Evidence of Early Strategies in Learning to Walk

Learning to walk is a dynamic process requiring the fine coordination, assembly, and balancing of many body segments at once. For the young walker, coordinating all these behavioral levels may be quite daunting. In this study, we examine the whole‐body strategies to which infants resort to produce their first independent steps and progress over the first months of walking experience. Six infants were followed weekly from the onset of independent upright locomotion for 8 weeks, and then every other week until 4 months of walking experience. The walking kinematics from the infants' earliest steps were cluster‐analyzed and the infants were classified into 3 groups. Follow‐up comparisons with kinematics recordings were used to quantify the infants' strategies more precisely and track how these early forms of walking evolved over time. Results revealed that in the first weeks of independent walking, 3 infants used a stepping strategy, 1 used a twisting strategy, and 2 used a falling strategy to move their body forward and perform their first unsupported steps. As the infants gained walking experience, their walking patterns became more similar. These findings indicate that infants discover different solutions to use their body and control their balance when beginning to walk. With time, infants adopt a more efficient solution that incorporates and integrates elements of the different strategies.     

Esther Thelen

This study explored whether the reported inability of newborns to perceive object unity could result from the limited abilities of newborns to recognize the correspondence between 2 stimuli that were identical except for the presence or absence of an occluder. Five experiments were carried out using a visual habituation technique. The results of Experiment 1 indicated that newborns were capable of recognizing the perceptual correspondence between a nonoccluded and an occluded form. More intriguing, the outcomes of Experiments 2, 3, and 4 suggested that newborns find a partly occluded form to be more similar to a completely unoccluded form than to an unoccluded form containing a gap. Finally, even if newborns are able to perceive the correspondence between a partly occluded object and a complete form, the presence of this skill does not appear sufficient to imply the ability to manifest veridical object unity perception at birth (Experiment 5).     

Well-Being and Affective Commitment among Ambulance Volunteers: A Mediational Model of Job Burnout

ABSTRACT

Burnout represents a relevant risk for ambulance volunteers. According to the Job Demands-Resources model, role conflict and social support can be considered as antecedents of burnout which, in turn, may lower affective commitment. This study aims to investigate the relationship between social support, role conflict, and affective commitment, as mediated by job burnout. Survey data were collected from 352 Italian volunteers and analyzed using structural equation modeling methods. Social support was confirmed as a protective factor, and role conflict as an antecedent of burnout which, in turn, decreases affective commitment. The relationship between role conflict and affective commitment is mediated by burnout which, on the contrary, does not mediate the effect of social support on affective commitment. Social support may protect against burnout. Because of its positive effects on a personal and an organizational level, affective commitment may be increased raising levels of supervisor support and reshaping role expectations. It could be useful to carry out future longitudinal studies, in order to confirm the antecedents and effects of job burnout; furthermore, this research should be extended to other ambulance organizations, in order to generalize the results; finally, multi-group analyses would allow to bring out possible differences between paid-staff and volunteers.     

Assessment of Organizational Trust: Italian Adaptation and Factorial Validity of the Organizational Trust Inventory

Trust influences interactions among individuals and organizations but has been an elusive concept to define and measure. The Organizational Trust Inventory (OTI) measures three dimensions of organizational trust, as defined by Cummings and Bromiley (in: Kramer and Tyler (eds) Trust in Organizations, 1996), believing or feeling that others: keep commitments, negotiate honestly, and do not take excessive advantage. This research presents an original adaptation of the OTI for the Italian people. It can now be used to evaluate trust regarding colleagues, managers, suppliers, subordinates, clients, and organizations. Using a sample of 490 employees and structural equation modeling, we consider the validity of the questionnaire and the theoretical model articulation both across different counterpart and countries. Besides, we develop a new reduced-form of the questionnaire (OTI/R), which offers better psychometric properties than the long form.     

Infant Eye-tracking in the Context of Goal-Directed Actions

This paper presents two methods that we applied to our research to record infant gaze in the context of goal-oriented actions using different eye-tracking devices: head-mounted and remote eye-tracking. For each type of eye-tracking system, we discuss their advantages and disadvantages, we describe the particular experimental setups we used to study infant looking and reaching, explain how we were able to use and synchronize these systems with other sources of data collection (video recordings and motion capture) in order to analyze gaze and movements directed toward 3D objects within a common time frame. Finally, for each method, we briefly present some results from our studies to illustrate the different levels of analyses that may be carried out using these different types of eye-tracking devices. These examples aim to highlight some of the novel questions that may be addressed using eye-tracking in the context of goal-directed actions.