assessments included measures of both general and situational anxiety, alongside cognitive screening procedures to detect and classify the presence and severity of cognitive impairments.

In addition, participants reported their subjective sleepiness and provided individual evaluations of the perceived quality and characteristics of the lighting environment.

To complement these psychological and self-report measures, an endocrinological analysis was conducted. Hormonal concentrations of cortisol, progesterone, and testosterone were assessed through hair sample analysis, enabling the evaluation of long-term neuroendocrine activity. This multidimensional approach allowed for an integrated understanding of psychological, cognitive, and physiological responses to chronobiologically adapted lighting in individuals with neurodegenerative conditions.

Procedure of the endocrinological hair sample analysis   

Insights and Outcomes

The findings indicate that chronobiologically adapted lighting exerts a beneficial physiological effect on individuals with dementia and may serve as a protective factor against age-related declines in cortisol secretion. Participants exposed to the modified lighting conditions reported reduced daytime sleepiness, elevated levels of physiological activation and energy, and greater overall satisfaction with their lighting environment compared to the control group.

Endocrinological analysis via hair sampling further supported these results, revealing higher long-term cortisol concentrations in the intervention group – a marker associated with improved circadian regulation and stress adaptation.

These outcomes suggest that the implementation of chronobiologically optimized lighting systems in therapeutic and residential care settings holds considerable potential to enhance the quality of life and care for individuals with dementia by stabilizing circadian rhythms, supporting hormonal balance, and promoting overall well-being.