Magnocellular Processing, Attention and Reading

Our recent research has suggested that visual magnocellular (MC-) activity plays an important role in reading and that MC- deficits contribute to reading problems because the MC -system plays an important role in directing visual attention and eye movements to letter and word features. So we have been studying the relationship between MC- processing, attention, and reading in over 50 children from primary schools around Oxford.

The children were shown four patches of randomly moving dots designed to selectively stimulate the MC- system. In one of the patches there was a specific pattern of motion which the children were asked to identify. Before each trial a hint was given as to which patch was going to show the motion; but sometimes the hint was incorrect. This directed attention towards or away from the correct location.

Good readers benefitted greatly from the correct hints and were correspondingly worse off after the incorrect ones. But the poor readers were helped less by having their attention drawn towards the correct location of motion, and less hindered by having it directed away from it. Thus poor readers seem to suffer from slowed visual direction of attention that is probably due to weak visual magnocellular performance.

This impaired direction of visual attention makes it slower and harder for them to determine the correct location and features of letters and words. We think that poor readers may also suffer a similar problem with attending to the auditory order of sounds in words.

Read 'The Magnocellular Theory of Developmental Dyslexia' paper here

Read ' Fact sheet: Outcome of Treatment on visual problems in children with reading difficulties' (.pdf format)