Perceptual-Motor Contributions to Static and Dynamic Balance Control in Children

The authors addressed balance control in children from the perspective of skill development and examined the relationship between specific perceptual and motor skills and static and dynamic balance performance. Fifty 11- to 13-year-old children performed a series of 1-legged balance tasks while standing on a force platform. Postural control was reflected in the maximum displacement of the center of mass in anterior-posterior and mediolateral directions. Simple visual, discrimination, and choice reaction times; sustained attention; visuomotor coordination; kinesthesis; and depth perception were also assessed in a series of perceptual and motor tests. The correlation analysis revealed that balancing under static conditions was strongly associated with the ability to perceive and process visual information, which is important for feedback-based control of balance. On the other hand, when greater task demands were imposed on the system under dynamic balancing conditions, the ability to respond to the destabilizing hip abductions-adductions in order to maintain equilibrium was associated with motor response speed, suggesting the use of a descending, feedforward control strategy. Therefore, like adults, 11- to 13-year-old children have the ability to select varying balance strategies (feedback, feedforward, or both), depending on the constraints of a particular task.     

Reacquisition and Transfer of Motor Skills With Sensory Feedback Reduction

Reacquisition and transfer of Morse key tapping and finger circling under total peripheral feedback reduction were investigated. 23 medical students were tested. Kinesthetic and tactile feedback were reduced by compression block. The results showed that tapping performance was reacquired to 56.4% of normal and circling to 26.4% by the tenth preshift trials. Strong positive transfer was found for both tasks in Groups 1 and 2. This positive transfer indicated the existence of central, general programming operations. With trials alternating between the two tasks (Group 3) reacquisition curves followed the preshift trials for tapping and circling, showing absence of adverse emotional influence of the block technique. Marked individual differences in performance in the absence of peripheral information were observed, grouping Ss into two distinct categories.     

Transfer Variables in Tracking Skills

In the present work the effect of two task variables on transfer were studied: shape of the track-circular or triangular; and target speed-constant or variable. One or both of these variables was changed on transfer. Experimental conditions were (a) 10 preshift and 10 post-shift trials, and (b) 20 single-trial alternations of two tasks. 22 groups of 12 Ss each were tested. Condition (a) showed positive transfer with single variable change and zero or negative transfer with simultaneous change in two variables, and condition (b) annulled all transfer effects. Results are discussed in terms of commonality between tasks and receptor and perceptual anticipation.     

Handedness and Hemispheric Asymmetry in the Control Of Movements

This study investigated the influence of hemispheric specialization of function on the motor performance of the hands. Right-handed (n=17), ambidextral (n=21), and ambisinistral (n=12) subjects performed Fitts' (1954) reciprocal tapping task under two conditions with each hand. Conditions had the same index of difficulty but differed in movement precision. The left hand of righthanders was superior in the condition requiring the greatest amount of preprogramming. Conversely, the right hand was not superior in the condition having the greatest demand for feedback control. For ambidextrals, left-hand superiority in the relatively preprogrammed condition was also revealed. Ambisinistrals showed no significant difference between conditions with either hand. The results partially support the hypothesis that the motor performance of the hands mirrors the dominant processing mode of their contralateral hemisphere. Failure to find supportive evidence in ambisinistrals is consistent with the contention that they lack hemispheric specialization of function.     

Acquisition of Predictable Vertical Visual Targets: Eye-Head Coordination and the Triggering Effect

The study was designed to investigate target acquisition in the vertical plane with emphasis on establishing strategy differences associated with acquisition triggering methods. Eight subjects were tested. Measurements consisted of target acquisition time, eye-head latency differences, velocity of gaze, eyes and head, and head amplitude. Using 3-way repeated measures analyses of variance the results show that the strategy for acquisition of predictable visual targets in vertical plane with the head unrestrained significantly depended on (a) the direction of the gaze motion with respect to the gravity vector (i.e., there is significant up-down asymmetry), (b) the angular distance of the target, and (c) the method of triggering the command to acquire the target—external versus internal. The data also show that when vertical acquisition is compared with triggering methods in the horizontal plane there is a difference in overall strategy for the acquisition of targets with the same spatial distances from straight ahead gaze when both the eyes and head are used. Among the factors contributing to the difference in strategy for vertical target acquisition are the gravitational vector, the relationship of target displacement and vestibular activitation, biomechanical and neural control asymmetries, and the difference in the vertical field of view.     

Hostility on the TAT as a Function of Defensive Inhibition and Stimulus Situation

It was hypothesized that there would be significant differences in the aggressive imagery of inhibited and uninhibited subjects when TAT cards or instructions strongly suggested an aggressive response but not when the experimental conditions did not suggest hostile themes. This prediction was verified on a sample of women but no support was found in a sample of men. The findings were related to other studies in the literature and directions for further research suggested.     

Motivation for Parenthood

Summary: The relationships between the tendency of subjects to perceive temporal zones as interrelated or discrete and other temporal behaviors and personality factors were explored in two studies, one using 115 college students and the other 60 college students, employing the Personal Orientation Inventory the Temporal Orientation Inventory, and the Circles Test. Subjects who obtained higher time-relatedness scores were found to demonstrate greater self-actualization, evaluate the present time mode more positively, overestimate time intervals in an estimation task, and to perform less accurately in time estimation than low time relaters.     

Religion and Disparities: Considering the Influences of Islam on the Health of American Muslims

Both theory and data suggest that religions shape the way individuals interpret and seek help for their illnesses. Yet, health disparities research has rarely examined the influence of a shared religion on the health of individuals from distinct minority communities. In this paper, we focus on Islam and American Muslims to outline the ways in which a shared religion may impact the health of a racially, ethnically, and socioeconomically diverse minority community. We use Kleinman’s “cultural construction of clinical reality” as a theoretical framework to interpret the extant literature on American Muslim health. We then propose a research agenda that would extend current disparities research to include measures of religiosity, particularly among populations that share a minority religious affiliation. The research we propose would provide a fuller understanding of the relationships between religion and health among Muslim Americans and other minority communities and would thereby undergird efforts to reduce unwarranted health disparities.     

March of the Living, a Holocaust Educational Tour: Effect on Adolescent Jewish Identity

March of the Living (MOTL) is a worldwide two-week trip for high school seniors to learn about the Holocaust by traveling to sites of concentration/death camps and Jewish historical sites in Poland and Israel. The mission statement of MOTL International states that participants will be able to “bolster their Jewish identity by acquainting them with the rich Jewish heritage in pre-war Eastern Europe.” However, this claim has never been studied quantitatively. Therefore, 152 adolescents who participated in MOTL voluntarily completed an initial background questionnaire, a Jewish Identity Survey and a Global Domains Survey pre-MOTL, end-Poland and end-Israel. Results suggest that Jewish identity did not substantially increase overall or from one time period to the next.