You’ve All Seen Them: Phosphenes

What are phosphenes?

The other day, a former student of mine contacted me and wanted to know if I could explain to him what phosphenes were. He had recently come across that term, when he had tried to find an explanation for the coloured patterns that had appeared “in his head”, even though his eyes had been closed. The term ‘phosphene’ combines the Greek words ‘phos’ (= light) and ‘phainein’ (= to show) or ‘phenomenon’ and refers to images that are generated in the brain and that people “see” with closed eyes. The images are not stationary and usually consist of wavy, circular, striped or rapidly changing and usually multi-coloured cloud-like patters that can be frighteningly intense and may, in the past, have been the explanations for the visions that religious mystics have reported.

Visual patterns of these kinds are apparently more frequently experienced by children than adults, but they can and do occur in anyone’s brain and are likely to be present also in animals. But what are they, what causes them and how can their “existence” be proven, let alone be explained? They cannot, after all, be photographed, measured or counted.   – and yet, we do know they exist and manifest themselves in the sensations we describe as phosphenes. Following the publication of my 2009 book “Bioluminescence in Focus  – a collection of illuminating essays”, which contained one chapter on ultraweak photo emissions by Dr Bajpai, the Hungarian phosphene researcher Dr. István Bókkon approached me and we exchanged some ideas.

According to Bókkon the visual sensation of phosphenes is due to the intrinsic perception of ultraweak bioluminescent photon emissions. That biophotons are ‘real’ and do exist in all living organisms is an undisputed fact (and one of my blogs was devoted to them: “Biophotons do exist, but then so what?“), but questions as to their generation, role and indeed perception are still largely unanswered. Phosphenes can occur randomly, but are readily inducible by pressure (for example a blow on the head or a punch in the eye, causing the injured “to see stars”), by electrical and transcranial magnetic field stimulation, by psychotic conditions, and certain diseases (migraine for instance) and, of course, by innumerable drugs (such as nicotine, cocaine, amphetamine, morphine, etc.) as well as alcohol. All these different forms of stimulation, according to Bókkon, lead to oxidative damage and the production of free radicals and their cellular effects on lipid peroxidation, mitochondrial respiration, oxidation of the amino acids tyrosine and tryptophane residues in proteins. 

Electrical brain stimulation of the visual cortex with a few micro- to milli-amperes with electrodes were able to elicit phosphenes in sighted as well as blind people and since the brain does indeed generate ultraweak biophotons, the question is whether the amount and production of such biophotons are affected by the stimulation and whether the biophotons can be perceived. Bókkon suggests that the biochemical reactions elicited by the various forms of stimulation lead to an uncontrolled overproduction of free radicals, which are the main source of the ultraweak photon emissions, but depend on the neural activity and oxygen concentration in the brain. In several regions of the brain, the cerebral cortex, the pineal, the cerebellum, etc, molecules are present that can interact with the biophotons, thereby causing the sensation of phosphenes. He points out that opsins are not just the rhodopsin (i.e., the visual pigment in photoreceprive cells of our eye’s retina, giving us “vision”), but that multiple kinds of opsins, for example encephalopsin, neuropsins, etc. (all capable of interacting with photons), have been detected in multiple regions of the brain. 

Although undoubtedly a part of a human brain’s activity and function, phosphenes are difficult to investigate. We know they are there and can be generated, but to experimentally manipulate them, to quantitatively record and analyse them, still poses challenges that need to be mastered before one can assign a functional role to them, which according to some could eventually lead to “mind-to-mind communication technology” and help the blind to “see”. Wishful thinking? Who knows.  

© Dr V.B. Meyer-Rochow and, 2022. Unauthorized use and/or duplication of this material without express and written permission from this site’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to V.B Meyer-Rochow and with appropriate and specific direction to the original content.

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Head- and Brainless

Is learning something then still possible?

I love the questions that children have. Why isn’t the sun alive? What would happen if we had eyes also on the back of our head, like spiders? And, can we live without a brain?

Well, occasionally anencephalic children are born and they lack almost the entire brain. Few live longer than a few days after birth, but there is a case of an anencephalic infant having been kept alive for almost 3 years. And there is the famous legend of the 15th-century pirate Klaus Störtebeker, who was captured to be beheaded along with his crew. According to the legend, he struck a deal with the executioner that those men of his crew that he’d run past, after being decapitated, should get their freedom. And how many men did the headless Störtebeker then pass in order to save them: 11 according to the legend. —>—>

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Give a Little – and Take a Little

Increases of some structures appear to parallel decreases in others

It seems odd, but no animal with horns or antlers, whether fossil or recent, has all the teeth required to give it the complete and full dentition characteristics of mammals. No species of spider is known to possess the ability to sting, but all have a poisonous bite (although, luckily only a few possess poisons potent enough to harm humans). The most colourful birds like tropical parrots and Papua New Guinea birds-of-paradise leave a lot to be desired when it comes to their ability to sing and the increase in swim speeds of fish like the tuna apparently went hand in hand with the loss of the buoyancy organ, the swim bladder. There are lots more of such examples, but what am I trying to demonstrate with these examples? I’m trying to show that the development in one area frequently has consequences in another and that a “push” in one evolutionary direction can see a reversal in another. —>—>