Home I Contact I Search
0. Left & Right Brain
1. Masking Alpha Channel
2. Rods & Cones
3. LGN: Magno & Parvo
4. SC: Superior Colliculus
5. Primary Visual Cortex
6. Dorsal - Ventral Stream
7. Eye Movements
8. Oculomotor System
9. Balance System
10. Ectopia & Microgyrus
11. Genetic Etiology
12. Reading
13. Animals
14. Conclusion / Solution
15. Different Theories
16. Peace of Mind
… and in this way our eyes creates alignment where our view crosses over from non covered, less-sensitive to covered sensitive areas. This way we have a cross-over area/line that can be seen as a linear and/or volumetric marker. (link)


 While observing top-sportsmen I noticed that they had similar facial characteristics; eyes more significantly surrounded by masking/aligning elements.


I simulated this by simply laying a finger on the intersection between my eyes and just looked around to see what influence this had on my sight. The result for me as a dyslectic was quite significant: my view was more balanced, I could look at a subject without the extra concentration. This was something interesting so I started a quest into the world of sight and dyslexia.

This site is build up out of different sections:

A. Left & Right Brain interaction

B. Exterior elements of our visual system

C. Interior elements of our visual system

D. Dyslexia

E. Reading

F. Animals

G. Conclusion

H. Dyslexia Advice



0.1 Left and Right Brain: function & interaction

 A good understanding of how the interaction between our brain halves work is crucial. Both brain halves process their input differently: one side thinks and sees in wide-angle (S) while the other zooms in on the detail (F). Researchers have come to see the distinction between the two hemispheres as a subtle one of processing style, with every mental faculty shared across the brain, and each side contributing in a complementary, not exclusive, fashion. A smart brain became one that simultaneously grasped both the foreground and the background of the moment. (more)

 0.3 Ocular Dominance 

Ocular Dominance is the tendency to prefer visual input from one eye to the other, like right or left handedness. In binocular vision there is an effect of Parallax and therefore the dominant eye is the one that is primarily relied on for precise positional information. Focus can change from the right eye (detail) to the left eye (global).


When aiming at a target, we close one eye to form a direct line with the target. When we read, the target isn't a solid object but a group of interacting letters (details), we have to make visual focal balancing steps to interpret text. (more)

0.4 Shifting Dominance 

 There are 3 descriptions of dominance, and it is possible that the dominance for a person may shift between left- and right eye depending on the type of focus. In nature our visual system is based upon a 3-dimensional space but when it comes to reading our view is focused on a flat, no-depth environment, with small detailed words. A reader has to reduce his/her peripheral-view and shut him/herself off their environment full of sounds, colors, shapes, movement.


A person with a weaker 'visual-alignment-system', cannot get grip on the text elements, and start to over-focus with one eye to get a hold on the detailed word (right eye), or on the global text (left eye). It also might cause them to shift their natural dominance from left to right. This 'over-focusing' stops the naturally 'flow', the ocular dominance system can get out of balance, unnaturally shifting dominance from detail to global creating visual disturbances and a blurry sight. (more)

0.5 Left and right brain: Language processing 

 The main difference between Left Hemisphere (LH) and Right Hemisphere (RH) can be found at the micro-anatomical level. There are numerous asymmetries that influence how neurons spread information. At the cellular level, pyramidal cell dendrites branch further from the soma and ultimately into more branches with more dendritic spines, in the RH than in the LH.

Such circuitry favors more input from relatively distant sources in the RH, and from close sources in the LH. Thus, cortical mini-columns, macro-columns, and functional areas are more highly overlapping and more densely interconnected in the RH than in the LH. Because functional and structural levels of brain organization are interdependent, some effects at each level get passed through to higher levels. (more)

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1.2 Eye Movement & Facial Masking elements

The first ideas I had was that the masking intersection between our eyes defines visual balance. As a test, I made a simulation of a moving object with different intersections. The captured images where combined, as a result: the intersection level can influence a fluent transition from one eye to the other; it can help establish a 'sharp-focus' by reducing blur, it can be a significant aid for visual alignment, and at sports where there is a high level of tracking needed the right amount of masking can be helpful. And in contrast for dyslexics, who have a more sensitive peripheral view and a not so strong Visual Grid, the elements of 'Blur' or 'Gap' can be highly disturbing to read. and a not so strong

 But in case of 'causing' dyslexia; people with all levels of intersection usually don't have any problem with 'reading', so this idea that the intersection works as a switch to change from one view is to simplified. This test also doesn't include the knowledge from other topics such as Ocular Dominance and Left and Right Brain, that explain how our eyes look in a different way; Left-eye more 'Global', and Right-eye more 'Detailed'. (more)

 1.4 Asians have Horizontal Masking & Aligning regions (Alpha-Area)

An other question I had is; how asians who often haven't got a noticeable vertical intersection can align? Asians have view masking close to their eyes in a horizontal and often oblique way, created by the eyelids, giving them a horizontal alignment system similar to the vertical intersection for occidentals. There is an interesting article in National Geographic about this subject: "Chinese, Americans Truly See Differently". (more)

 1.5 Different alignment gives a different view

Alignment is the adjustment of an object in relation with other objects. Our view is aligned to the facial elements that surrounds our eyes, for Asians this alignment is horizontal as they haven't got the signature intersection like occidentals, who have a vertical alignment.


 Horizontal alignment represented by the stripes on the image is used by asians as a 'hold-on' to move over the picture. He/she will start at the tip of the boat on the left and will automatically go to the right to get immediately a full impression of the boat, he/she will move on to the boat in the back and on to the left of the visual field passing by the mountain in the far back, on to the wave that's going to crush the boat, creating a spiral movement that explains the story in one fluent motion. (more)


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 Overview of the visual pathways:

Light fall's into our eyes and is projected through the lens' on rod- & cone cells in the retina. The information of these cells is collected by ganglion & bipolar cells  and is send on through a relay mechanism called the LGN and the SC on to the first visual part of our brain called the Primary Visual Cortex.

 2.2 Rods, Cones, Facial Masking & Alignment (Alpha)

The facial masking structure that surrounds our eyes and the structure of the retina (rods & cones) has interesting correlations. Key points of where the eyes get in contact, or lose contact with the nasal intersection, they correspond to bumps in the diagram where the percentage of rods take a drop.


Key points work as thresholds aligning and locking our view. The bumps are situated in the peripheral rods-fields of the retina, an area that defines contrast and movement, important for reading. (more)

 5. Primary Visual Cortex (V1)

Binocular view is represented in the primary visual cortex of the brain as a striped pattern, the blank triangular area represents monocular view (MC). The MC region is defined by facial masking elements that surround our eyes, the more masking there is, the lesser peripheral-binocular input our brain has to process. A theory based on; striped pattern minimizes the length of neuronal connections, explains the function of the striped patterns. (more)

5.2 Visual Grid and the Origin of Patterns in V1

The Striped pattern is an evolution of making the shortest and fastest connections between visual input of both eyes.

 V1 Creates a visual grid so we can stay in balance and have grip on our environment. We find visual alignment and hold-ons in vertical and horizontal lines in our environment, giving us a structure so our view can find balance. (more) 

 5.4 Facial Masking Alpha in Primary Visual Cortex (V1)

Two eyes focus at one point while masking is increased. On the diagram we can see the influence of different masking levels on the primary visual cortices.


Result: a larger masking elements reduces visual noise and peripheral distractions. and our brain has to make less peripheral-connections, making it easier to focus and concentrate on objects in our frontal view. This is very beneficial for reading, and the increased masking region (alpha-area) also provide a more present alignment structure. (more)



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For some dyslexics it is a matter of a weak visual alignment system:

Defaults in the LGN causes for a weak alignment. A reader has a weaker grip on horizontal and vertical lines who are detected by peripheral rod-cells of the retina (eye), and processed by the smaller Magnocellular-layers of the LGN (relay system), onto the primary visual cortex (image processing) that has a preference to 'lock-on' to vertical and horizontal lines.


1. The Retina: Rods and Cones
2. Magno and Parvo in the LGN
3. Visual Grid and the Origin of Ocular Dominance Patterns in V1
4. Different alignment gives a different view

I. Professor Albert Galaburda and his research team at the Harvard Medical School discovered in dyslexic brains:

a. Differences in the LGN.

b. Language centers that showed microscopic flaws known as Ectopias and Microgyria.

c. A more symmetric Plana Temporale.


ll. An other recent study shows that variations in a gene called DCDC2 may disrupt the normal formation of brain circuits that are necessary for fluent reading, leading to dyslexia.

“We have good statistical data that variations of the DCDC2 gene are strongly associated with reading disability, also known as dyslexia. These results reconfirm that dyslexia is strongly genetic and is not a consequence of just environmental factors,” says lead investigator Jeffrey Gruen, M.D., Associate Professor of Pediatrics at Yale University School of Medicine. (more)

 3.2 Dyslexia and LGN

A study published in 1991 by Harvard Medical School researchers reports of a post-mortem study of people with dyslexia and found differences in their LGN. They looked at the subdivision of the LGN and found that the cells in the M-pathway are smaller in people with dyslexia.

The M-pathway processes the visual information collected by the Rods-cells in the eye's Retina and sends these signals on to the primary visual cortex (V1) in the back of our brain.


5.3 Dyslexia and the Primary Visual Cortex (V1)

A smaller M-pathway in the LGN leads to a different processing of information from the eye's Retina on to the Primary Visual Cortex (V1) in the back of our brain. 


Result: A less filtered input-stream of Motion and Orientation makes it harder for dyslexics to have a steady view, less visual grip, and a weaker alignment system. (more)

 3.3 Monocular Occlusion

"The Magnocellular Theory of Developmental Dyslexia" publication of Professor John Stein of Oxford University, covers many topics including monocular occlusion where-in he writes:

  • "…abnormal magnocellular function may cause such binocular instability."
  • "…blanking the vision of one eye can simplify the visual confusion…"

Result: These topics correspondent to my experience of increasing facial masking by laying a finger between my eyes, giving me visual balance, and by doing so the peripheral view of both eyes is decreased, reducing the input for the M-pathway of the LGN. (more)

 4. Superior Colliculus (SC)

Parallel with the LGN are the Superior (SC) and Inferior Colliculi (IC), they are 2 pairs known collectively as the Corpora Quadrigemina (Latin: quadruplet bodies). The CQ receives visual as well as auditory inputs in its layers, who are connected to many sensorimotor areas of the brain. The CQ as a whole is there to orient our head and eyes to what we see and hear.

  • The superior colliculus: Visual processing, control of eye movements.
  • The inferior colliculus: Auditory processing.

The SC is an important link in the visual brain streams transmitted from V1 and controls the extra-ocular muscles that direct gaze needed for al the different types of eye movements as saccades. The SC works with the sensory system that provides the input for movement and orientation in space and is linked with the Auditory-system to keep our balance.

This system works like a chain, where a deficit in one part can effect the other elements. For dyslexics, a differentiating LGN linked to SC and IC can cause enough deviation to withdraw the eyes from staying focused on text. It also can effect the hearing system where many dyslexics fail to develop adequate phonological skills (more).

 10.1 Ectopia & Microgyrus

An other element that Albert Galaburda and Thomas Kemper found from examining dyslexics brain were clusters of ectopic neurons in the outside layer of the cerebral neocortex. This layer usually is devoid of nerve cell bodies, most ectopias were found in the Frontal and Perisylvian language regions, they are produced before six months of gestation when there is a breach in the Pial-Glial border which normally prevents neurons from migrating too far. (more)


Scientists recently identified a risk haplotype (a genetic constitution of an individual chromosome) associated with dyslexia. Their data suggest a direct link between a specific genetic background and a biological mechanism leading to the development of dyslexia. (more)

11.2 Pressure Phosphene

It is known that in fetal-development by the end of the 6th month, the eyelids begin to part and the eyes open, and the baby may respond to sounds by moving or increasing the pulse, this corresponds to the areas where dyslexics are disadvantaged.

 Could Pressure Phosphenes be one of the "biological mechanism" that causes these Ectopias? Pressure phosphenes appear at the peripheral areas of our sight, analog to the M-pathway of the LGN. Ectopias are produced before 6 months of gestation when there is a breach in the Pial-Glial border which normally prevents neurons from migrating too far. Eyes that are shallow may be more sensitive to pressures in the womb and in combination with rapid eye movements, could lead to Pressure Phosphenes giving strong pulses to the LGN and on to creating Ectopias. (more)

11.3 DCDC2 & Dyslexia

A recent study shows that variations in a gene called DCDC2 may disrupt the normal formation of brain circuits that are necessary for fluent reading, leading to dyslexia.

In humans, the DCDC2 gene is strongly expressed in the same brain regions (cortex, hypothalamus, amygdala and hippocampus) of normal and dyslexic readers, suggesting that changes in the gene's function, rather than a deletion of the entire gene, cause the disorder. The gene in people with dyslexia is altered but still somewhat functional, which may explain why dyslexia is frequently associated with subtle changes and not extreme learning disability. (more)


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 12.1 Normal image processing / Reading

When it comes to reading: 1. The right eye sees a point (detail) and the left eye sees the relation to a line (global), 2. The right eye sees this line and the left eye sees it's relation to a letter, 3. The right eye sees the letter and the left eye sees the relation to a word, and finally we read a whole sentence. Our eyes constantly combine detail and global. (more)

 12.2 Dyslexics and Image Processing / Reading
Dyslexics who have an anomaly in their LGN, can experience trouble getting grip on the text they try to read. In combination with different levels of visual-masking, a weak visual grid can have different implications:

  • Small masking region: Less alignment and a broad peripheral view relevant to the focus distance for reading text (detail). This enhances the lack of grip and shifting dominance giving a Blurred view.
  • Large masking region: A Gap disturbs the natural balancing process of combining the view of both eyes, detailed (right) and global (left). (more)

12.6 Alignment and Text in Different Cultures

  •  The Alphabet has a vertical-lines-pattern: I I I I I I I I. Note: when the letters are turned we start to move our head, to keep our visual grid aligned, until they are vertical.
  • Chinese script is conform to their tendency for horizontal alignment, written in a vertical direction. An interesting article in National Geographic: Chinese, Americans Truly See Differently, Study Says 
  •  Arab script the spacing between the vertical alignment elements is wider —.—I—.—I—. The baseline is often much bolder to keep create a strong alignment. (more)


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13.1 Animals Overview

Evolution adapted the eyes of different species to different types of environments. There are Nocturnal, Diurnal and arrhythmic types and each type has their predators and prey animals. Nocturnal animals have big lenses and a small Vitreous Humor, their eyes work as a sensor for movement in the dark and mainly use rod-type cells for night vision. A large lens also converges more light and gives a brighter image.

Pupils contract when more focus is needed, in contrast to the passive view blocking areas that surround the eyes, although the eyebrows can be frowned and eyelids can be narrowed to increase masking.

Cats, who have to keep track of fast moving objects like mice, narrow their pupils into a vertical-line shape, sharpening their alignment system. (more)



13.2 Deer have 90° clockwise turning eyes

 Deer have pupils in the shape of a horizontal ellipse, to have a horizontal alignment with their environment. When they graze, they turn their eyes 90° clockwise, to keep their view horizontally aligned. They also lift their eyebrows to keep their eyelashes horizontally aligned using them as an alignment in conjunction with their pupils. (more)

 13.3 Frogs & Toads

The pupils of Frogs & Toads come in all kinds of shapes, there is even a group with Heart-Shaped pupils, this group is interesting when it come to alignment, when we closely look at the skin-pattern of 'Oriental fire-bellied Toads' we can see that they have direction lines on the front of their beak, this flames-pattern works as a watch-like alignment system that helps as a hold-on for them to track fast moving insects. (more)



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14.1 Conclusion / Solution

The facial masking region can be considered as an important influence on our viewing process, because it gives alignment and defines the amount of peripheral view the LGN and V1 has to process.


 Dyslexics with sensitive peripheral-view and thus a weaker 'Alignment system' can be helped by reducing their peripheral view, getting a stronger 'Visual Grid', and reducing visual stress, like in my case and starting point of this whole research, by using my finger to increase the intersection between my eyes. As a solution; a simple frame, increases the masking-regions and thus reduces peripheral view. It also gives extra alignment, and this can be an aid for reading. But this can conlfict with the way you are normaly used to see, so acceptance of your view, with it's pro's and con's might be the best thing to do. (more)

14.2 Physical & Psychological effects of adjustment of peripheral view.

Having a stronger Visual Grid, by peripheral-view reduction, changes the visual-input-stream and influences how the brain works. A clearer input stream from the Primary Visual Cortex in the back of the brain on to the frontal processing areas, gives a more precise way of seeing and can speed up visual processing. It can also result in a more refined sense of visual control, for older dyslexics this can lead to a reduction of visual stress activating the hippocampus, changing serotonin levels and leading to a mild form of euforia. This 'new view' can conflict with the way someone is used to see; a clear sharp-view vs. the old stessed vague-sensitive-touching way of seeing, it can even cause a shift in visual dominance. Physically one can hold his/her head in a different way as he/she has more visual grip on his/her surroundings. (more)

14.3 Vision Therapy

I got this reaction from the College of Optometrists in Vision Development:

"… In much the same way you discovered the 'masking' helped you, we use both bi-nasal occluders on glasses and small amounts of base-in prism to reduce peripheral "overload" in patients. Dr. John Streff has written quite a lot about these effects, particularly in helping head injured patients. You may want to find and read some of his papers."

As for now I haven't yet put a lot of time in reviewing Dr. Streff's research but it indeed seems to correlate with my experiences. (more)

16. Peace of mind

 A natural way to overcome the problems that go together with a sensitive peripheral-view, is to do exercises to find peace of mind and reduce the effects of visual stress. The stress of not getting grip on text often causes even more stress, by letting go of focusing to hard and rather just flow (gaze) over the text, one can improve his/her reading-skills, this is also a more natural way of coping with dyslexia, some of these exercises are:

  • Visualization of an imaginary focus-point, where the reader focus' beyond or before the text, creating a more gazing approach towards the text itself. This way the reader stops to over-focusing and has a more sensing and vague approach, allowing him/her to flow over the text.
  • Body movement when juggling one learns to focus on the global-ball-movement and not staying focused on one ball. This way he/she learns to create a rhythmic flow without staying focused on one particular detail such as a letters or word, and go to the next text line.
  • The use of colors, separate parts of text are written in different colors. Colors aren't based upon alignment, this way a dyslectic can train to follow a reading rhythm, flow.

Understanding of how a dyslexic thinks makes it more acceptable for his social environment. A good book on this subject is by Professor Bob Frank: Secret Life of the Dyslexic Child: How She Thinks. How He Feels. How They Can Succeed. (more)

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I sometimes get emails from people who look for help, such as this mother who's child has trouble with 'reading' therefore this small topic, with a word of advice. (more)
Comments are welcome at: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

If you are new to the subject of Eye-movement, Retina, LGN, Primary Visual Cortex (V1), etc., there is a very informative site: "The Physiology of the Senses Transformations for Perception and Action" from Professor Tutis Vilis from the University of Western Ontario, that has nice flash presentations about these subjects, they can also be downloaded in the pdf-format. link:


The purpose of this site is to present questions and new ideas about the above subjects.

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