Aren’t eyes the most dominant of the five senses we human / animals possess?

• Most evolved? The optic nerve is a marvel of engineering.
• Most energy consuming? With almost half of primate brain involved in processing of visual information and stimuli, across 30 different areas in brain.

For all the wonders and indeed the privilege of eyesight, perversely enough, this week I started musing what might we be losing out in living a quotidian life filled with continuous visual stimulation except for 6-8 hours of sleep at night?

Not only dreams that come to us in moments of shut eye / sleep, but there are other moments recently when I felt numbed in sensation due to the overpowering stimulus of eyes. It is well known that the blind have heightened sense of space and sounds.

Couple of instances:

The first instance: Last week I attended the BBC proms – an exhibition of classical music in London (in Royal Albert Hall) that is a remarkable event in annual calendar spanning from July to September. And like most things English – there is much in form of tradition and loyalty around BBC proms. Spanning over 10 weeks or so, the proms are live performances by musicians and ensembles, broadcasted live on national television – the BBC. The live performances in Royal Albert Hall are packed with audience and last week, I attended with my 11 year old son the Proms 61. Sir Simon Rattle as the Chief Conductor of the Bavarian Radio Symphony Orchestra conducted Bruckner’s Fourth Symphony to a fully packed audience on that evening.

Now, more to the point – at various points during show, as I attempted to soak in the reverberating sounds of orchestra playing, I found my greatest immersion with my eyes closed. A remarkable and step jump in my sensory appreciation of the sounds of the symphony and as such a greater enjoyment of the musical spectacle. This was notwithstanding the visual spectacle of a full orchestra playing the Bruckner fourth with frenetic pace that my son remarked was superhuman in just physical exertion by string, vocal and drum artists over a period of 2 hours. And yet, for moment of pure blissful enjoyment – I had to close my eyes the orchestra in front of me so that I fully enjoy the music, elevated to another level.

The second instance is the rather common experience. Summer is over and oddly the temperatures fell in to single digits (⁰C) until today when the high pressure and warm temperatures returned. Yet sitting outside in garden under the winter (or autumn) sun – I had the urge to again shut eyes to fully experience the warm of sun.

Now it could be that my advancing middle age has dimmed my overall sensory faculties so I have to save one to fully experience another but I am assuming in good faith that this may be more fundamental, to the overpowering impact of visual stimulus and how much (perhaps evolutionarily) we consume of this form of sensory input, disproportionate to other 4 senses (of taste, smell, hearing, touch).

Taking to google research, there seems to some corroboration as suggested in the picture below which shows….

… brains acquire about 90% of information from two senses only: sight (about 80%) and hearing (about 10%). The remaining 10% of information is distributed between smell, touch, and taste senses Fig.1. The idea of reality built by brain is therefore mostly based on sight...

Now that provides closure 🙂 but still one sub-optimality remains. Unless one falls asleep, the act of shut eye is an active conscious endeavour and requires constant volition. Left to our human devices, the eyes will stay open until they can’t. This takes away from the aim of complete telesilence (can’t use radiosilence in this context!) or switching off of visual faculties at will. We may be moving in that direction though, with likes of Neuralink. Not a question of IF anymore, but WHEN? Who knows?