The existence of a phonemic deficit that is predictive of, and probably causal to, many cases of reading difficulty is well established. Tallal (1984) has suggested that this phonemic deficit is in fact a symptom of an underlying auditory temporal processing deficit. Our purpose in this paper is to evaluate the plausibility of this hypothesis. The various components that might constitute sequential (or temporal) processing are described. Our review of the literature reveals considerable evidence for a deficit in dyslexics in stimulus individuation tasks (e.g., gap detection) and temporal order judgments in both the auditory and visual modalities. The possibility that a general temporal processing deficit is associated with dyslexia, as suggested by Tallal (1984), is explored, and possible etiologies for such a deficit are discussed. The possibility of a causal link between temporal processing deficits and some reading disabilities is demonstrated, and converging evidence from morphological studies is reviewed. It is concluded that a temporal processing deficit does appear to be present in many developmental dyslexics, and strategies are suggested for further research aimed at evaluating the hypothesis that this deficit may be the root cause of a number of cases of dyslexia itself.

https://link.springer.com/content/pdf/10.3758/BF03210983.pdf

The evidence for a temporal processing deficit linked to dyslexia: A review.

Patterns of Paralexia: A Psycholinguistic Approach

(1985). The cognitive neuropsychology of developmental (and acquired) dyslexia: A critical survey. Cognitive Neuropsychology: Vol. 2, No. 2, pp. 169-205.

The cognitive neuropsychology of developmental (and acquired) dyslexia: A critical survey

Dyslexia, the apparently selective impairment in the ability to read words, or even individual letters, has been repeatedly described in association with left (major) hemisphere lesions. Verbal dyslexia, affecting the reading of words but not of isolated letters, may be characterized by paralexic errors (misreading of words). The paralexias may accompany similar (paraphasic) errors in spoken speech, and be secondary to a more general disorder of language function. They may occur in the 'parietal dyslexia' of Herrmann and Potzl (1926) described as involving 'the frequent intrusion of incorrect words or word fragments in place of the ones actually in the text'. Patients with 'spelling dyslexia' in the absence of aphasia (Wolpert, 1924), who can only read words letter by letter because of a pathological limitation of their ability to perceive forms simultaneously, which prejudices the simultaneous perception of the whole word (Kinsbourne and Warrington, 1962a), make paralexic errors if they try to maintain normal reading speed. In contrast, patients with right-sided (minor hemisphere) damage, though sometimes liable to lose their place on the printed line (Paterson and Zangwill, 1944), have not been reported to show verbal dyslexia. Below are described six right-handed patients with acquired right hemisphere lesions who suffered from reading disability. The paralexic errors were of a very characteristic, consistent, and hitherto undescribed type. They could be reproduced experimentally in a predictable fashion under the controlled conditions of tachistoscopic presentation of written material.

A variety of reading disability associated with right hemisphere lesions

In this study, 91 Finnish-speaking preschoolers (ranging in age from 6.4 to 7.4 years) were tested by using 2 structural equation models. None of the participants had entered school at the time of the study because the age of school entry in Finland is 7 years. The structural equation models were built particularly to examine the connections between children's reading abilities and their phonological skills. The main results of this study show that, in a very transparent language such as Finnish, the model that emphasized sensitivity to the phonological structure of the word as the prerequisite for learning to read fit our data well. The other model, which was likewise theoretically and statistically quite accessible, implied, by contrast, the reciprocity between learning to read and the emergence of phonemic awareness. The results of this study suggest that skills related to reading at preschool age are in many respects the same and have the same relations in a transparent language such as Finnish as the...

Two Alternative Ways to Model the Relation Between Reading Accuracy and Phonological Awareness at Preschool Age

Reading ability seems to involve analytic-sequential processing of selected letters and a holistic-simultaneous perception of the salient features of the entire word. The dyslexic child, being norm...

Dyslexia, an imbalance in cerebral information-processing strategies.

A perceptual exploration task involving three horizontal linear arrays of stimuli was administered to 167 children ranging in age from 3 to 7 yr. It was found that the well organized, predominantly right-to-left responses of very young children were eventually replaced by left-to-right patterns. A tachistoscopic test showed that Ss who gave right-to-left responses to the linear arrays showed hemispheric asymmetry of perception. The results were interpreted as supporting the view that directional response tendencies are related to hemispheric asymmetry.

Directional scanning and cerebral asymmetries in processing visual stimuli.

Specific reading disability or developmental dyslexia is a condition wherein an individual with average or superior intelligence does not acquire normal reading skills. This paper provides a tentative explanation of the paradoxical relationship between the reading disability and intelligence. Study of 15 dyslexic college students showed that they were deficient in grapheme-phoneme conversion and that the decoding skill could be an autonomous, specific ability that is independent of the "g" factor as expressed in terms of IQ. The decoding skill appears to be a subroutine and may, in dyslexia, operate as a limiting factor that affects reading comprehension.

P. G. Aaron

Papers

Dyslexia, an imbalance in cerebral information-processing strategies.

Directional scanning and cerebral asymmetries in processing visual stimuli.

The paradoxical relationship between intelligence and reading disability.