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Yes, that is absolutely pseodoscience. Your optic nerve actually is not passive at all.

(remember, I work in the Neural Engineering Center, and I did my Master's research in a part of the lab that worked on the eye -- my thesis was 'Development of the Full Model of the Rod Photoreceptor Cell', so this might be horribly boring.)


Here is a schematic picture of vision:



The eye kind of acts as a camera -- the pupil acts as the variable aperature, deciding how much light to let in to the eye, and it travels through the eye to the retina at the back of the eye where the information is processed and relayed to higher centers of the brain. It is almost like the retina acts as the film in a camera. (this is way oversimplified).

The retina is composed of 5 layers of cells. The photoreceptors (rods and cones) absorb the light and undergo a process called phototransduction. Simply, light is absorbed by a special memebrane spanning molecule, rhodopsin in rods, opsin in cones, and it undergoes a conformational change to opsin and retinol. This causes a cascade in events (which are described in my MS thesis ), eventually causing cGMP-gated cation channels to close, causing the cells to hyperpolarize (this is a passive decrease in membrane voltage). This hyperpolarization causes the rods or cones to release a neurotransmitter (glutamate) and activate the bipolar cells (a type of interneuron), and these cells in turn have a passive change in membrane potential, causing the release of glutamate at their synapses with ganglion cells. The axons of these ganglion cells form the optic nerve. (the other two cell layers are amacrine cells and horizontal cells which further modify the signal at each of the synapses above). The ganglion cells depolarize passively until the depolarization gets high enough so that at the trigger zone (axon hillock) of the ganglion cell axon the passive depolarizations' sum is greater than the axon's firing threshold, and the ganglion cell axon (optic nerve) fires an action potential (which is an active neural signal).

Thus, your optic nerve is not passive. It is an active signalling element.

To understand how neurons work, I referred my students in EBME 201 to this elementary neuroscience page . It's presented in a very well explained manner.

One way I can see that theory working is if instead of active/passive, he sort of meant that his visual system worked in reverse. If the higher centers of his brain gave some sort of signal that caused some light that he recieves in to be converted to a different type of light, producing heat / the ability to see through things. However, I can't think of how that works, because neurons are generally unidirectional (i.e. an action potential can only propogate one way). However, passive membrane changes are bidirectional.

Speaking of membrante potential changes, I wonder if somehow produces some kind of extra electricity -- like if he is somehow able to harvest the electric potentials created through his neuronal signalling, and convert this electric energy into heat energy.

I also wonder if his retina has some kind of special cell that is able to reflect the heat of the sun's rays off his retina and through his eye, allowing heat to emerge from his eye. That doesn't seem likely, though.

- Laura


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