Neuropsychological assessment of learning disabilities: a discriminant analysis

The neuropsychological test scores of 23 learning disabled children were compared with those of a matched population of normal children in the 9-1 to 13-1 age range. All children were administered the Wechsler Intelligence Scale for Children-Revised (WISC-R), a dichotic listening task involving both free and directed recall conditions, a handedness inventory, the Tactile Performance Test and the Category Test from the Halstead-Reitan Neuropsychological Test Battery. A multivariate analysis of variance resulted in a significant separation between groups (p less than .001) using these procedures. A stepwise discriminant function analysis revealed that both of the directed dichotic tasks contributed the most of all 13 measures to the significant group separation. In addition, other cognitive tasks found to discriminate normal from learning disabled children include general verbal processes, concept formation, and tactile memory. These findings suggest that the directed dichotic listening procedure and the WISC-R Verbal IQ measure are reasonably valuable clinical tools in the classification of learning disabilities.     

The development of young children's awareness of logical inconsistencies

Research by Markman (1979) suggests that children up to 12 years of age do not spontaneously detect logical inconsistencies. The present study was directed to factors which may limit children's ability to recognize their failures to understand. A task was devised which involved materials that were clearly based on children's experiences, and which involved premises and conclusions which were presented contiguously, rather than being interspersed among other sentences. Ninety-six 5-, 6-, and 7-year-old children were asked to judge the acceptability of eight three-sentence “stories” told by a puppet, and were asked to justify their responses. The stories differed in whether they were consistent or inconsistent, and in whether the principle upon which a story's consistency depended was implicitly or explicitly stated. The results showed developmental differences. By Age 7 years, most children were quite capable of evaluating sentences for their logical consistency. Five-year-olds, however, did not perform as well on the task, especially when the information upon which the logical cohesiveness of the stories rested was implicitly, rather than explicitly, stated. An examination of the justifications provided by these children revealed that they tended to question the empirical validity of individual sentences, rather than integrate the story as a whole and examine its overall logical structure.     

Does reward depletion influence spatial memory performance?

If spatial memory tasks are considered as foraging problems, it can be predicted that rats' difficulty in learning a win-stay task—revisiting part of a maze where food has recently been found—should be partly overcome if the food is not fully consumed at the first visit (nondepleted reward) rather than being all eaten (depleted reward). Three experiments confirmed and further analysed this result. Experiments 1 and 2 showed that it does not depend on the amount of food initially found; nor is win-stay performance affected by the amount of food actually eaten. Experiment 3 suggested that the effects of nondepleted reward are mainly due to the animals' being interrupted while eating, and very little to the fact that uneaten food is left behind. The results are discussed with regard to their implications for learning theory, and for the application of foraging theory to learning and memory experiments.     

Perception of causal relations in humans: Factors affecting judgments of response-outcome contingencies under free-operant procedures

In three experiments, college studients responded to and rated a range of positive, random, and negative response-outcome contingencies presented in free-operant formats. These experiments sought a paradigm that would yield sensitive and unbiased judgments of response-outcome relations and explored the role of time in the judgment of response-outcome covariation. In Experiment 1, the effects of making continuous and discrete responses on subjects' contingency judgments were compared. In Experiment 2, the effects of changing the temporal definition of discrete responses were examined as were the effects of the amount of exposure to contingency problems. In Experiment 3, the effects of temporal regularity in defining response occurrence and nonoccurrence were investigated. In all three experiments, subjects' judgments were strong linear functions of the programmed contingencies between telegraph key operation and the illumination of a brief light. This result shows free-operant scheduling of response-outcome contingencies to be a highly sensitive and unbiased method of investigating causal perception. Additionally, judgment accuracy was found to be higher for males than for females and to improve as the probability of the subject's making a recorded response rose from .00 toward .50. Finally, a correlational analysis of several possible judgment rules supported the conclusion that subjects rated response-outcome relations on the basis of the difference in the probability of an outcome given their having recently made or not made a response.     

Pavlovian processes do mediate control of the “advance” response strategy

Two parallel experiments used pigeons in a transfer of control design to determine the basis of the transfer of the use of the “advance strategy” across successive discriminations (W. K. Honig & H. Lindsay, Learning and Motivation, 1975, 6, 157–178). Pigeons were first trained under instrumental contingencies to use an “advance” response to maximize their exposure to S^D and minimize their exposure to S^Δ. Then orthogonal stimuli (key lights in Experiment 1 and diffuse illuminations in Experiment 2) were independently established through separate discriminative Pavlovian procedures as CS+ and CS? or as CS^o's. Later in special tests, it was demonstrated that the associative values of the Pavlovian CS's were a major factor governing the use of the advance strategy: only pigeons exposed to $\text{CS+}\text{CS?}$ used the advance response to regulate their exposure to either CS. Although these experiments showed that the necessary and sufficient conditions for utilization of the advance strategy are the Pavlovian associative values of the discriminative stimuli, opportunity for differential “operant” responding during the discriminative stimuli seems to be a contributor to the optimal use of the advance response across successive discriminations.     

Written spelling deficit of Broca''s aphasics

The purpose of this study was to investigate the nature of the written spelling deficit manifested by Broca's aphasics. Four spelling tests were given to eight Broca's aphasic patients. Analysis of misspelling errors led the investigators to conclude that Broca's aphasics do not spell phonically, but rather adhere exclusively to a visual/orthographic strategy. Possible cognitive deficits underlying the spelling problem are identified. The written spelling deficit is related to other features of the syndrome of Broca's aphasia, and finally, speculations are offered concerning the neurological substrate of written spelling in Broca's aphasic patients.     

Inferential processing of context: Studies of cognitively impaired subjects

Language comprehension tasks involving pronoun coreference were administered to a group of demented patients, a group of patients with cardiac disease, and groups of normal elderly persons and young adults. Pronoun coreference was constrained by either lexical, syntactic, or contextual cues. No differences were found between old and young subjects for any task. While the demented patients were impaired on all tasks, the cardiac patients were specifically impaired in the inferential processing of context.     

The relationship of mathematics self-efficacy expectations to the selection of science-based college majors

The major purpose of the present study was to investigate the relationship of mathematics self-efficacy expectations to the selection of science-based majors in college males and females. Based on results obtained from a pilot sample of college students, an instrument assessing mathematics self-efficacy expectations was developed. The items used in the mathematics self-efficacy scale included everyday math tasks, math problems, and math-based college courses. Subjects, 153 female and 109 male undergraduates, completed the mathematics self-efficacy scale, the Bem Sex Role Inventory, an adapted version of the Fennema-Sherman Mathematics Attitudes Scales, and a questionnaire concerning their college major choices. Results indicated that mathematics self-efficacy expectations were significantly related to the extent to which students selected science-based college majors, thus supporting the postulated role of cognitive mediational factors in educational and career choice behavior. In addition, the math-related self-efficacy expectations of college males were significantly stronger than were those of college females. Implications of the findings for the process of educational and career decision-making are discussed.     

The problem of relapse in stuttering: Some thoughts on what might cause it and how to deal with it

Bloodstein recently wrote that “the most vital part of science is not accurate measurement or the insistence on empiricism. It is an attitude of inquiry into the how and why of things” [Bloodstein, O. Foreword. In: Maintenance of Fluency (E. Boberg ed.). New York: Elsevier, 1981, p. vii]. In the paper below, I present some unsubstantiated and no doubt controversial thoughts on the how and why of relapse in stuttering. The overall thrust of these thoughts is that stutterers have different propensities to stutter because of the inherent variability in their speech production systems. For this reason, for therapy to have long-range success, stutterers must learn to accept and deal with the inherent variability in their speech production mechanisms.