Comparison of contingent and noncontingent access to therapy dogs during academic tasks in children with autism spectrum disorder

This study compared contingent and noncontingent access to therapy dogs during educational tasks for children with autism spectrum disorder using a multielement design. The experimenters assessed whether initial preference for the dog predicted reinforcer efficacy and how preference changed across time. A higher response rate during contingent dog sessions than baseline sessions occurred for 4 out of 5 participants, suggesting that the dog functioned as a reinforcer. One participant engaged in a high rate of responding in both contingent and noncontingent dog conditions. Preference assessments revealed idiosyncrasies, suggesting that further research is needed into the predictive nature of initial preference assessments with animals as part of the stimulus array. The experimenters also analyzed salivary cortisol before and after sessions to determine if learning about the upcoming interaction with a dog reduced salivary cortisol in children. Cortisol was variable across participants, with only some deriving a potential physiological benefit from expecting to interact with the dog.     

Posture based motor planning in a sequential grasping task

Movement planning in sequential tasks is revealed by grasping postures. We explored aspects of planning a sequential drawer opening and object manipulation task with regard to arm and torso postures. We conducted a detailed kinematic analysis of joint postures at the wrist, elbow, and shoulder for a one-grasp and a two-grasp sequence of movement. The second of the two-grasp sequence was constrained (uncomfortable). We predicted that planning for the second grasp in a two-grasp sequence would influence arm, torso, and whole-body postures at the first grasp. Participants prepared for the second grasp by adjusting the posture of the elbow and shoulder and the distance they stepped to the drawer. The joint postures at the elbow and shoulder changed in the direction of the intended object grasp. These findings show that anticipatory adjustments are revealed at postures other than the end-effector and lend insight into the mechanisms of sequential movement planning.     

Synchronization in repetitive smooth movement requires perceptible events

Accurate timing performance during auditory–motor synchronization has been well documented for finger tapping tasks. It is believed that information pertaining to an event in movement production aids in detecting and correcting for errors between movement cycle completion and the metronome tone. Tasks with minimal event-related information exhibit more variable synchronization and less rapid error correction. Recent work from our laboratory has indicated that a task purportedly lacking an event structure (circle drawing) did not exhibit accurate synchronization or error correction (Studenka & Zelaznik, in press). In the present paper we report on two experiments examining synchronization in tapping and circle drawing tasks. In Experiment 1, error correction processes of an event-timed tapping timing task and an emergently timed circle drawing timing task were examined. Rapid and complete error correction was seen for the tapping, but not for the circle drawing task. In Experiment 2, a perceptual event was added to delineate a cycle in circle drawing, and the perceptual event of table contact was removed from the tapping task. The inclusion of an event produced a marked improvement in synchronization error correction for circle drawing, and the removal of tactile feedback (taking away an event) slightly reduced the error correction response of tapping. Furthermore, the task kinematics of circle drawing remained smooth providing evidence that event structure can be kinematic or perceptual in nature. Thus, synchronization and error correction, characteristic of event timing (Ivry, Spencer, Zelaznik, & Diedrichsen, 2002; Repp, 2005), depends upon the presence of a distinguishable source of sensory information at the timing goal.     

Extending end-state comfort effect: do we consider the beginning state comfort of another?

Sharing a drink or passing a tool to another person is frequently done in our daily lives. However, a second thought is rarely given about how the object should be handed; instead we pay attention to other factors (e.g., the company). This interaction (handing a tool to someone) is interesting, since it may give insight to how motor intentions are predicted. Research has demonstrated that individuals exhibit an end-state comfort effect when manipulating objects, and it is of interest to determine how this is applied to a joint-action paradigm. The purpose of this experiment was to determine if participants would anticipate the confederate's postural requirements and pass tools in a manner that allowed the confederate to have beginning state comfort and thus facilitate the motion sequence as a whole. That is, would the participant incur the cost of the movement by adopting an awkward posture to facilitate the use of the tool by the confederate? The results demonstrated that participants allowed the confederate to adopt a comfortable beginning state comfort on 100% of the trials for all the tools. However, the participants did not sacrifice end-state comfort, demonstrating that the participants were able to plan ahead to both maximize their own end-state comfort and the beginning state comfort of the confederate.     

Daily Occupations,Routines, and Social Participation of Homeless Young People

Homelessness disrupts young people’s participation in the productive occupations that facilitate transition to adulthood, impairs social connections, and has a disorganizing effect on their time use. Semi-structured focus group interviews were used to explore how 19 homeless young people perceived their daily routines, meaningful occupations, and social participation to be impacted by the experience of homelessness. Occupational therapy practitioners can use the findings from this study to inform the development of comprehensive community-based programming aimed at increasing social opportunities, developing balanced, healthy routines, decreasing intrinsic and extrinsic barriers to residential stability, and promoting participation in productive and leisure occupations.     

Quality of Life in Gulf War Veterans: the Influence of Recency and Persistence of Psychiatric Morbidity

Important contributors to quality of life (QOL), such as psychosocial factors, have received limited exploration in veteran populations, in contrast to a significant amount of research focused on health-related quality of life (HRQL). This study investigated QOL and HRQL amongst Gulf War veterans compared with an era-military comparison group 20 years after the 1990/91 Gulf War, and whether psychiatric status over time and psychiatric comorbidities predicted QOL and HRQL. We then investigated which of a range of psychological health, physical health and social factors contribute greatest to QOL. Psychological interviews and postal questionnaires were administered to a cohort of Gulf War veterans and a military-era comparison group in 2000–02 and 2011–12. Gulf War veterans had poorer QOL and HRQL compared with a military comparison group, but the pattern of factors that influenced QOL was the same for both groups. Poorer QOL and HRQL were significantly associated with more recent and persistent psychiatric morbidity over time. Further analyses showed that affective disorders, followed by anxiety disorders had the largest impact on QOL and HRQL, and that QOL and HRQL were negatively affected by each additional psychiatric diagnosis. The importance of these findings was highlighted in a structural equation model that revealed psychological health contributed most to QOL, social support contributed a moderate amount, but physical health contributed only a very small amount. QOL in veterans is an important issue even many years after deployment and psychological health plays a predominant role in QOL.

     

Crossing the arms confuses the clocks: Sensory feedback and the bimanual advantage

The bimanual advantage refers to the finding that tapping with two fingers on opposite hands exhibits reduced timing variability, as compared with tapping with only one finger. Two leading theories propose that the bimanual advantage results from the addition of either sensory (i.e., enhanced feedback) or cognitive (i.e., multiple timekeeper) processes involved in timing. Given that crossing the arms impairs perception of tactile stimuli and modulates cortical activation following tactile stimulation, we investigated the role of crossing the arms in the bimanual advantage. Participants tapped unimanually or bimanually with their arms crossed or uncrossed on a tabletop or in the air. With arms crossed, we expected increased interval timing variance. Similarly, for air tapping, we expected reduced bimanual advantage, due to reduced sensory feedback. A significant bimanual advantage was observed for the uncrossed, but not the crossed posture in tabletop tapping. Furthermore, removing tactile feedback from taps eliminated the bimanual advantage for both postures. Together, these findings suggest that crossing the arms likely impairs integration of internal (i.e., effector-specific) and external (i.e., environment-specific) information and that this multisensory integration is crucial to reducing timing variability during repetitive coordinated bimanual tasks.     

The relation between antisocial personality and the perceived ability to deceive

The current study investigated relations between the perceived ability to deceive and the Dark Triad personality traits in two samples. In study 1, the sample consisted of 1074 participants (329 male, 745 female) aged 17–71 years (M = 22.96, SD = 6.92). Participants completed the perceived ability to deceive scale, in which they were asked to estimate the percentage of people who are worse at lying than they are in a number of situations. Participants also completed the Short-D3 – a measure of the Dark Triad personality traits. As expected, correlational analyses demonstrated that Machiavellianism was most highly correlated with the perceived ability to deceive (r = .41), followed by psychopathy (r = .35), and narcissism (r = .33). These findings were replicated in study 2, which consisted of 1448 undergraduate students (498 males, 947 females, 3 other), aged 18–43 (M = 18.35, SD = 1.77). Study 2 also investigated the association of the Dark Triad and perceived ability to deceive with dimensions of the Big Five model of personality. Implications are discussed.     

The influence of dominant versus non-dominant hand on event and emergent motor timing

It has been hypothesized that timing in tapping utilizes event timing; a clock-like process, whereas timing in circle drawing is emergent. Three experiments examined timing in tapping and circle drawing by the dominant and non-dominant hand. Participants were right-hand dominant college aged males and females. The relationship between variance and the square of the timed interval (the Weber fraction), thought to capture clock-like timekeeping processes, was compared. Furthermore, timing variance was decomposed into a clock and a motor component. The slopes for timing were different for dominant hand tapping and circle drawing, but equal for non-dominant and dominant hand tapping. Negative lag one covariance, consistent with motor implementation variability, was found for non-dominant but not for dominant hand circle drawing (Experiment 1). Practice did not influence this relation (Experiment 2). A significant correlation for clock variability was found between non-dominant hand circle drawing and tapping (Experiment 3). Collectively, these findings indicate that event timing is shareable across hands while emergent timing is specific to an effector. Emergent timing does not appear to be obligatory for the non-dominant hand in circle drawing. We suggest that the use of emergent timing might depend upon the extensive practice experienced by a person's dominant hand.     

Parameters of Aggressive Behavior in a Treatment-Seeking Sample of Military Personnel: A Secondary Analysis of Three Randomized Controlled Trials of Evidence-Based PTSD Treatments

Aggressive behavior is prevalent among veterans of post-9/11 conflicts who have posttraumatic stress disorder (PTSD). However, little is known about whether PTSD treatments reduce aggression or the direction of the association between changes in PTSD symptoms and aggression in the context of PTSD treatment. We combined data from three clinical trials of evidence-based PTSD treatment in service members (N = 592) to: (1) examine whether PTSD treatment reduces psychological (e.g., verbal behavior) and physical aggression, and; (2) explore temporal associations between aggressive behavior and PTSD. Both psychological (Estimate = -2.20, SE = 0.07) and physical aggression (Estimate = -0.36, SE = 0.05) were significantly reduced from baseline to posttreatment follow-up. Lagged PTSD symptom reduction was not associated with reduced reports of aggression; however, higher baseline PTSD scores were significantly associated with greater reductions in psychological aggression (exclusively; ß = -0.67, 95% CI = -1.05, -0.30, SE = -3.49). Findings reveal that service members receiving PTSD treatment report substantial collateral changes in psychological aggression over time, particularly for participants with greater PTSD symptom severity. Clinicians should consider cotherapies or alternative ways of targeting physical aggression among service members with PTSD and alternative approaches to reduce psychological aggression among service members with relatively low PTSD symptom severity when considering evidence-based PTSD treatments.