Effects of Pointing Rate and Availability of Visual Feedback on Visual and Proprioceptive Components of Prism Adaptation

The withdrawal of vision of the arm during a manual aiming task has been found to result in a large increase in aiming error, regardless of the amount of practice in normal vision before its withdrawal. In the present study, the authors investigated whether the increase in error reflects the domination of visual afferent information over the movement representation developed during practice to the detriment of other sources of afferent information or whether it reflects only transformation errors of the location of the target from an allocentric to an egocentric frame of reference. Participants (N = 40) performed aiming movements with their dominant or nondominant arm in a full-vision or target-only condition. The results of the present experiment supported both of those hypotheses. The data indicated that practice does not eliminate the need for visual information for optimizing movement accuracy and that learning is specific to the source or sources of afferent information more likely to ensure optimal accuracy during practice. In addition, the results indicated that movement planning in an allocentric frame of reference might require simultaneous vision of the arm and the target. Finally, practice in a target-only condition, with knowledge of results, was found to improve recoding of the target in an egocentric frame of reference.     

Visual Information and the Control of Reaching in Children: A Comparison Between Children With and Without Developmental Coordination Disorder

Three experiments were performed on reach and grasp in 9- to 10-year-old children (8 controls and 8 with developmental coordination disorder [DCD]). In normal reaching, children in the DCD group were less responsive to the accuracy demands of the task in controlling the transport component of prehension and spent less time in the deceleration phase of hand transport. When vision was removed as movement began, children in the control group spent more time decelerating and reached peak aperture earlier. Children in the DCD group did not do that, although, like the control group, they did increase grip aperture in the dark. When depth cues were reduced and only the target or only the target and hand were visible, children in the control group used target information to maintain the same grip aperture in all conditions, but DCD children behaved as if the target was not visible. Throughout the studies, the control group of 9- to 10-year-olds did not produce adult-like adaptations to reduced vision, suggesting that they had not yet attained adult-like integration of sensory input. Compared with control children, children with DCD did not exhibit increased dependence on vision but showed less recognition of accuracy demands, less adaptation to the removal of vision, and less use of minimal visual information when it was available.     

Observational Learning and the Role of Confinement in Pigeons: Suppression of Learning as a Function of Observing the Performance of a Conspecific

Observational learning of a successive discrimination problem by pigeons was studied using conspecifics as models responding for either contingent or noncontingent reinforcement. We found that observation of these models was associated with poorer performance on subsequent testing than was shown by a control group that learned without first observing conspecifics' performance. No significant difference was found between subjects without observational experience and another control group that was confined in the observation apparatus and observed an empty chamber only.     

Weight maintenance: Self-regulatory factors underpinning success and failure

Objectives: To investigate the differences in the contributing factors involved in weight maintenance success and failure.

Design: Semi-structured interviews were conducted with both successful and unsuccessful weight maintainers. Eighteen participants were recruited (16 women), nine of who had lost 10% of their body weight and maintained this weight for a minimum of 12?months (Maintainers), and nine individuals who met the above criteria for weight loss but had subsequently regained their weight (Regainers). A thematic analysis was employed to compare the differences between the two groups.

Results and conclusions: Two main themes highlighted the differences between the two groups, these were: goal regulation and self-control. Within these overarching themes, successful weight maintenance was related to the following subthemes: long-term, realistic goal setting, consistent use of routines and self-monitoring, avoiding deprivation and effective coping skills. Unsuccessful maintenance was related to short-term unrealistic goal setting, inconsistent routines and self-monitoring, experiencing deprivation and poor coping skills. These factors are explained in terms of the interrelationships that they have on one another and their subsequent impact on weight maintenance success or failure.     

Exploring patient perspectives of prediabetes and diabetes severity: a qualitative study

Abstract

Objective: This qualitative study sought to identify and describe patients’ variant perceptions of disease severity after receiving a type 2 diabetes (T2DM) or prediabetes (preDM) diagnosis.

Design: Researchers interviewed 29 patients from two US medical centers to ascertain perceptions of severity. We used the constant comparative method from a grounded theory approach to identify themes from patients’ perspectives that inform their disease severity. This approach was used to help translate research to practice and ultimately identify intervention strategies informed by authentic experiences of preDM and T2DM patients.

Results: Perceptions of disease severity fell into two groups: high and low severity. Patients diagnosed with T2DM and preDM emerged in both groups and were comparative in terms of sample size, gender, and ethnic diversity. Several factors contributed to patients’ beliefs, including what they were told about the disease, observations from experiences within their own social network, and information from formal diabetes classes and their own research. The two perspectives diverged when patients described how their belief was informed by three thematic properties or personal factors: (i) fears; (ii) clinician communication; and (iii) social comparisons.

Conclusions: Beliefs about severity are influenced by patients’ fears, interactions with clinicians, and experiences within their social networks. These findings show that when interacting with patients with T2DM or preDM, clinicians should elicit patient perceptions of disease severity so they may then tailor the discussion to address these perceptions and help patients grasp the severity of these conditions.     

The effects of threatened social evaluation of the physique on cortisol activity

Social self preservation theory asserts that situations high in social-evaluative threat elicit increases in cortisol, a hormone released by the hypothalamic-pituitary-adrenal axis. Most tests of the theory have examined threats associated with social evaluation of a performance. Two experiments examined the effects of threatened social evaluation of one's physique. In Experiments 1 (n?=?50) and 2 (n?=?40), participants allocated to an experimental (threat) condition had significantly higher post-manipulation cortisol than participants in a control (no threat) condition. In Experiment 1, perceptions of social-evaluative threat were significantly correlated with post-manipulation cortisol levels. These results suggest that the threatened social evaluation of one's body can activate the cortisol response. Women who frequently experience such threats may be at increased risk for a variety of health conditions associated with chronic cortisol exposure.     

In the Wake of Don't Ask Don't Tell: Suicide Prevention and Outreach for LGB Service Members

It is estimated that lesbian, gay, and bisexual (LGB) individuals are three to five times more likely to attempt suicide than their heterosexual counterparts. Factors linked to increased LGB suicide risk are overt and covert discrimination, internalized oppression, nondisclosure of sexual orientation, and lack of adequate social support. As the U.S. military adjusts to the repeal of Don't Ask Don't Tell (DADT), it will be imperative to understand and support service people who are struggling with many of these same issues. This article explores factors linked to suicidality and provides education for professionals working with LGB service people. Emphasis is placed on strategies for the provision of support and suicide prevention for members of this population.     

The Impact of Benefit Finding and Leadership on Combat-Related PTSD Symptoms

Benefit finding and unit leadership have been identified as buffers against the negative effects of combat exposure on posttraumatic stress disorder (PTSD) symptoms. However, little is known about how these different buffers work together to protect military personnel from the negative effects of combat. We examined benefit finding and leadership as buffers of the combat–PTSD symptoms link in a sample of recently returned combat veterans (N?=?583). Results revealed that when higher levels of noncommissioned officer (NCO) leadership and benefit finding (BF) were reported, fewer PTSD symptoms were endorsed. Additionally, BF buffered the relationship between combat stress and PTSD symptoms, but only under conditions of supportive officer leadership. Implications of these findings for military settings are discussed.