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.     

Effects of false increasing,decreasing, and true electromyographic biofeedback on the frequency of stuttering

Adult stutterers received auditory feedback of laryngeal area muscle activity while reading aloud under three conditions: (1) False Increasing Feedback, (2) False Decreasing Feedback, and (3) True Feedback. The subjects were unaware that the feedback in two conditions was being altered and were instructed not to manipulate the feedback signal. Decreases in the frequency of stuttering were observed for both the false increase and true feedback conditions. Factors contributing to the effectiveness of biofeedback techniques with stutterers are discussed.     

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.     

Stage 2 processing and the divided-attention effect

In two experiments subjects performed a choice-reaction-time (CRT) task and a second task concurrently. The second task was a simple reaction-time task in Experiment 1 and sentence generation and recall tasks in Experiment 2. Both studies yielded two main findings: Performance of the second task was not affected by CRT memory load (one, two, or four items), and the requirement to perform the second task did not affect the rate of increase of CRT with memory load. The first finding indicates that the effect of memory load on CRT is attributable to memory scanning, or Stage 2 processing, and is not an artifact of the rehearsal demands of the CRT memory set. The second finding indicates that Stage 2 processing is not sensitive to division of attention between the CRT and a second task.     

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.     

Modification of impulsive tempo in learning-disabled pupils

Thirty-three impulsive learning- disabled males, aged 9–12 years, were assigned to one of three treatment conditions: (a) Modeling, in which subjects were exposed to a videotape of a boy demonstrating reflective problem-solving activities and instructing himself to perform cautiously; (b) Modeling Plus Self-Verbalization, in which subjects observed the same videotape and were additionally required to verbalize similar reflective instructions; and (c) Control, in which subjects were shown a videotape of the task materials used in the modeling videotape, but without the model. Subjects were tested immediately after exposure to treatment, and again 3 weeks later, on different forms of the Matching Familiar Figures test. Both Modeling and Modeling Plus Self-Verbalization conditions were superior to Control in reducing errors on the immediate test, but the three treatments did not differ on the delayed test. No significant differences among the three conditions were found with regard to response latency. Discrepancies between the present results and those of previous related studies were noted, and potential research directions were suggested.The authors appreciate the cooperation and support of Mr. Dan Hurd, superintendent of DeKalb County Special Education Association.     

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.