RITALIN VS. RESPONSE COST IN THE CONTROL OF HYPERACTIVE CHILDREN: A WITHIN-SUBJECT COMPARISON

A within-subject comparison was made of the effects of methylphenidate (Ritalin) and response cost in reducing the off-task behavior of two boys, 7 and 8 years of age, who had been diagnosed as having an attentional deficit disorder with hyperactivity. Several dosages of Ritalin (5 to 20 mg/day) were evaluated with the results indicating varying effects of the drug for both children. Response cost (with free-time as the reinforcer) was superior to Ritalin in raising levels of on-task behavior and in improving academic performance.     

Strategies in cross-modality matching

Subjects were tested on cross-and within-modality matching conditions with either a 5-sec or a 20-sec delay imposed between standard and comparison stimuli. Half the subjects were informed before the trial of what the comparison modality would be, while the others were not. There was a strong effect of instructions on the cross-modality conditions, but little on the within-modality conditions. The informed subjects showed better performance in the haptic-visual condition, while for the uninformed subjects, visual-haptic performance was better. The results suggest the importance of subjects’ processing strategies in cross-modality performance.     

Counting eliminates the repetition effect in judgments of temporal duration.

College student subjects estimated the duration of time intervals (8–54 sec) by counting or not (N=35 per group). Counting eliminated the repetition effect (a decline in the magnitude of estimations across trials), and resulted in a truncation of the psychophysical function. The former result was interpreted as contrary to Treisman's (1963) model. The latter result was attributed to the effortfulness of counting, which was established in a subsequent experiment.     

Operant conditioning of epileptic neurons in monkeys and its theoretical application to EEG operant conditioning in humans

This paper reviews a series of previous reports which summarize the physiology of chronic experimental epileptic foci in monkeys. It is shown that such monkeys can be trained to bidirectionally control the firing rates of normal and epileptic neurons which comprise the epileptic focus. As a result of this acquired operant performance, the monkeys show both a decrease in clinical seizures as well as a decrease in single unit epileptic activity. The EEC correlate of this change in single unit epileptic actvity is generalized EEG desynchronization. The conclusion from these data would indicate epileptic neurons can be operantly controlled and this control is not correlated with any specific EEG pattern. This brings to question the specificity of the SMR in EEG biofeedback paradigms which treat human epilepsy. This author feels that the result from such biofeedback studies are the result of the patient learning to manipulate electrical events within the CNS pathways through which the seizure propagates and is not contingent upon specific EEG frequencies.     

Perception of voicing and place features in whispered speech: A dichotic choice analysis

To offset shortcomings of existing demonstrations of right-ear superiority in the analysis of formant transitions, an experiment was performed on whispered speech. Two aspects of dichotic listening performance were examined in a single-report paradigm: the right-ear advantage (REA) for the perception of the voicing distinction and the feature sharing advantage (FSA) for both voicing and place features. A significant REA was obtained for the voicing distinction cued by first formant transition in the absence of a switch from aperiodic to periodic excitation. This, plus a greater incidence of voiced responses to right-ear stimuli, suggests that a distinction involving transitions can specifically augment the REA. The data also showed better identification of place and of voicing feature values when the competing dichotic speech stimuli shared these respective features (FSA) than when they did not. This FSA was restricted to the feature shared and hence not an effect of response uncertainty. The implications of these results for models of speech processing are discussed.     

Physical distance and attraction: An intensification effect

This study was designed to test the effects of both interaction distance and the quality of the interaction upon attraction. It was found that close interaction distances amplified the quality of the interaction so that for a positive interaction there was more liking for a close rather than a far partner, while for a negative interaction a close partner was liked less. The implications of this finding for research concerning crowding is discussed, as are possible explanatory mechanisms.     

The sex by race interaction in cognitive measures

Data consisting of 79 cognitive measures from Project TALENT for 100,000 white and black high school students have been analyzed for possible race by sex interactions. Control variables included geographical area, grade in high school, and socio-economic class. Race by sex interactions are largest when socioeconomic class is controlled and are highly related to the size of the main effect of sex as well. White boys and girls differ more than black boys and girls whether the overall sex difference favors males or females. Sex by grade and, to a lesser extent, sex by area interactions were also moderately large and consistent with the size of the main effect of sex. Since there are no consistent relationships with other main effects, and since the measures producing sex differences also tend to produce the interactions, it is concluded that sex differences and the interactions with sex share the same causes. Differences between these results and those of Jensen are also discussed.