Helen Irlen, an Educational Psychologist, first identified Scotopic Sensitivity Syndrome/Irlen Syndrome in 1981 whilst working with undergraduate students with reading and learning disabilities. She observed that a number of the students had a significant improvement in their reading ability when coloured plastic overlays were placed over printed material.
The coloured overlay or filters are reported to minimise print distortions when an individual reads and writes. Irlen lenses may therefore improve reading comfort, speed, comprehension and duration, and reduce strain, fatigue, migraine, headaches and glare.
One group of studies have reported improvements in reading when using coloured plastic overlays or coloured computer monitors (see Jeanes, Busby, Martin, Lewis, Stevenson, Pointon et al., 1997; Tyrrell, Holland, Dennis, & Wilkins, 1995; Williams, LeCluyse, & Rock-Faucheux, 1992). Another group of studies have reported improvements in reading with the use of coloured lenses (see Irlen & Robinson, 1996; Robinson & Foreman, 1999; Solan, Ficarra, Brannan, & Rucker, 1998).
Source: Centre for Special Education and Disability Studies (2002)
Irlen lenses may improve visual perception but it does not develop or improve spelling, grammar, or knowledge. These deficit's in learning need to be attended to by individual tutoring.
The development of the skills of written language may be impeded by poor visual perception, but improved perception will not improve the skills themselves. These must be learnt, and, where inappropriate strategies have developed, these must be unlearned.
Source: Whiting, P. (1994)
For further information refer to: