On the Role of Cholesterol in the Vision Process

I have written elsewhere in this work about the role of the cholesterol molecule in the vision process. In summary, light interacts in the spaces between, and not within, retinal receptors. Energy from the interaction is transmitted orthogonal to the direction of incidence, i.e., in the plane of the pigment-containing thylakoid disks that are “coin stacked” within each receptor. The rhodopsin pigment molecules are contained within the bilipid membrane that forms the disks and are properly dichroically oriented to absorb energy from this direction.

Thus, light energy must be transmitted along (“in the plane of” or “through”) this membrane from the point of interaction on the receptor surface to the rhodopsin pigment molecules contained within the disks.

It is my contention that nature would have evolved a lossless mechanism for this energy transport. I believe that this has been accomplished in the form of the solitonic vibration. Solitons are a type of phononic (i.e., mechanical or “sound-like”) vibration that have the unique ability to transmit energy losslessly. An operative term here is coherent. A colleague of mine once used the analogy of wind blowing across a cornfield. Each cornstalk sways in the wind independently of the others with some “getting out of phase” the result being dissipation of the energy of the wind. This is somewhat the “general condition of things” and is the cause of red-shifting (i.e., energy loss) in biological light interaction. But, supposing that some sort of incompressible medium was placed between the individual stalks. The entire field would be constrained to move coherently and the energy loss from the random (some “out of phase”) swaying of individual stalks would be negated. This is the function of the cholesterol molecule contained within the bilipid membrane forming the thylakoid disk. The technical term is “intercalation”, i.e., each cholesterol molecule is of exactly the proper physical size to fit into the space between adjacent lipid molecules. Cholesterol-intercalated membrane allows lossless solitonic energy transport. This is the role of cholesterol.

I am always surprised with all of the attention given to the cholesterol molecule that this physics-based role seems never to be mentioned.

I have discussed elsewhere on this page the meaning of Hans Kuhn’s “photon funnel” experiment that supports the above assertion. Kuhn substituted the size-optimized octadecane molecule for cholesterol in artificial light absorbing (Langmuir Blodgett) layers and achieved what can only be explained by a lossless solitonic energy transport mechanism.

GCH