Eye Movements Affect Postural Control in Young and Older Females

Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions

Predictors of social competence in middle childhood: Discriminating between peer status groups

The purpose of the study was to determine the relative importance of multiple variables in predicting social competence in middle childhood, as defined by peer status groups. In addition, the study sought to determine how effective the combination of variables were in predicting peer status group membership. Peer status is considered an operational measure of social competence and was used as the criterion variable. The peer status groups generated via sociometric nomination measures were popular, rejected, neglected, and average. The predictor variables in this study were academic achievement, social goals, self-perception, sibling warmth, and parenting style. Participants were 216 third- and fourth-grade students. All participants completed the nomination based sociometric measures and self-report measures assessing four predictor variables. Academic achievement data were independently collected by the researcher via student report cards. Separate logistic regressions were conducted for each status group and the set of predictor variables. A discriminant function analysis was conducted with all status groups and the set of predictor variables. Results indicated that academic achievement was consistently the best predictor of peer status, with self-perception and authoritarian parenting (only for participants with siblings), also providing significant levels of predictive utility. These variables were found to best differentiate children rejected by their peers from the rest of the sample