The Visual System and Neuroimmunity – Part 2


I introduced you to Michal Schwartz in Part 1, and her work clearly supports some strong points we’ve been making on our visionhelp blog for quite some time to counteract medical dogma.  One of the major points is that the eye and brain are inseparable in terms of function and, in part, this stems from the fact that the retina does a considerable amount of pre-processing of information prior to sharing visual information with visual processing streams throughout the rest of the brain.  It is really high time for critics of vision therapy saying that “you’re overstepping your bounds because these are brain problems you’re dealing with, not eye problems” to let it go, and appreciate the eye as an intimate part of the central nervous system and the outermost part of the brain.

Repeat after me: The eye is part of the brain … the eye is part of the brain … the eye is part of the brain.  There now, doesn’t that feel better?  It’s really quite simple.  The eye is a necessary but not sufficient part of the visual process.

Professor Schwartz makes this point forcefully and beautifully in her new book, Neuroimmunity on p.113, where she demonstrates that the retina is a continuous part of the brain.  This leads her to the following conclusion:  “Although anatomists consider the eye as an extension of the brain, modern medicine in the West has dealt with the organ as if it were a separate entity.”

Schwartz Book

FullSizeRender-167

Professor Schwartz’s revolutionary focus has been on glaucoma, and showing how damage to the optic nerve and neurosensory retina is really a secondary degeneration due to a self-perpetuating cascade, or domino effect of free radicals and unbalanced neurotransmitters resulting in toxicity common to all neurodegenerative conditions of the central nervous system.  Although this has shifted the paradigm in glaucoma, it has yet to be appreciated for its impact on other aspects of the visual system, the most obvious being in cases concussion and trauma associated with mTBI.  Professor Schwartz’s focus on repair has been the development of a vaccine approach not in the conventional way we think of childhood vaccines, but to promote a balanced immune response that stops the domino effect and reduces further death of neurons.

FullSizeRender-169

Clearly there are other ways to boost the immune system and brain function, not the least of which is immune-boosting foods. Neuroimmunity and its influence on the CNS, brain, eye and visual system has its roots in the field of pyschoneuroimmunology.  Steve Cool lectured at a COVD meeting on the subject about 20 years ago, and prior to that Elliot Forrest made some of these linkages in his COVD lecture about Canon and Selye, and in his book on visual stress.  Most recently, Merrill Bowan has alluded to this in terms of the role of dopamine neurotransmitter balance in response to lenses, prisms, and vision therapy.

10 thoughts on “The Visual System and Neuroimmunity – Part 2

  1. From ‘Visual Perception: A Clinical Orientation, 4th Ed.’, Steven H. Schwartz, McGraw-Hill – “Retinal midget (parvo) and parasol (magno) ganglion cells manifest properties similar to their counterparts in the LGN.” So, while you are correct that brain is eye, eye is brain, strictly speaking, the eye itself is not limited to the globe, but terminates deep in the brain, at the thalamus. Even then, there is good reason to postulate that the LGN itself is another ‘eye organ’, the end of the line if you wish. Here’s the thing: Pediatric ophthalmologists view strabismus as primarily an issue of poorly executed EOM genesis (and some still feel the ‘muscles are too week’), and so they work on muscles. They have no interest in efferent or afferent processes driving vision, so if VTOD’s are forbidden to address vision beyond the eye, then NO clinician would be paying attention to the largest component of vision, the cortical and subcortical part.

    Thanks for the post.

  2. You’re welcome, Charles. Thanks for the added insights. I am equating the eye to the contents of the eyeball. I look at the optic disk/cup/rim as the posterior-most part of the eye, and the optic nerve as the fiber optic cable that communicates information from the neurosensory retina to the rest of the brain. I have a tough time conceptualizing LGN as another eye organ. It seems to be a structure serving more as a conduit and as a sensory mixmaster that influences what arrives in the occipital lobe, than as an extension of the eye itself. If we accept the LGN itself as an eye organ, then why not the occipital lobe an eye organ?

    • ” If we accept the LGN itself as an eye organ, then why not the occipital lobe an eye organ?” – If you look at retinal neurology/neurophysiology, there is no distinction between retina (part of it) and optic nerve. Histological studies show LGN cellular properties are near identical to elements of the retina, while there is virtually no similarity between retinal/LGN cellular structure/function, and that found in cortex. That’s why I could postulate the eye ends there, at the LGN. Yes, distinct structures, but upon closer examination, not so separate. No question, eye is brain. “Mixmaster” is a rough term, but clearly the LGN serves afferent and efferent signalling and signal processing, not simply a train station where visual impulses are passed along downstream. LGN, like all other thalamic nuclei, are heavily implicated in gathering and processing sensory (afferent) and cortical (efferent) inputs, sensory integration, attention, and volition. In my understanding to this point that we might consider the thalamus as the centre of our ‘egos’ (aka ‘consciousness’): Our invisible selves hovering in a void somewhere behind the eyes and between the ears where all of our senses intermingle, and from where we launch motor planning and responses. The thalamus itself is located precisely in that spot, straddling the third ventricle. If the brain had the array of somatoreceptors enjoyed by our skin and internal organs, we would literally ‘feel’ our thalamic nuclei chugging along, perhaps akin to muscle strain, or pressure, depending on context, of course. My guess. Using Wikipedia for expediency only: https://en.wikipedia.org/wiki/Thalamus

  3. Excellent point about the anatomy of the LGN being more compatible with the retina than the cortex, but the eye is the eye, and the LGN is an intimate hot spot for bidirectional communication between cortex and moving the eyeball to locate and sense. Never implied that the LGN is simply a train station — as noted above, it the arbiter of what is communicated with cortex. Your suggestion is a bit like Crick & Koch in suggesting that the thalamus is the egocenter/aka consciousness. That was their “astonishing hypothesis”, which seems to have astonished them alot more than other people (even their buzz phrase of the quest for the neural correlates of consciousness has seemingly died). Hence the quest of consciousness is still very much on. I don’t think we’ll ever find a structure that we can touch and wiggle consciousness as we do our ears. In any event, I’ll give a bit more thought to LGN as the posterior of the eye, though regarding retrobulbar space as part of the eye then sets up the parallel challenge as the thalamus as part of the ear, doesn’t it?

  4. ‘thalamus as part of the ear’, no, the MGN would be if we follow the same line of thinking. Agree that consciousness is more broadly spread than simply the thalamus, but given the structure, it would certainly play a key role in integrative processing. At any rate, good thread, Len.

  5. Len, while both LGN and MGN are part of the thalamus, they are distinct nuclei. So to say ‘MGN is part of the ear’ is equivalent to saying ‘LGN is part of the eye’. This is very different from asserting the ‘thalamus is part of the ear’. Since the thalamus is the collection of nuclei, and not the individual component nuclei themselves, saying ‘thalamus is part of the ear’ is too generalised to be accurate. Given the integrated nature of audition and vision, meaning the various inputs/outputs, we could more easily argue that ‘thalamus plays an integral role in both auditory and visual processing’, so thalamus is a part of audition, but also a part of vision, and so on.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s