Handedness and stuttering: A dead horse?

A handedness questionnaire was administered to 446 stutterers and a control group. No significant male/female or stutterer/control effects were found, although both males and stutterers tended to be less right handed. The slight sex effect in handedness is consistent with previously reported studies and with cerebral structural and functional asymmetries.     

Brain perfusion and neuropsychological test scores: A correlation study in aphasics

In 26 patients suffering from the pure types of aphasias (11 total, 6 motoric, 5 sensory, and 5 amnesic), hemispheric and regional cerebral blood flow were measured and the flow values were correlated with psychological test scores including Wechsler Adult Intelligence Scale (WAIS), Token Test, Benton Test, and word fluency tests. With respect to the flow values, an overall difference between the groups of aphasics was proved by analysis of variance [regional cerebral blood flow (rCBF): F(3,22) = 13.77, p < .001]. The location of mainly impaired brain perfusion was not always confined to the centers within the speech area expected in view of the clinical disturbance, but most patients had neurologic deficits in addition to their aphasia. High correlations were found between the rCBF values within ischemic foci and WAIS subtests, as well as Token Test and word fluency tests. The correlation coefficients calculated between hemispheric flow and the psychological data indicated, in many instances, the same dependency, but did not attain the high statistical significance obtained with the regional values. The results show dependencies of several aspects of mental function upon cerebral perfusion and provide information for possible mechanisms responsible for the disturbance of nonverbal intelligence in aphasics.     

Text comprehension in aphasia

The semantic and pragmatic strategies in the comprehension of spoken texts are investigated in four subgroups of aphasic patients and in normal and brain-damaged controls. Short texts of similar linguistic structure were read to the subjects, who were required to choose the picture, from a multiple choice set of five, that was appropriate to the story. Besides a picture showing the main event of the story, one picture depicted the literal sense of a metaphorical comment, and the others misrepresented semantic functions expressed in the text. With respect to these types of responses, both aphasics and controls exhibited the same pattern of reaction. It is concluded that the redundancy of texts makes up for the difficulties aphasics have in comprehending isolated words and sentences.     

Epilepsy by looking at patterns]

The author, after pointing out the rare occurence and peculiarities of pattern-sensitive forms of epilepsy, reports the case of a seven-year-old boy with infantile cerebral paresis characterized by symptomatic attacks, who was observed to show absence-like conditions when looking at small-checkered patterns of nylon fabric. Grasping and looking at such fabrics assumed the form of an addiction, with a sense of pleasure being believed to be derived therefrom. Although anticonvulsive therapy resulted in attacks of epilepsy being no longer detectable clinically and by electroencephalography, seizures were still triggered by looking at patterns. Also discussed in this article is the problem of transition from real to psychogenic attacks.     

Conceptual encoding and locus of the Stroop effect

Subjects reacted to coloured season and month names by naming the season associated with the print colour of the word, or by naming the season opposite to the one associated with the print colour. Reactions were facilitated in both tasks when the word on the display named the season associated with the colour or was a month belonging to that season. Opposite season naming was not facilitated when the word named the response which the subject made. A comparable effect of print colour was found when subjects reacted to season names by naming the colour associated with the name, or with its opposite. These results suggest that Stroop congruity and interference effects occur during conceptual encoding, and not during response production.     

A simple technique for correlating film and EMG in locomotion studies

Two recurring problems hampering investigations of muscular activity patterns during locomotion are electrical “noise” and movement artifact in the electromyographic (EMG) signal and proper synchronization of behavioral events to the EMG. A relatively simple technique for achieving these ends is presented. Vigorous locomotor movements of unrestrained animals are recorded on 16-mm film and synchronized with one or more EMGs from selected muscles with little electrical noise or movement artifact interference. The system employs telemetry which is compared to hardwire techniques.     

Time errors are perceptual

Summary Methods for the measurement of time-errors (TEs) in the comparison of successive stimulus magnitudes are discussed. Combining a Thurstonian scaling method with the assumption of a fixed subjective width of the equal category, independent of stimulus level, a ratio scale for subjective differences within pairs of successive stimuli is derived. In a tone duration comparison experiment, with the TE defined in the terms of these subjective duration differences, data from four experimental groups were compared, the groups using different modes of judging and responding. Only minor effects of this factor were found, and hence it is concluded that the TE is a true perceptual phenomenon rather than an effect of response bias, criterion bias, or mediating verbal responses to the absolute level of stimulation. The quantitative results are interpreted in terms of a general model for the comparison of successive stimuli, employing the concepts of adaptation and differential weighting of sensation magnitudes.This investigation was supported by grants to the author from the University of Stockholm and from the Swedish Office of Administrative Rationalization and Economy (for computer time), and by grants to Mats Björkman and Hannes Eisler from the Swedish Council for Social Science Research, whose free consultation service at the Department of Statistics, University of Stockholm, also benefited the author.