T. R. Miles

The incidence of Stroop interference in dyslexia

An experiment is reported in which dyslexics (on average ten-and-a-half years old) showed marked Stroop interference of a colour word on the naming of a colour. This interference was larger than that shown by control subjects matched for chronological age, but not larger than that experienced by a group of control subjects matched for reading age (about eight years old). Dyslexics show interference consistent with their reading age. It is hypothesized that the resources available to dyslexics for controlling automatic word reading are less than those for non-dyslexics of a similar chronological age.

Do Dyslexic Children Have IQs

Some of the problems which arise in trying to obtain IQ figures for dyslexic children are reviewed. It is suggested that the existence of these problems adds weight to the view that the concept of ‘global IQ’ is of dubious validity.

Extraneous bodily movements and irrelevant vocalizations by dyslexic and non-dyslexic boys during calculation tasks.

Thirty dyslexic boys, aged between 9 and 15 years, and 30 age-matched controls were tested on a series of sums involving division, subtraction and addition. During the testing a record was kept of any bodily movements or verbal utterances (vocalizations) irrelevant to the task in hand. It was found that the dyslexics produced many more extraneous bodily movements and many more irrelevant vocalizations than did the controls. Possible reasons for these findings are tentatively suggested.

The Performance of Dyslexic and Non-Dyslexic Boys at Division Sums

Publisher Summary There are evidences that dyslexics are slower than nondyslexics at operating with and remembering any kind of symbolic information but are unimpaired at ‘processing for meaning’ and recognizing regularities and patterns. Since division sums involve operating with and remembering symbols (numerals), it is observed that the dyslexics in the study would make more errors and be slower than the controls. Also it seemed possible that their weak memorization skills might be compensated for if there were obvious algorithms to help them, such as division by 10 and division by 11. The load on the memory is much less than it is for many of the other tables, since if one is dividing by 10 one simply has to remove the zero, while if one is dividing by 11 the correct answer is there in front of one. It seemed possible, therefore, that the presence of algorithms might lessen the differences between them and the controls. The aim of this chapter is to provide the answers of five important questions related to the performance of dyslexic and nondyslexic boys at division sums. These questions include: Did some division sums present more problems than others? Did the dyslexics make more errors than the controls? Were they slower in carrying out the calculations? Did the existence of an obvious algorithm affect the two groups differently? Does performance improve in a steady fashion with age or are there spurts and plateaux?