ipRGC

Our eyes are amazing and we now realize that they are for so much more than just vision.  In 2001 Intrinsic Photo Receptive Ganglion Cells were discovered.  In addition to the rods and cones which enable us to see colors and focus, as well as to make out shapes and contrast in dim lighting, these ipRGC’s have nothing to do with our vision. 

87% of our sensory information received is by sight, 50% of our brain is used for vision and yet within our eyes are also these ganglion cells, many of which we still don’t know what functions they perform.  We now do know that the ipRGC’s send information to the part of our brain associated with short term memory as well as our circadian rhythm.  These ganglion cells absorb light, especially blue light which is essential for the entrainment of our circadian rhythm (see blog on Circadian Rhythm). 

There is so much more to learn about our eyes and how they influence our health, with the discovery of these ipRGC’s we have gained the understanding that our eyes are essential for many of our biological functions. 

Circadian Rhythm

Diagram By NoNameGYassineMrabetTalk  ✉   fixed by Addicted04 - Wikipedia

Diagram By NoNameGYassineMrabetTalk fixed by Addicted04 - Wikipedia

Circa-about   dia- day

These are our natural rhythms that repeat in about a 24 hour day.  These are vital for our health and are able to get out of sync – just think of jet lag.  Our circadian rhythm is reset every day – this is called entrainment.  To reset we need bright light in the morning to signal the production of serotonin, and we need dimming light and darkness at night for the production of melatonin.  Both light and darkness are essential for a healthy circadian rhythm.

So many aspect of our lives are regulated by our circadian rhythm, our sleep, mental functioning, emotions, state of mind and many aspects of our immune system and health. 

How can we adjust and improve this essential part of our biology?  Bright light in the morning upon waking, being outside in daylight for at least 20 minutes a day preferably around noon time when the sun is the brightest, exercise, a shift in indoor lighting in the evening to a softer yellower light and avoiding the blue light from electronics for at least 1 hour before bedtime.  Sleeping in total darkness is also important and getting 8 hours of sleep a night, our ancestors before electricity got 10 hours. 

Some current research is suggesting that healthy sleep and a healthy circadian rhythm is an important factor in preventing many of the disease that plague us, heart disease, cancer, obesity, diabetes and Alzheimer’s disease.