Comparing derived and acquired acceleration profiles: 3-D optical electronic data analyses

Advances in technology in the last century have provided the opportunity to observe human behavior in one, two, and three dimensions with higher recording frequencies and greater spatial accuracy. Consequently, detailed analyses of individual trials and composite measures of multiple movement trajectories are possible. However, 3-D data have often been analyzed by performing independent analyses of the limb trajectory along each axis. Essentially, analyses of individual axes are often inappropriate as movement in each axis can contribute to the overall trajectory. Employing such methods can compound error throughout the analysis process. The purpose of this study was to determine appropriate post hoc and real-time 3-D optoelectronic data reduction procedures for manual aiming movements. Rapid goal-directed movements were recorded using an Optotrak and triaxial accelerometer. Data were separately subjected to second order Butterworth filters employing low-cut frequencies of 6-24 Hz in 2 Hz increments. Subsequently, acceleration profiles were derived by double differentiating the individual position profiles and then calculating the resultant acceleration profile. In addition, acceleration profiles were also calculated by finding the resultant position and the total distance traveled each frame prior to double differentiation. Root mean square error between the derived and acquired profiles was employed as our main dependent measure. Trajectories reduced with the total distance procedure produced the lowest root mean square error. The results are important for experimenters analyzing 3-D data post hoc and those implementing real-time manipulations.     

Inching towards wholeness: C.G. Jung and his relationship to Judaism

The evolution of Jung's relationship with Judaism is interpreted as reflecting aspects of the individuation journey over the course of a long life. The progress and limitations of his public positions and personal relationships are explored through his published work and correspondence. Perspectives from relational psychoanalysis and Jewish philosophy are used to amplify Jung's understanding of Jewish, and specifically Kabbalistic, text and image. Dimensions of the author's own journey toward greater acceptance of his own Jewish soul is also considered, along with the wider contemporary relevance of these themes.     

Externalizing Outcomes of Youth with and without ADHD: Time-Varying Prediction by Parental ADHD and Mediated Effects

Although parental attention-deficit/hyperactivity disorder (ADHD) is a risk factor for multiple negative youth outcomes, it is unknown how change in parental ADHD symptoms over time affects change in child ADHD symptoms; moreover, mediators of these predictions are largely unknown. Parents of 230 5–10 year-old children (68 % male) with (n = 120) and without ADHD (n = 110) were followed prospectively for 6–7 years across three separate waves. Parents self-reported their ADHD and depression symptoms and similarly rated offspring ADHD, oppositional defiant disorder (ODD), and conduct disorder (CD) symptoms; youth self-reported their substance use. Temporally-ordered mediators consisted of parental expressed emotion (EE), derived from the Five Minute Speech Sample, and self-reported positive and negative parenting behavior. Controlling for key demographics and parental depression symptoms, increasing parental ADHD symptoms were a time-varying predictor of worsening youth ADHD and ODD, although it was unrelated to change in CD and alcohol/substance use. Next, although EE facets (i.e., criticism, emotional over-involvement) did not mediate these predictions, negative parenting behavior significantly mediated predictions of youth ADHD (and marginally in predictions of ODD) from parental ADHD symptoms. These quasi-experimental findings suggest that parental ADHD symptoms are a potential unique causal risk factor for offspring ADHD and ODD; also, preventing negative parenting behavior secondary to parental ADHD symptoms is critical to improve trajectories of youth ADHD and ODD. We consider parental ADHD symptoms and family factors underlying emergent externalizing problems utilizing a developmental psychopathology framework, including implications for intervention and prevention.     

Stimulus-response incompatibility eliminates inhibitory cueing effects with saccadic but not manual responses

There are thought to be two forms of inhibition of return (IOR) depending on whether the oculomotor system is activated or suppressed. When saccades are allowed, output-based IOR is generated, whereas input-based IOR arises when saccades are prohibited. In a series of 4 experiments, we mixed or blocked compatible and incompatible trials with saccadic or manual responses to investigate whether cueing effects would follow the same pattern as those observed with more traditional peripheral onsets and central arrows. In all experiments, an uninformative cue was displayed, followed by a cue-back stimulus that was either red or green, indicating whether a compatible or incompatible response was required. The results showed that IOR was indeed observed for compatible responses in all tasks, whereas IOR was eliminated for incompatible trials—but only with saccadic responses. These findings indicate that the dissociation between input- and output-based forms of IOR depends on more than just oculomotor activation, providing further support for the existence of an inhibitory cueing effect that is distinct to the manual response modality.     

Exploring the Effects of Job Autonomy on Engagement and Creativity: The Moderating Role of Performance Pressure and Learning Goal Orientation

Purpose

The 21st century work environment calls for team members to be more engaged in their work and exhibit more creativity in completing their job tasks. The purpose of this study was to examine whether team performance pressure and individual goal orientation would moderate the relationships between individual autonomy in teams and individual engagement and creativity.

Design/Methodology/Approach

A sample consisting of 209 team members and 45 team managers from 45 work teams in 14 companies completed survey measures. To test our hypotheses, we used multilevel modeling with random intercepts and slopes because the individual-level data were nested within the team-level data.

Findings

Hierarchical linear modeling showed that team-level performance pressure attenuated the positive relations between job autonomy and three dimensions of engagement. There were also 3-way interactions between job autonomy, psychological performance pressure, and learning goal orientation in predicting three dimensions of engagement and creativity.

Implications

This study highlights the importance of exploring the moderating effect of team-level task characteristics and individual differences on the relationships between job autonomy and individual engagement and creativity. Organizations need to carefully consider both individual learning goals and performance pressure when empowering team members with job autonomy.

Originality/Value

This is one of the first studies to explore the association between individual job autonomy in teams and individual outcomes in a contingency model. We first introduced team performance pressure as a moderator of job autonomy and examined the 3-way interaction effects of performance pressure, individual job autonomy, and learning goal orientation.

     

Comparison of kinematic and kinetic methods for computing the vertical motion of the body center of mass during walking

The vertical excursion of the body center of mass (BCOM) was calculated using three different techniques commonly used by motion analysis laboratories. The sacral marker method involved estimating vertical BCOM motion by tracking the position of a reflective marker that was placed on the sacrum of subjects as they walked. The body segmental analysis technique determined the vertical motion of the BCOM from a weighted average of the vertical positions of the centers of mass of individual body segments for each frame of kinematic data acquired during the data trial. Anthropomorphic data from standard tables were used to determine the mass fractions and the locations of the centers of mass of each body segment. The third technique involved calculating BCOM vertical motion through double integration of force platform data. Data was acquired from 10 able-bodied, adult research subjects--5 males and 5 females--walking at speeds of 0.8, 1.2, 1.6, and 2.0 m/s. A repeated measures ANOVA indicated that at the slowest walking speed the vertical excursions calculated by all three techniques were similar, but at faster speeds the sacral marker significantly (p < 0.001) overestimated the vertical excursion of the BCOM compared with the other two methods. The body segmental analysis and force platform techniques were in agreement at all walking speeds. Discrepancies between the sacral marker method and the other two techniques were explained using a simple model; the reciprocal configuration of the legs during double support phase significantly raises the position of the BCOM within the trunk at longer step lengths, corresponding to faster walking speeds. The sacral marker method may provide a reasonable approximation of vertical BCOM motion at slow and freely selected speeds of able-bodied walking. However, the body segmental analysis or force platform techniques will probably yield better estimates at faster walking speeds or in persons with gait pathologies.     

Relations between vocabulary development and verbal short-term memory: The relative importance of short-term memory for serial order and item information

Although many studies have shown an association between verbal short-term memory (STM) and vocabulary development, the precise nature of this association is not yet clear. The current study reexamined this relation in 4- to 6-year-olds by designing verbal STM tasks that maximized memory for either item or serial order information. Although empirical data suggest that distinct STM processes determine item and serial order recall, these were generally confounded in previous developmental studies. We observed that item and order memory tasks were independently related to vocabulary development. Furthermore, vocabulary development was more strongly associated with STM for order information in 4- and 6-year-olds and with STM for item information in 5-year-olds. These data highlight the specificity of verbal STM for serial order and item information and suggest a causal association between order STM processes and vocabulary development, at least in 4- and 6-year-olds.