Opening Eyes to Learning Difficulties
Learning difficulty and disability has long been a problem for many children, parents and school teachers alike. Dysfunctions such as dyslexia and motor disability have hindered the progress of countless adolescents across the country and continue to do so with every passing day. Now, studies have been performed that may centralize learning difficulties to the eye, rather than the brain itself.
Researchers at the Norwegian University of Science and Technology are conducting research that creates a causal link between motor and learning disabilities and dysfunction in visual perception. For example, people who cannot quickly learn a simple motor task such as catching a ball may have difficulty because the cells in their eyes are not perceiving the stimulus properly. The same rings true in individuals with dyslexia – their eyes may not be correctly processing the visual stimuli of words on the page.
The ocular cells in contest here are deemed “magno cells” and detect rapid movements in our visual field, creating the movie-like perception we experience on a daily basis. Without these, life would look like a disconnected string of frames – much like a comic book. In a test conducted by the researchers, it was found that individuals with difficulty in mathematics also showed difficulty in tracking the randomized movement of a dot on a screen with their eyes, elucidating a link between eye function efficiency, detection of rapid changes in the environment and learning ability.
In a greater context, this finding may have implications in special education and may change the mindset of those working with individuals with additional learning needs. With this new information, learning disability can be combated from the angle of visual field perception. Techniques aiming to strengthen visual perception and eye efficiency (such as eye movement and tracking exercises) could act as a therapy for learning or motor disability previously thought to be localized in the brain itself.
Source: Science Daily via The Norwegian University of Science and Technology
July 8, 2010
If retinal cells are at fault in diseases like dyslexia (there is evidence that dyslexia is a problem in rapid processing in other parts of the brain), is the problem any simpler than if the defective cells were from another part of the brain (say, auditory cortex)?
And just because kids who have difficulty with math also have problems tracking dot movements, no one can claim that the math difficulty arises from inefficient magno cells (causation).
July 8, 2010
No, the problem actually becomes more complex. Given that there may be malfunction in the retinal cells, the incoming information stream could be distorted before it even gets to the LGN/thalamus and the higher brain, where there may be further deficits in processing. This complicates everything and creates the hypothesis that learning disability arises from a combination of malfunction in perception and processing, and that the brain may be incorrectly processing already distorted input.
Also, the claim is not that deficient magno cells are causing difficulty in mathematics. It was just a manifestation of the theory that inefficient perception is correlated with learning difficulty. The test could have easily been performed with dyslexics or kids with motor control problems instead of with math tests – they are just inherently easier to score and measure. However, I think much further study is indeed needed to try and bridge visual perception inefficeincy with specific learning deficits and correlate that information with actual brain function abnormality.
The eyes have only added another variable to an already immensely complex equation.