Swazi children's understanding of time concepts: a Piagetian study

The development of conservation skills in tasks dealing with temporal and nontemporal concepts was investigated. Contrary to findings of previous researchers, time conservation tasks presented few difficulties for children from a non-technological culture. Consistent with the results of previous research, however, time conservation tasks did appear to be more difficult than related tasks employing similar materials.     

Development of time concepts: differentiating clock and calendar from apparent durations

To investigate the role of perception and stress on time concepts, the real-time and apparent durations of common events varying in length from 30 s to 4 years were rated by kindergarten through 12th-grade pupils, college students, professors, and stress-impaired adults (N = 1,788). The events were pleasant, neutral or unpleasant; either directly perceptible and of specific duration or perceptually vague; and happened either to oneself or to someone else. Second graders differentiated apparent from real-time durations and, therefore, already had an abstract concept of time. As predicted from differentiation theory (Gibson, E. J., 1969; Gibson, J. J., 1966, 1983), longer durations were acquired later than shorter ones; perceptually-vague durations were acquired later than clearly perceptible ones of similar length; and, as Neisser (1976) also suggested, stress did not lead to regression, nor did the personal-impersonal dimension make a difference during childhood.     

Cognitive operations associated with individual differences in affect intensity

There are wide individual differences in the characteristic intensity of affective response to the same emotion-evoking event. The processes whereby individuals come to experience strong or mild emotional responses when exposed to the same affect-provoking stimuli are still unclear. In these studies, we propose that individual differences in affect intensity are associated with certain cognitive operations used during exposure to emotion-relevant stimuli. Specifically, cognitive operations that involve personalizing, generalizing, and selective abstraction were hypothesized to discriminate subjects high and low in affect intensity. Two studies replicated support for the hypothesis that subjects high on the affect-intensity dimension engage in more personalizing/empathic and more generalizing/elaborative cognitive operations than do subjects low on the affect-intensity dimension. The same cognitive operations discriminated groups high and low in affect intensity in response to both positive and negative emotional stimuli. Also, the cognitions that discriminated subjects high and low in affect intensity occurred only in response to affective stimuli; neutral stimuli did not evoke divergent cognitive operations for these two groups. Finally, a high degree of consistency was found in the use of emotion-relevant cognitive operations across positive and negative affective stimuli.     

Fusing Apples and Oranges: A Rejoinder to Carver & Scheier and to Fenigstein

ABSTRACT A simple parable is introduced that serves as an analogy to the private/public self-focus distinction The analogy elucidates that the reliability of the effects observed by the private/public research direction is not the focus of the Wicklund and Gollwitzer critique Rather, the critique questions the validity of the explanations offered More importantly, the analogy implies the conclusion that construing social dependency as an issue of self-focus does injustice to both the social dependency and self-focus concepts     

Task-dependent compensatory responses to perturbations applied during rhythmic movements in humans

Modulation of the responses to perturbation applied during different phases of three rhythmic movements in humans-running, cycling, and hopping-was studied. The perturbation was an electrical stimulus. The results showed gating and modulation of the responses in both ipsi- and contralateral limb muscles. The responses during running and cycling were only excitatory in nature, while during hopping an inhibitory response was observed. These responses were not correlated with the normal activity during the movement. The latency of the response in general was not altered for different stimulation phases. The alterations in the step cycle demonstrated overt behavioral changes due to the responses. There were differences between the responses observed during these movements and walking. In running, the major adaptation to perturbations appears to be in the contralateral side as seen in the changes in the step cycle. During cycling (except for one phase) and hopping, the same set of muscles was activated in response to perturbation. This represents a simplifying strategy in response organization. The dependency of the response on the task characteristics, postural stability requirement, and external constraints imposed on the subject is discussed. These studies provide insights into task-dependent strategies adopted by the nervous system to meet unexpected perturbation during rhythmic movements in humans.     

Lateral asymmetry in visual detection under hypnosis

It has been suggested that the hypnotic state results in a greater relative activation or priming of the right cerebral hemisphere than of the left hemisphere. The experiment reported here employed hypnosis to produce such a priming effect in a visual-detection task. Subjects were required to detect the presence or absence of a gap in outline squares presented either to the left visual field or right visual field, with response time as the primary dependent measure. Those subjects who were hypnotized produced a 50-msec. response time difference favoring squares presented to the left visual field whereas control subjects and simulator-control subjects showed no lateral asymmetries. The result is classified as a material-nonspecific priming effect and discussed with regard to the nature of processing resources.     

References for motor tasks--gender differences across age in motor performance: a meta-analysis

In 1985 we published a meta-analysis of gender differences across age in motor performance in Psychological Bulletin, but it did not include an indexing of each motor task to the references from which it was obtained. This paper provides a table listing the 20 motor tasks and the references from which data for each task were taken. The range of tasks was from fundamental movements (e.g., catching, jumping, running, throwing) to motor fitness (e.g., agility, arm hang, balance, grip strength) to perceptual-motor abilities (e.g., anticipation timing, fine eye-motor coordination, pursuit-rotor tracking, reaction time). The arm hang was represented in the fewest papers (n = 2) while the dash and long jump were most frequently referenced (n = 21).     

Interhemispheric integration of compound nouns: effects of stimulus arrangement and mode of presentation

Normal subjects had to name German compound nouns which were presented tachistoscopically. The compound nouns were displayed either unilaterally to the left or right visual field or bilaterally with one element to each visual field. In the bilateral condition a distinction was made as to whether familiar or unfamiliar arrangement of the elements was used. Representation in print was compared with pictorial representation of the compound nouns. A right visual-field superiority was observed with printed representation, but no laterality effects with pictorial representation. Bilateral processing was superior to unilateral processing. Within the bilateral conditions, the familiar arrangement of the elements yielded a significantly better performance than unfamiliar arrangement. This difference can be explained by reading habits and/or by different styles of interhemispheric integration.     

Handedness and dementia

Some researchers have speculated that left-hand dominance is more prevalent among patients suffering from dementia of the Alzheimer's type which began prior to age 65 yr. and that, in those patients, the disease runs a more rapid course. In the present study, seven left-handed dementia patients were matched with seven right-handed dementia patients on the basis of age and years of education and were compared with regard to neuropsychological compromise. While the left-handed group was somewhat more impaired than the right-handed subjects, the difference between the two groups was not statistically significant.