An Eyelink-2 head-mounted eye-tracker was used to record the eye-movements in reading of 63 relatively high-functioning, self-referring dyslexics. They read 5000 words of newspaper text that we have previously used to study the reading behaviours of more typical English readers. The precise spatial and temporal aspects of the reading behaviours were recorded for the dyslexics and a range of language tests and tests of cognitive ability were also run to allow us to characterise the wider abilities of the dyslexics.
We recorded the eye-movements of 63 dyslexics as they read a corpus of 5,000 words of text from newspaper stories. We profiled these self-referring dyslexics on a set of measures of linguistic and cognitive abilities, enabling us to compare them with other studies of dyslexics. Their reading behaviours can be compared against those of 36 typical English readers of a similar age and background, recorded in our own laboratory using the same apparatus and procedures. Critically, the movements of both eyes were recorded, enabling us to interpret the results in terms of our own published theory of binocularity in reading.
The dyslexics made more and longer fixations, and some of them made more regressive fixations, compared with the typical readers.
Dyslexic and typical readers behaved comparably in that the final binocular disparity within a fixation was about 90% of the initial disparity.
We have concentrated on exploring the movements of the two eyes within fixations. We have discovered that in dyslexics there are more directionally variable horizontal movements, particularly left-to-right ones, compared with more typical readers, and beginning from a more leftward position within the word. Dyslexic reader, particularly males, move their left eye more variably. This variability is interpretable within our own hemisphere-based analysis of eye-movements in reading.
We have also demonstrated precise coordination between the two eyes in the first published eye-tracking of an individual with Douane's Syndrome, in which the left eye is inhibited from moving to the left of the middle of the page.
|Effective start/end date||1/12/09 → 30/11/10|