Successful candidacy exam at LIPID

Catherine's thesis will focus on the magic of daylight in driving physiological responses to light.

Light exposure holds a powerful influence on our brain and biology. Through melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), it drives a wide range of non-image-forming responses (also known as non-visual effects) determinants of human health, cognition and behavior. This biological response to light was shaped over millennia as an evolutionary consequence to daylight’s dynamically changing cycle and characteristics. Over the last centuries, modern society outgrew the outdoors and began to rely increasingly more on electric sources of light interfering with the natural dark-light cycle. Although numerous studies have assessed daylight’s upper hand over electrical light regarding its beneficial effects to maintain a healthy living, research has yet to establish a factual basis on the driving causes of this variation. In the present project, the aim is to provide empirical evidence on whether specific characteristics distinguishing daylight from electrical light lead to significant variations in physiological effects and in cognition. Through a series of experimental conditions, the idea is to isolate and compare the influence of selected properties of daylight and electric light exposure on several non-visual effects related to physiology and cognition. To broaden the scope, it will be further investogated whether these variations correlate with differences in perceptual experience of daylight and electrical light. Lastly, variations in neural activity wil be explored between daylight and electric light exposures to identify key predictors of their influence on non-visual effects.