Movement-Produced Feedback as a Mechanism For The Temporal Anticipation of Motor Responses

That part of the input hypothesis of motor timing behavior which postulates that movement-produced feedback can serve as a mechanism for the temporal anticipation of motor responses was tested. 32 male college Ss temporally anticipated (no preview) the coincidence of a moving pointer with a stationary one and executed the timing response with his right hand while either a high (HFB) or low (LFB) level of movement-produced feedback was indirectly manipulated in the left arm. The HFB group temporally anticipated with greater accuracy than the LFB group which supported that part of the input hypothesis being tested. Apparently, Ss were relying on proprioceptive feedback about the position of their left arm movement to cue the timing response of their right hand.     

Patterns of Human Interlimb Coordination Emerge from the Properties of Non-Linear,Limit Cycle Oscillatory Processes

The present article represents an initial attempt to offer a principled solution to a fundamental problem of movement identified by Bernstein (1967), namely, how the degrees of freedom of the motor system are regulated. Conventional views of movement control focus on motor programs or closed-loop devices and have little or nothing to say on this matter. As an appropriate conceptual framework we offer Iberall and his colleagues’ physical theory of homeokinetics first elaborated for movement by Kugler, Kelso, and Turvey (1980). Homeokinetic theory characterizes biological systems as ensembles of non-linear, limit cycle oscillatory processes coupled and mutually entrained at all levels of organization. Patterns of interlimb coordination may be predicted from the properties of non-linear, limit cycle oscillators. In a set of experiments and formal demonstrations we show that cyclical, two-handed movements maintain fixed amplitude and frequency (a stable limit cycle organization) under the following conditions: (a) when brief and constantly applied load perturbations are imposed on one hand or the other, (b) regardless of the presence or absence of fixed mechanical constraints, and (c) in the face of a range of external driving frequencies from a visual source. In addition, we observe a tight phasic relationship between the hands before and after perturbations (quantified by cross-correlation techniques), a tendency of one limb to entrain the other (mutual entrainment) and that limbs cycling at different frequencies reveal non-arbitrary, sub-harmonic relationships (small integer, subharmonic entrainment). In short, all the above patterns of interlimb coordination fall out of a non-linear oscillatory design. Discussion focuses on the compatibility of these results with past and present neurobiological work, and the theoretical insights into problems of movement offered by homeokinetic physics. Among these are, we think, the beginnings of a principled solution to the degrees of freedom problem, and the tentative claim that coordination and control are emergent consequences of dynamical interactions among non-linear, limit cycle oscillatory processes.     

Reaction Time of Healthy Older Adults Is Reduced While Walking Fast

Attentional requirements of walking at various speeds in older adults were examined. Twenty healthy older adults (69.9?±?2.77?years; 8 males) were asked to walk a distance of 10?m at a self-selected speed as well as 30% quicker and 30% slower. Concurrently, reaction time (RT) was evaluated by having participants respond as fast as possible to randomly presented auditory stimuli. Results reveal that an accelerated walking speed generated faster RT than slow and self-selected speeds, while no difference was found between the latter. Faster RTs during an accelerated walking speed may have been precipitated by the reduced equilibrium demands of the task.     

Gender Roles,Suicide Attempts,and Substance Abuse

In this article, the focus is on a comparison of suicide attempts and substance abuse in the United States. It is argued that suicide attempts and substance abuse may function as psychologically equivalent but gender-specialized forms of self-injurious behaviors. Possible explanations for the gender segregation of suicide attempts and substance abuse are reviewed, and the benefits of crossover theories and treatments are presented.     

The Rise and Decline of the American Asylum Movement in the 19th Century

This paper traces the history of the American public asylum from the 1840s through the late 19th century. The focus is on social factors that contributed to the establishment of public institutions at the urging of reformers, the attempts to model them on the architecture and “moral treatment” offered by the best private institutions, the crowding of the asylums, the growing criticism aimed at the asylums and their superintendents, and the effects of calls for other approaches and for scientific management. Knowledge of the asylum's history may be useful today, as we stand at the crossroads in the treatment of the mentally ill.     

Crafts as Leisure-Based Coping: Craft Makers’ Descriptions of Their Stress-Reducing Activity

The goal of this study was to explore how crafts help women, who do crafting as a leisure activity, cope with stress. This qualitative study is based on the narratives of 15 textile craft makers aged 27–57 who were reporting stress in work and non-work settings. The participants reported that their crafting varied depending on the specific life circumstances they encountered. The analysis revealed that crafts provided recreation, satisfaction, optimism, positive relationships, and support as well as helped participants to cope with negative feelings. Crafts served as a leisure-coping resource and a leisure-based coping strategy.     

It is never the right time: How to help a mother to separate from her young child

In this paper I have described a short-psychotherapy treatment with a mother, a 3-year-old girl, and occasionally a father, over the difficulty in separating and settling down at nursery. The mother's unresolved mourning for the early miscarriage of her second baby was one important factor. She held on to the company and comfort provided by the little girl, who had become the vessel of maternal projections. Filled with Poppy's projections, the mother had also felt unable to withstand and process them. Mr Green was a conflictual element in the family, rather than a supportive husband and father, and Poppy's care and problems were left with the mother. Nine sessions unblocked the situation and allowed Poppy to settle down at a private nursery.     

Psychological Well-Being of Canadian Forces Officer Candidates: The Role of Personality and Coping Strategies

Previous research has suggested that personality influences the coping strategies an individual uses to deal with stressors, which, in turn, influences psychological well-being. This study examines whether coping strategies mediate the relationship between neuroticism and the psychological well-being of Canadian Forces officer candidates undergoing basic training. Only partial evidence was found for the mediating role of coping strategies between neuroticism and psychological well-being. These findings suggest that coping strategies and personality may constitute two independent constructs, both of which have significant contributions to well-being among military personnel.     

Eating Disorder Recovery

Abstract

Qualitative studies addressing the eating disorder recovery process from the client's point of view are notably absent in the literature. For this case study, we conducted a retrospective examination of the recovery process, as recounted by a 37-year-old female who was diagnosed with anorexia nervosa, binge eating/purging subtype at the age of 30. Two in-person interview sessions provided insight into coping skills, multidisciplinary intervention strategies, and long-term treatment challenges. In sum, the client's perspective can add new information to the understanding of eating disorder recovery from feminist and other theoretical frameworks.     

Inter-hemispheric remapping between arm proprioception and vision of the hand is disrupted by single pulse TMS on the left parietal cortex

Parietal cortical areas are involved in sensori-motor transformations for their respective contralateral hemifield/body. When arms of the subjects are crossed while their gaze is fixed straight ahead, vision of the hand is processed by the hemisphere ipsilateral to the arm position and proprioception of the arm by the contralateral hemisphere. It induces interhemispheric transfer and remapping. Our objective was to investigate whether a single pulse TMS applied to the left parietal cortical area would disturb interhemispheric remapping in a similar case, and would increase a simple reaction time (RT) with respect to a control single pulse TMS applied to the frontal cortical area. Two LED were superimposed and located in front of the subjects on the saggital axis. Subjects were asked to carefully fixate on these LED during each trial. The lighting of the red LED was used as a warning signal. Following the green one was illuminated after a variable delay and served as a go-signal. The hand for the response was determined before the start of each trial. TMS was applied to the left parietal, the left frontal cortical areas, or not applied to the subject. Results revealed that: (1) Irrespective of its location, single pulse TMS induced a non-specific effect similar to a startle reflex and reduced RT substantially (15 ms on average) with respect to a control condition without TMS (mean value = 153 ms). (2) Irrespective of TMS, RT were shorter when the right or the left hand was positioned in the right visual hemi-field (i.e. normal and crossed positions respectively). (3) Finally, RT increased when single pulse TMS was applied to the left parietal area and when hands were crossed irrespective of which hand was used. We concluded that interhemispheric sensori-motor remapping was disrupted by a single pulse TMS that was applied to the left parietal cortex. This effect was also combined with some visual attention directed towards the hand located on the right visual hemi-field.