Light for health   Eye health

Health Implications of Ocular Light

Health Implications of Ocular Light

- Why the best way to shift your Autonomic Nervous System from Sympathetic to Parasympathetic dominance is by means of the Eyes.

- Why the proportion of Central/Focused Vision to Peripheral/Diffused Vision is important

- Why Glasses, Contact Lenses, and Refractive Surgery can cause systemic illness

- Why Heavy Metal Poisoning and Light Hyper Sensitivity can be connected


- Why the Hypothalamus is central to the understanding of our present civilization and the current Health Plagues (lack of Synchronization with Nature)

by Nikolaj Holtermann, MSc

I am inspired a.o. by the work of eye surgeons Dr. Prentice (USA) and Dr. Hollwich (Germany), who documented the profound influence of ocular light on the human organism.

The work of Dr. Prentice
Dr. Prentice was looking for eye strain in all the eyes muscles using plus lenses (reading glasses for fogging the eye sight) and prisms, and using physical health changes as indicators of how to proceed. The ciliary muscle is one of seven eye muscles involved, but an important one, as it controls the degree of refraction of the crystalline eye lens, and is involved in the high prevalence of myopia (nearsightedness) nowadays.

According to Dr. Prentice in his book, The Eye in its Relation to Health (and here), myopia is caused by abnormal nerve innervations and imbalances in the ocular muscles due to excessive nearwork. As soon as these muscles are balanced/relaxed by avoiding minus-lenses, and instead use "fogging" by plus-lenses (reading glasses), the abnormal nerve innervation would cease, and often impressive improvements in general/systemic health conditions occur. Dr. Prentice has seen improvement and cure in a.o. diabetes, nervous system disorders, and wasting conditions.

The mechanism involved, is a relaxation of the ciliary muscle, since it will not have to stress anymore to perform accommodation for near focus work, as it did, when the patient was wearing minus lenses (allowing for far vision).

This article is especially focusing on the ciliary muscle, and how to avoid strain and stress on this muscle to avoid spasms and nervous and muscular system stress because of abnormal nerve innervations related to this parasympathetically connected muscle (through Cranial Nerve III, CN III, or here). Dr. Prentice showed, the validity of his theories in many cases like mine with neuroendocrine involvement.

Judging from the work and many cases of Dr. Prentice, it seems there exist a certain, abrupt value/threshold/limit (in millivolt), where the chronic, abnormal nerve innervation to the eye accommodative processes will stop, and tension in the nervous and muscular system will be released. It seems, this amount (potential in mv), in practice, can be translated to a specific value/figure of dioptres for a given individual. Like this, many of his patients experience a sudden, abrupt relieve from symptoms, when reaching their individual level, it seems, from reading the many case stories in the book of Dr. Prentice.

Another interesting work was done by R.F. Fisher, who calculated The force of contraction of the human ciliary muscle during accommodation (in newton, N) for a given amount of dioptres.

Using plus lenses instead of minus lenses for the myopic person, of course also causes a shift from focused (central, foveal) vision through the central ocular light pathways towards peripheral vision characterized by spread and diffused light on the peripheral retina.

Focused vision versus peripheral vision
All the Eye media involved in the central ocular light pathways (focused, foveal vision) are connected to the sympathetic division of the Autonomic Nervous System (ANS) and accompanies accommodation for far vision.
This applies to the pupillodilatormuscles, cones (and here) (cones are dominating in the central macula/fovea region), the Retino-Hypothalamic Tract (RHT, and here, here (rats), here (horses), here (related to animals, link in german)) conducting light (or more precisely photo current) to the three light sensitive brain glands (Hypothalamus (same german link), pituitary and pineal (and here, here) glands) through the Suprachiasmatic nucleus (SCN);

as opposed to

peripheral ocular light pathways (peripheral vision)
(iris, pupillary constrictor (iris sphincter muscle), ciliary muscle (contraction), rods (rods are dominating in the peripheral retinal region), that are parasympathetically related and accompanies accommodation for near vision.

Therefore, myopia (because of the spread, diffused light on the retina) will cause an ANS shift to the parasympathetic side, while emmetropia (0, plano) for many people, especially those with nervous system disorders will shift the ANS to sympathetic dominance and sometimes chronic stress.

This shows to me, that 0D (zero, plano in vision terms) is not always zero (or the point of balance) in health terms. To some people, -2D, -4D or even -6D in cases of neuroendocrine disorders, might be the point of health balance, and could be the considered target in refraction. In cases of lost accommodation (and maybe myopia and ciliary muscle strain) as well as neurological problems, these patients might benefit from keeping their near vision (demanding glasses for far vision activities such as driving a car) instead of keeping their far vision (demanding glasses for near vision activities such as reading and computer work) after e.g. refractive surgery, not only because of issues related to vision, but also to health and well being of the patient.

The work of Dr. Hollwich on especially the chemical (endocrine, hormonal, metabolic) effects of ocular light
Dr. Hollwich throughout his life investigated the sympathetic stimulating effects on the brain glands and the biological organism of light through the central ocular pathways and the RHT. To normal, healthy individuals, there are obvious beneficial effects from ocular light stimulation through the RHT, as shown by Dr. Hollwich. He showed, that ocular light to a high degree controls hormonal production in the brain glands via the RHT. The following abstract is a good example of his work:

"Klin Monbl Augenheilkd. 1989 Nov;195(5):284-90.

[Effect of light on the eye on metabolism and hormones].

[Article in German]


Numerous metabolic parameters in serum and urine were examined in 110 cataract patients before and after cataract surgery. The marked reduction in light passing through the eye due to opacities (vision less than 1/10) leads to characteristic metabolic and hormonal disturbances. ACTH and cortisol production decreases, metabolism slows down and due to an adrenal insufficiency for which the pituitary is responsible there are characteristic changes in the cortisol-dependent metabolic processes. In addition, an "energetic action" of the light affecting the hypothalamus via the retino-hypothalamic pathways (the "energetic portion" of the visual pathway) was proved in patients who were blinded by cataract and had metabolic disturbances as a result. Postoperatively, after elimination of the lens opacities, the metabolism and hormones of the same patients returned to normal. As a result of restoration of exogenous light stimulation to the diencephalon-hypophysis system via the retinohypothalamic pathway ("energetic pathway" of the optic system) the metabolism and hormones returned to normal during the patients' stay in the hospital. These comparative investigations in the same patients before and after cataract extraction provide for the first time irrefutable scientific evidence of the influence of light via the eye on the human organism.

PMID: 2557485 [PubMed - indexed for MEDLINE]"
Other examples are to be found here, here, here, and here. As shown in the references, restoration of central ocular light pathways to the brain glands through the RHT by removing cataracts installs normalization of metabolism, hormonal and blood levels.

Many other researchers have confirmed his pioneering work, one example is Joseph N Trachtman: Optometry (St. Louis, Mo.). 02/2010; 81(2):100-115. DOI: 10.1016/j.optm.2009.07.016: Vision and the hypothalamus, in which he states in the Abstract:

"For nearly 2 millennia, signs of hypothalamic-related vision disorders have been noticed as illustrated by paintings and drawings of that time of undiagnosed Horner's syndrome. It was not until the 1800s, however, that specific connections between the hypothalamus and the vision system were discovered. With a fuller elaboration of the autonomic nervous system in the early to mid 1900s, many more pathways were discovered. The more recently discovered retinohypothalamic tracts show the extent and influence of light stimulation on hypothalamic function and bodily processes. The hypothalamus maintains its myriad connections via neural pathways, such as with the pituitary and pineal glands; the chemical messengers of the peptides, cytokines, and neurotransmitters; and the nitric oxide mechanism. As a result of these connections, the hypothalamus has involvement in many degenerative diseases. A complete feedback mechanism between the eye and hypothalamus is established by the retinohypothalamic tracts and the ciliary nerves innervating the anterior pole of the eye and the retina. A discussion of hypothalamic-related vision disorders includes neurologic syndromes, the lacrimal system, the retina, and ocular inflammation. Tables and figures have been used to aid in the explanation of the many connections and chemicals controlled by the hypothalamus. The understanding of the functions of the hypothalamus will allow the clinician to gain better insight into the many pathologies associated between the vision system and the hypothalamus. In the future, it may be possible that some ocular disease treatments will be via direct action on hypothalamic function."

Therefore, by controlling ocular light, it is possible to control hormonal production in the biological organism (here).

Japanese researchers a.o. has also recently confirmed the previous research by Dr. Hollwich on the profound, sympathetically stimulating effects on the biological organism by ocular light through the RHT. Hachiro NAKAGAWA and Nobuaki OKUMURA: Proc. Jpn. Acad., Ser. B, Vol. 86, 391-409 (2010): Coordinated regulation of circadian rhythms and homeostasis by the suprachiasmatic nucleus:
"It has been also shown by electrophysiological means that light exposure to rat eye enhances sympathetic nerve activity, whereas it depresses parasympathetic nerve activity. Thus, environmental light is implicated not only in the phase-shift through the retinohypthalamic tract (RHT), but also control of autonomic nerve activities through the RHT, It is also discussed in this review how the two divisions are interconnected and how environmental light is involved in this interconnection."

Another interesting study is by Ruiter M, Buijs RM, Kalsbeek A. titled "Hormones and the autonomic nervous system are involved in suprachiasmatic nucleus modulation of glucose homeostasis".

So, ocular light and focused vision, through the RHT under normal circumstances causes an upregulation of the Pituitary axes (P-Adrenal, P-Thyroid, P-Gonadal) and a downregulation of the "night gland", the pineal (which through inhibitory light stimuli functions antagonistically to the Pituitary, that masters the day functions) as well as vagal pancreatic and hepatic nerves.

Light stress
Besides the beneficial, stimulating effect of central, ocular light, there is also the possibility of hyperactivity and stress from the sympathetically stimulated central, ocular light (foveal, focused vision), light stress or light pollution, as also shown by Dr. Hollwich. In his book, The influence of ocular light perception on metabolism in man and in animal, he writes the following about light pollution at page 90:

"It must be emphasized here that the numerous effects of light on the human and animal organism... do not only produce a "natural beneficial stimulation" of the Pituitary gland and the Adrenal Cortex; if the stimulus becomes too strong, they bring about an unspecific stress reaction."

Later on at page 93, he continues about the same subject:

"Intense Photostimulus causes increased secretion of ACTH and cortisol... and as a result, work performance increases during the first hours of exposure, only to decline sharply thereafter".

To the individual with a stressed brain and nervous system, this may cause the following reaction. When normal amounts of nerve impulses (or photo current) (as in 0D, plano) reaches the visual cortex for vision, then normal amounts of nerve impulses also reaches the three (light sensitive) brain glands (Hypothalamus, Pituitary, Pineal) through the RHT. In these glands, however, normal amounts of nerve impulses can cause a hyper-reaction due to conditions such as infection, structural damage or excessive accumulation of (heavy-) metals, such as mercury and copper. Heavy metals have a high affinity for fatty tissues such as found in the brain (glands), nerves, and cell membranes. Especially copper with its high electrical conductivity (the reason for using copper in electrical wires) will increase the activity of these regions by working as an antenna and transmitter of nerve currents. This can be the reason why heavy metal poisoned individuals often exhibit light hyper sensitivity.

Being the first of these glands to receive retinal nerve impulses through the RHT, the Hypothalamus is a very important controlling gland in the human body. One could say, it is mastering the physical (electrical, energetical) as well as the chemical (hormonal, endocrine) world in the human organism.

The physical part is through the neurological part and the nervous systems. The Autonomic Nervous System (ANS), with its subdivision into the sympathetic and the parasympathetic compartment are thus highly controlled by ocular light.

The chemical part, through the endocrine system, is also highly controlled by ocular light, e.g. through hypothalamic control of the Pituitary and related glands and endocrine bodies in the organism (e.g. the HPA axis). Basically, endocrine secretion of all chemicals in the body is governed by these three controlling glands, so even the blood chemistry and cell chemistry is affected.

As the Hypothalamus communicates with the autonomous nervous system via neural signals and the endocrine system via endocrine signals (chemical signals which travel through the bloodstream), the hypothalamus is a very important organ in the human body.

One of the chief functions of the hypothalamus is control and integration of activities of the autonomic nervous system (ANS). The ANS regulates contraction of smooth muscle and cardiac muscle, along with secretions of many endocrine organs such as the thyroid gland (associated with many metabolic disorders). Through the ANS, the hypothalamus is the main regulator of visceral activities, such as heart rate, movement of food through the gastrointestinal tract, and contraction of the urinary bladder.

The physical (electrical) effects of ocular light
It is mentioned earlier in this article, how ocular light shifts the ANS between sympathetic and parasympathetic dominance. These compartments also relate to changes from a contracted state (sympathetic related) to an expanded state (parasympathetic related).

Contraction of the eye lens by the parasympathetically innervated ciliary muscle causes expansion of the light on the retina, which is in accordance with parasympathetic activity. So, it seems, the eye sight - again - is upside down. It is a mirror of the outside world. What seems to be a contraction of a muscle leads in practice to the opposite for the rest of the body - expansion - and then to relaxation, regeneration, healing, and an anabolic condition.

Here is a more thorough explanation of the relationship between the sympathetic-parasympathetic divisions and the contraction and expansion activities going on in the human organism:
"Orgone energy was originally observed by Wilhelm Reich, MD, a psychoanalyst in the late 1920s, as a bio-electrical charge whose flow within the body could be visibly seen as waves passing through his clinical patients as they were experiencing intense emotional breakthroughs. (1) Later, in the 1930s, to confirm his visual observations, Reich was able to objectively measure the movements of this energy by using a very sensitive millivolt meter with sensors attached to the body to record subtle bio-electric charge. He found the energy flowed from the inside body core to the outside surface (towards the world) when a person felt pleasure or expansion; and conversely, it flowed from the surface to the interior (away from the world) during states of anxiety, fear, and contraction. (2)

Reich also noted that the conditions of expansion and contraction affected a person, not only emotionally, but down to the autonomic nervous system, to the cellular, and even chemical levels. (3) States of expansion produce parasympathetic conditions associated with dilation of the blood vessels and increased circulation, pain relief, better digestion and peristalsis, lower blood pressure; and the stimulation of potassium and lecithin production; along with creating a sense of well-being, and sexual excitement. States of contraction, however, produce sympathetic effects: constricted blood vessels, less blood flow, and often pain. In addition, the contracted condition increases blood pressure and heart beat rate, adrenaline flow and cholesterol; it inhibits digestion and blood supply to the genitals and is associated with the emotions of anxiety and "stress".

The ability of the body to expand and contract and not become "stuck" in one mode, created what Reich called the pulsation of life which distinguished the living from the non-living. This pulsation of expansion and contraction also followed a specific four-beat rhythm:

Tension - Charge - Discharge - Relaxation

Reich observed this energy pattern within the organs of the body: from the beat of the heart, to peristaltic movements of the intestine, the bladder, and especially obvious in the sexual function of orgastic discharge. He called this pulsating pattern the function of the orgasm or the Life Formula."

Conditions with sympathetic ANS involvement
.....coming soon....

This leads to my conclusion regarding the influence of the eyes on the health of the body and brain:
When you loose the ability to accommodate the ciliary muscle in the eye for focused vision (near or far), you loose your primary ability of adapting to different life conditions as well, meaning no life pulsation and life fades away. It seems, adaptation of the human body to the surrounding world is heavily controlled by accommodation in the Eye.

ALL IN ALL, the work by Drs. Hollwich and Prentice a.o. shows that the influence between the Eyes and the neuroendocrine systems of the body and brain goes both ways. The brain is the regulator, but primary stimulation and synchronization comes by means of the eyes, so ocular light has a profound influence on health.

In practice, the Eye Lens is a very important media in controlling ocular light transmission and stimulation of the nervous and endocrine systems.

The research of Dr. Hollwich was carried out on old people with very mature cataracts and a remaining light transmission of less than 10%. As these people were old, it is assumed their brain glands (hypothalamus, pituitary, pineal) were somewhat sluggish and hypofunctioning on a reduced pace. Also, it is to be assumed, that many of these cases were not "originally myopic". In these cases, it seems natural to restore the central ocular light pathways to the brain glands via the RHT to a maximum extent (meaning 0D, plano, or maybe slightly myopic) to sympathetically stimulate the hypofunctioning brain glands of these older individuals allowing the control centres to function at a normal pace.
In younger individuals, however, and especially those with a hyperfunctioning brain and nervous system disorders (and "originally myopic" individals), it seems more reasonable to transfer less light stimuli through the sympathetic central ocular light pathways allowing for the control centres of the body, the brain glands, to function at a normal pace (confirming the work of Dr. Prentice).

With glasses (minus lenses) the myopic individual can change from a parasympathetic basis condition to a sympathetic condition, if we need it. We just need the basic condition, the foundation, to be parasympathetic, because it is in the parasympathetic mode, we sleep and relax. Without parasympathetic dominance, there is no sleep, so being stuck in the sympathetic mode is terrible, it allows no relaxation and no healing. Like this, in cases of lost adaptation to the surrounding world by the sympathetic and parasympathetic divisions of the ANS, e.g. due to brain glands problems, then glasses and contact lenses can be used as substitutes for the lost ANS mode by accommodating to the lost vision mode (far or near). Therefore, we can conclude, there is a clear link from eye accommodation to whole body adaptation to life!

Also, other sensory organs of the human body have several tasks. E.g. the mouth, besides taste (information) takes in energy with the food. Besides smell (information), we also take in air and energy through the nose, so why not expect the eyes to house several tasks; that is, to take in not only information for normal vision, but also light energy for electrical functions throughout the nervous system and cells of the body?

Actually, 2/3 of the necessary energy supply to the CNS comes from the two retinae, and 98% of sunlight enters the body through the eyes (being the body's primary acupuncture points, leaving 2% to enter through other acupuncture points on the skin). The total blood volume of the body passes through the eyes in less than 40 minutes, and only in the eyes is the blood exposed directly to the full visible spectrum of electromagnetic quantum energies. Contrary to acupuncture points later in the body circuit, eyes are before the brain in the body's energy circuit flowing from top to bottom, thus stimulating the brain - and the three light sensitive brain glands - highly. 90% of the sensory information coming to a person through a lifetime enters as ocular light. Also, functions related to eyesight take up more than one third of the grey matter in the brain, and added to these normal, conscious seeing functions through the visual cortex (here), important energetic, unconscious seeing functions for autonomic, vegetative functioning have central positions in the brain in the light sensitive brain glands of the Hypothalamus, Hypophysis and Pineal gland (here and here). Eyes are superior to the other senses, shown by the fact that when collecting or constructing memories from the other senses, eyes are involved (here, p.19-20).