Still No Evidence for a Photoreceptor-Level Abnormality in Dyslexia

Abstract

In reply to Grosser and Spafford's (1992) defence of their theory that there is a photoreceptor-level abnormality in dyslexia we argue that (1) their original experiments do not tap rod functions, (2) the theory fails at the quantitative level, and (3) the proposition that rod inputs generate transient responses is false.

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