ADD / ADHD, Science, Visual

Left blind-spot ‘gives ADHD clue’

Stand up and look straight ahead. Without moving your eyes, use your peripheral vision to become aware what furniture or people are on your left and your right. Now imagine that you are unaware of what is on your left. Not that you can’t see or hear them but that you have no concept of their existence. It can’t be done consciously but this is one of the harder to comprehend effects of a stroke or brain damage and is known as hemispatial neglect. (You can sit down now). This strange phenomena leaves the patient unaware of anything on their left and can result in patients only eating food on the right-hand side of the plate. This isn’t blindness, the visual signals reach the brain, it is just that different parts of the brain are not functioning together. It is a problem that is hard to understand, almost impossible to treat and raises questions about what is consciousness.
Now a cluster of new studies led by Dr Tom Manly of the Cognition and Brain Sciences Unit at Cambridge has looked at hemispatial neglect in people with ADHD. The found that is was more widespread than had ever been considered. During boring or repetitive task the right brain, which deals with vision from the left eye, simply switches off. Even in normal children this happens after about 40 minutes but in ADHD it happens more often. This can cause reading problems as the child misses the first letter or two of the word. It would also cause clumsiness and inattention / misbehavior. A child isn’t going to obey an instruction if they are not aware of the parent even being there.
I wonder how this relates to your general field of vision as from my own experience a dyslexic can have a very narrow field of vision.

See also: New Clues to Understanding Attention Deficit Hyperactivity Disorder in Children, Left blind-spot ‘gives ADHD clue’

Abstracts:
Examining the relationship between rightward visuo-spatial bias and poor attention within the normal child population using a brief screening task

Asymmetric deterioration of spatial awareness with diminishing levels of alertness in normal children and children with ADHD

Spatial awareness, alertness, and ADHD: the re-emergence of unilateral neglect with time-on-task.