The chapter examines three related aspects of individual differences that are relevant to reading by touch: the development of language skills in conditions of visual handicap, retardation in braille reading, and effects of developmental and experiential factors on the process of learning.
Language skills are clearly important in the absence of sight, and, if anything, also more so for learning braille than print. Phonological competence is considered first. Some popular misconceptions and confusions about lexical knowledge and semantic concepts in congenital blindness are examined next.
The subject of specific reading difficulties is too large to be surveyed in detail here, and I shall not attempt it. It embraces problems shown by literate adults who have sustained specific brain damage, developmental dyslexia associated with phonological difficulties and deficiencies in learning to read, and the problems of children whose braille skills are retarded relative to the norms expected for their age and general level of ability for a variety of reasons. The term 'dyslexia' is often used interchangeably with the phrase 'specific reading difficulty'. But retarded reading does not have quite the same connotation in braille as in print. Older children who have learned braille late and lag behind their contemporaries, for instance, fall into the category of retarded readers who require educational help. But it would be inappropriate to consider them dyslexic. For clarity, distinctions between acquired dyslexias, from brain damage in adulthood, degrees of traumatic 'alexia' (linguistic problems) caused by specific brain damage at birth, and genetically (familial) caused or triggered developmental dyslexia are discussed briefly first. The term 'specific reading difficulty' is here used as a neutral umbrella term for children whose reading level is below that expected for their age and intelligence in the absence of known brain damage.
Findings on phonological, semantic and tactual coding of uncontracted familiar braille words by two independent sets of retarded and competent braille readers are discussed next. Two further sets of data on totally congenitally blind young retarded braille readers are presented. Similarities