The effect of coloured transparencies on the reading performance of reading-disabled children

Abstract
The effects of coloured transparencies on the reading ability of specific reading‐disabled (SRD) children were investigated. Irlen (1983) claimed that SRDs suffer from an over‐sensitivity to light of certain frequencies, and that, with the use of coloured lenses, this over‐sensitivity is ameliorated, resulting in immediate improvements in visual processing. The present experiment attempted to measure such improvements on two different types of tasks ‐ a reading task and a reading‐like letter‐identification task. Eleven experimental and 11 control subjects were selected according to the standard criteria. The reading task involved reading three passages in the pre‐test then reading the same three passages in the post‐test but with the aid of either plain frames, polaroid (placebo) lenses or individually selected coloured transparencies. The results of these tests indicated that there was a practice effect, but no placebo effect nor any improvement due to the coloured transparencies. In the letter‐identification task the subject was required to recognise a randomly chosen letter, presented randomly in any one of 15 positions across the visual field. The same three viewing conditions were used. Again, there was no placebo effect nor any effect due to the chosen coloured transparencies.