Lightcap 1: Fundamentals of light’s impact

Light is one of our most valuable resources on this earth. It makes the world visible to us, is the major driver of the 24-hr sleep-wake cycle to which not only humans, but virtually all life on earth (fauna and flora) submits.

In fact, there would be no life on earth without light. It is therefore hard to overestimate the impact light has on humans, biologically, psychologically, socially.

And yet, we hardly ever think or speak about light. LIGHTCAP’s 1 ‘Behind the scenes’ will provide fundamental knowledge about visual and non-visual systems in the brain and about the way in which light interacts with relevant brain systems and regions. It closes with a brief perspective on the ways that we can benefit from light. The course is one in a series of four, each with a different disciplinary basis and with complementary perspectives to the domain of light for humans. The basis of this course is mostly neuroscience.

In this course you will: (1) learn how photoreceptors detect light, what cell types exist in the retina, how they are arranged, and how this allows the retina to detect light and extract visual information (2) learn about a novel photoreceptor — melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs) — and understand how melanopsin acts to sense light and how it contributes to non-image forming vision (3) learn basic knowledge about brain pathways from ipRGCs to relevant brain regions and how we came to know about them (4) be introduced to the body clock, circadian rhythmicity, how light acts on the body clock, and how, in turn, the clock influences numerous functions in our body (5) dive deeper into a specific neural substrate: the locus coeruleus (also termed blue spot) – its anatomy, firing patterns and projections, and the functions of the LC and its relationship with light (6) get a basic introduction of brain imaging techniques that are being used to study the pathways and effects of light in humans and explains the working of, rationale for, MRI, fMRI and EEG in somewhat more detail (7) be introduced to the basic concepts of metamerism and its potential usage in neuroscience and research on light in particular (8) be introduced to the many relationships between light and health