Light as a modulator of emotion and cognition: Lessons learned from studying a diurnal rodent.

Light as a modulator of emotion and cognition: Lessons learned from studying a diurnal rodent. Horm Behav. 2018 Sep 19;: Authors: Yan L, Lonstein JS, Nunez AA Abstract Light profoundly affects the behavior and physiology of almost all animals, including humans. One such effect in humans is that the level of illumination during the day positively contributes to affective well-being and cognitive function. However, the neural mechanisms underlying the effects of daytime light intensity on affect and cognition are poorly understood. One barrier for progress in this area is that almost all laboratory animal models studied are nocturnal. There are substantial differences in how light affects nocturnal and diurnal species, e.g., light induces sleep in nocturnal mammals and wakefulness in diurnal ones, like humans. Therefore, the mechanisms through which light modulates affect and cognition must differ between the chronotypes. To further understand the neural pathways mediating how ambient light modulates affect and cognition, our recent work has developed a diurnal rodent model, the Nile grass rat (Arvicanthis niloticus), by chronically manipulating daytime light intensity in grass rats housed under the same 12:12 hour light/dark cycle. This simulates lighting conditions during summer-like bright sunny days vs. winter-like dim cloudy days. Our work has revealed that chronic dim daylight intensity results in higher depression- and anxiety...
Source: Hormones and Behavior - Category: Endocrinology Authors: Tags: Horm Behav Source Type: research