S. Heath|Dorothy V. M. Bishop|John Hogben|Neil W. Roach
Psychophysical indices of perceptual functioning in dyslexia: A psychometric analysis
University of Western Australia|University of Western Australia|University of Oxford|University of Oxford
influential causal theory attributes dyslexia visual andor auditory perceptual deficits theory derives group differences individuals dyslexia controls range psychophysical tasks substantial variation individuals within group task task addressed two questions first psychophysical measures sufficient reliability assess perceptual deficits individuals second different psychophysical tasks measure common underlying construct studied 104 adults wide range reading ability two comparison groups 49 dyslexic adults 41 adults normal reading measuring performance four auditory two visual tasks observed moderate high testretest reliability tasks people dyslexia likely display poor task performance unable demonstrate either construct validity current theories perceptual deficits predictive validity reading ability suggest deficient perceptual task performance dyslexia may associated inconsistent marker underlying neurological abnormality rather causally implicated reading difficulties