Building theories of reading ability: On the relation between individual differences in cognitive skills and reading comprehension

To date most theories of reading ability have emphasized a single factor as the major source of individual differences in performance. However there has been little agreement on what that factor is. However, candidates have included visual discrimination, phonological and semantic recoding, short-term memory, and utilization of linguistic knowledge and context. The single- factor theories are summarized. Literature is then reviewed to show that no single-factor theory is likely to be right, because a very wide range of component skills and abilities has in fact been shown to correlate with reading success. Among them are discrimination of letter location and letter order during perceptual recognition, use of orthographic regularity as an aid to visual code formation, use of spelling-to-sound regularity in phonological recoding, memory for word order, spontaneous identification of syntactic relations, flexibility in prediction from syntactic and semantic context, and context-specificity in semantic encoding. It is concluded that more complex, multifactor models of reading ability are required, and some recent attempts to collect data conducive to such a model are described. In the process, three different approaches to identifying factors relevant to reading success are delineated. These are general abilities assessment, learning potential assessment, and component skills analysis. Two methods of conducting component skills analysis are presented, and it is recommended that they be used as converging operations. Finally, the results of a component skills analysis are used to construct a tentative example of a class of hierarchical models of reading ability that can be pursued developmentally.     

Development of the concepts of energy conservation and entropy

Development of the concepts of energy conservation and entropy was studied in children between 5 and 15 years of age. Energy conservation, as illustrated by the operation of double and colliding pendulums, was not well understood until about 15 years of age. Understanding of entropy was dependent on the particular apparatus used. When illustrated by the gradual mixing of rolling marbles of different colors, entropy was understood by 9- to 15-year-olds. But when illustrated by the eventual equalization of water levels in two interconnected containers, entropy was not well understood until about 15 years of age. Errors on a problem used to illustrate the conservation concept could often be characterized by the misapplication of the entropy concept and vice versa.     

Comprehension of gerundive constructions by Broca's aphasics

Eleven diagnosed Broca's aphasics were tested for comprehension of sentences containing gerundive constructions. Results showed that, as a group, these patients were sensitive to grammatical distinctions signaled by “function” words, contrary to the predictions of some current theories about the specific deficits exhibited in this syndrome. Further analysis showed that the patients fell into two subgroups, one which exhibited sensitivity to the distinctions in normal grammar, and another which exhibited no sensitivity to such distinctions. This suggests that the syndrome may have different manifestations in different populations—patient age is suggested as a possible means for distinguishing the two groups. Suggestions for further research into the nature of the comprehension deficits exhibited by Broca's aphasics are made.     

Fluency breaks in older speakers: Implications for a model of stuttering throughout the life cycle

In order to test a model describing the occurence of fluency breaks throughout the life cycle, spontaneous speech samples of 40 nonstutterers and 4 stutterers above the age of 50 were perceptually analyzed. Fluency breaks were classified into categories of formulative or motoric breaks. The results supported research, noting an increase in formulative fluency breaks (especially fillers and interjections) for older speakers. There was, however, a significant decrease in the occurence of formulative fluency breaks during the final years of late adulthood. No change was found in the occurence of motoric fluency breaks in the nonstuttering speakers. Stuttering speakers had significantly less formulative breaks and significantly more motoric breaks than nonstuttering speakers.     

Semantic field,naming, and auditory comprehension in aphasia

The status of semantic fields for 16 target nouns was compared in high and low comprehension aphasics, brain damaged, and normal controls, by measuring latency and miss rate for recognition of six classes of associates, which were presented orally on tape. The ability to name each target was also examined as a function of the integrity of the subject's semantic field for that word. Low comprehension aphasics showed both quantitative and qualitative changes in semantic fields, while milder aphasics showed only mild quantitative impairment, as compared to controls. Both latency and miss rate measures indicated that failure to name a word is associated with reduced semantic field for that word. This result is interpreted as supporting the view that nameing is, in part, determined by the convergence of associations.     

Effects of context-induced processing operations on semantic information acquired from discourse

Effects of context on processes involved in understanding discourse were investigated. An experimental context designed to directly affect discourse processing by inducing subjects to generate inferences involving text content was compared to a context in which subjects simply listened to and recalled the content of a text. The extent of inferential discourse processing was estimated from derived semantic information in subjects' text recalls. The experimental context produced effects on inferred and other derived information in subjects' text recalls which were predicted from a constructive model of discourse processing. Also consistent with this model, the amount of derived information increased with repeated exposures to the text. In a third condition, subjects repeatedly listened to the text in the experimental context, but only recalled it once on the last trial. The context produced very substantial effects on proportions of derived information under this condition. Context effects were still present one week later.