A comparison of attentional and control shift models of the performance of concurrent tasks

A concurrent verbal task was superimposed upon the performance of a practiced bimanual motor skill by right-handed Ss. Addition of the verbal task did not increase the total number of errors; however, a significant interaction between hands and conditions was observed. The right hand made significantly more errors under the verbal condition, while the left hand made non-significantly fewer errors under that condition. These findings were interpreted as supporting an attentional model rather than a model which proposes that addition of the verbal task causes control of the right hand to shift to the non-verbal right hemisphere.     

The perceptual span and peripheral cues in reading

Skilled readers read passages that were displayed on a Cathode Ray Tube controlled by a computer. The readers' eye movements were monitored and certain critical words were changed by the computer as the eye was in motion. The experimental technique utilized in the study provided data on how wide the area is from which a reader acquires information during a fixation in silent reading. The results also delineate different types of visual information that are acquired from various areas within the perceptual span. It was found that a reader was able to make a semantic interpretation of a word that began 1–6 character spaces from his fixation point. When he fixated 7–12 character spaces prior to a word, he was able to pick up such gross visual characteristics as word shape and initial and final letters. It was concluded that the skilled reader is able to take advantage of information in the periphery. However, the size of the area from which he does is rather small.     

The internal representation of numbers

A principle of second-order isomorphism asserts that the functional similarities among internal representations parallel the structural similarities among the external objects to which those representations correspond. In accordance with this principle, subjects were asked to rate the similarities of all pairs of the numbers 0 through 9 in each of 24 conditions distinguished by the forms into which they were to be mentally transformed and then judged-including the visual forms of rows of dots and Arabic numerals, the auditory form of spoken English names, and the amodal form of the abstract concepts of the integers themselves. Similarity ratings were found to depend entirely upon the form in which the numbers were to be judged and not at all upon the form in which they were actually presented. Regardless of the form presented, multidimensional scaling solutions for each of the 24 conditions were readily interpretable in terms of structural properties of the form judged-curvature and closure for visual numerals; number of syllables, initial consonant, and vowel phoneme for auditory names; and numerical magnitude, odd-evenness, etc., for abstract concepts. Reanalyses of chronometric data are presented to illustrate how a fuller understanding of human cognitive processes may be attainable by using such structural models of internal representation in conjunction with studies of overt confusion and reaction time.     

Cognitive reference points

Two methods were used to test the hypothesis that natural categories (such as colors, line orientations, and numbers) have reference point stimuli (such as focal colors, vertical and horizontal lines, and numbers that are multiples of 10) in relation to which other stimuli of the category are judged. In Experiment I, subjects placed pairs of stimuli into sentence frames consisting of linguistic “hedges” such as “— is essentially—.” Results were that the supposed reference stimuli were most often placed in the second (reference) slot. In Experiment II, the subject placed a stimulus in physical space to represent his feeling of the psychological distance of that stimulus from another spatially fixed stimulus. Results showed that, when supposed reference stimuli were fixed, other stimuli were placed closer to them than vice versa. The results have substantive implications for the understanding of internal structure of categories and methodological implications for the mapping of reference points, quantification of linguistic intuitions, and the assumption of symmetry in psychological distance judgments.     

TEACHING GENERATIVE USE OF SENTENCE ANSWERS TO THREE FORMS OF QUESTIONS1

Three retarded and four economically disadvantaged children were taught, through modelling and reinforcement procedures, to produce complete sentences in response to three types of questions involving changes in verb inflections. To evaluate generalization of training, new but similar questions were periodically asked, answers to which were never modelled or reinforced. Modelling and reinforcement effectively taught correct sentence answers to training questions and produced new sentence answers to questions for which no specific training had been given.     

A clinical trial of continuous, intermittent and overlearning ‘bell and pad’ treatments for nocturnal enuresis

Sixty-one enuretic children were allocated sequentially to ‘standard’, ‘intermittent’ or ‘overlearning’ bell and pad treatment. The results suggest that the ‘overlearning’ modification of standard treatment was successful in bringing about a reduction in the relapse rate. The present status and implications of research into nocturnal enuresis were discussed in the light of the results of the investigation.