Rowing together: Interpersonal coordination dynamics with and without mechanical coupling

Although most research on interpersonal coordination focuses on perceptual forms of interaction, many interpersonal actions also involve interactions of mechanical nature. We examined the effect of mechanical coupling in a rowing task from a coupled oscillator perspective: 16 pairs of rowers rowed on ergometers that were physically connected through slides (mechanical coupling condition) or on separate ergometers (no mechanical coupling condition). They rowed in two patterns (in- and antiphase) and at two movement frequencies (20 and 30 strokes per minute). Seven out of sixteen pairs showed one or more coordinative breakdowns, which only occurred in the antiphase condition. The occurrence of these breakdowns was not affected by mechanical coupling, nor by movement frequency. For the other nine pairs, variability of steady state coordination was substantially lower in the mechanical coupling condition. Together, these results show that the increase in coupling strength through mechanical coupling stabilizes coordination, even more so for antiphase coordination.     

Self-reported walking difficulty and knee osteoarthritis influences limb dynamics and muscle co-contraction during gait

Knee osteoarthritis (OA) gait is characterized by simultaneous flexor and extensor use, or co-contraction. Co-contraction can stabilize and redirect joint forces. However, co-contraction can push and pull on the femur and tibia that exacerbate OA symptoms and make walking difficult. Such movements are quantifiable by limb dynamics (i.e., linear acceleration and jerk); thus, this study examines limb dynamics and its relationship with co-contraction and OA related walking difficulty.Three groups of age-and-sex-matched subjects with and without OA and walking difficulty (N = 13 per group) walked with electromyography (EMG) on the knee extensors and flexors and inertial measurement units (IMUs) at the femur and tibia. We calculated co-contraction from antagonistic EMG signals and linear acceleration and its derivative jerk from IMUs. We determined group differences using one-way ANOVAs, nonparametric equivalence, and effect sizes, and main and interaction effects of walking difficulty with regression modeling.Medium effect sizes and differences for femoral acceleration (d = 0.64; P = .02) and jerk (d = 0.51; P = .01) were observed between with and without knee OA. Medium to large effect sizes (r = 0.33 to 0.51 and d = 0.81 to 0.97) and differences (P = .01 to 0.05) for tibial acceleration and jerk were obsevered between with and without walking difficulty. Walking difficulty moderated the relationship between tibial jerk and co-contraction (p < .05).Tibial jerk differences were observed based on walking difficulty. The significant interaction effect suggested that walking difficulty explained the relationship between limb dynamics and co-contraction. Perhaps co-contraction levels used by those with knee OA and no walking difficulty are optimal as compared to those with walking difficulty.     

JOURNEY OF THE UNIVERSE: WEAVING SCIENCE WITH THE HUMANITIES

This article discusses Journey of the Universe as a project that consists of a film, book, conversation series, online classes, and a website. It describes how the creators worked to integrate science and humanities, not privilege or elevate science. It refutes arguments made in Lisa Sideris's Consecrating Science: Wonder, Knowledge, and the Natural World that suggest that Journey overlooks religion and distorts wonder. The article observes that Journey does not dismiss religion but includes it in explicit ways. It does not dictate wonder; it evokes wonder. In short, Journey is a living or functional cosmology with implications for mutually enhancing human–Earth relations.     

A Direct-Learning Approach to Acquiring a Bimanual Tapping Skill

The theory of direct learning (D. M. Jacobs &; C. F. Michaels, 2007 Jacobs, D. M., &; Michaels, C. F. (2007). Direct learning. Ecological Psychology, 19, 321–349.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) has proven useful in understanding improvement in perception and exploratory action. Here the authors assess its usefulness for understanding the learning of a motor skill, bimanual tapping at a difficult phase relation. Twenty participants attempted to learn to tap with 2 index fingers at 2 Hz with a phase lag of 90° (i.e., with a right-right period of 500 ms and a right-left period of 125 ms). There were 30 trials, each with 50 tapping cycles. Computer-screen feedback informed of errors in both period and phase for each pair of taps. Participants differed dramatically in their success. Learning was assessed by identifying the succession of attractors capturing tapping over the experiment. A few participants’ attractors migrated from antiphase to 90° with an appropriate period; others became attracted to a fixed right-left interval, rather than phase, with or without attraction to period. Changes in attractor loci were explained with mixed success by direct learning, inviting elaboration of the theory. The transition to interval attractors was understood as a change in intention, and was remarkable for its indifference to typical bimanual interactions.     

A Case Study Demonstrating Reduction of Aggressive Client Behaviors Using the Neuro-Occupation Model: Addressing Professional Burnout through Nonlinear Thinking

This single case study suggests that mental health practitioners adopt nonlinear modes of thinking within the neuro-occupation model to avoid professional burnout. Accordingly, the elimination of severely aggressive behavior of an institutionalized client was reviewed following an intervention using the model. Provided with new opportunities, the client self-extinguished aggressive interactions, reinstated social behaviors, and expanded occupations. Accepting clients as their own change agents limits our role to facilitators and reframes service delivery in mental health, which argues for comparison studies that measure reduced burnout in occupational therapists using the model.     

An atomistic modelling and statistical analysis study of crack–void interaction in Aluminum

The interaction between a brittle crack and pre-existing void in front of the crack tip was studied in the realm of molecular dynamics simulations at the nanoscale in face centred cubic Al within the framework of embedded-atom method. The results provide corroborative evidence of the fact that presence of a void in front of a running crack deters further crack growth. By performing an extensive series of simulations with different void sizes and crack-void distances coupled with statistical analysis, it has been found that (1) major role of voids is to decrease the fracture stress with increasing void size, in addition to slight increase in strain at which the crack growth occurs and the consequent strain to fracture, (2) fracture stress for a constant void size follows a sinusoidal distribution by varying the crack-void distance and (3) it is the void size that is most crucial in dictating the fracture properties of the material, rather than the void placement.     

Social Anxiety and Social Surrogacy in College Roommate Relationships

The social surrogate hypothesis proposes that people with higher social anxiety (HSA) recruit others to accompany them into social situations. We tested this hypothesis with college roommates using both hypothetical (Study 1) and retrospective (Study 2) measures, while assessing roommate's perceptions of recruitment and how social surrogacy might influence liking between roommates. Across two studies, we found that HSA participants were less likely to enter social situations alone (i.e. higher conditional entry); however, HSA was related to recruitment only when participants considered hypothetical scenarios, not when recruitment was assessed globally or retrospectively. There was little evidence that HSA participants' roommates were aware of these behaviours, although there was preliminary evidence that less social anxiety might increase liking when roommates perceived more conditional entry. We also found preliminary evidence that social anxiety may be negatively related to liking when participants were less likely to recruit an alternate surrogate if their roommate was unavailable. Taken together, these preliminary findings emphasize the importance of studying the surrogacy process from an interpersonal/dyadic perspective and using methods that will differentiate between anticipated (which may be assessed by hypothetical scenarios) and enacted recruitment behaviours. Copyright © 2017 European Association of Personality Psychology     

Exploring counsellor perceptions of the impact of counselling supervision on clients

This qualitative study explores counsellors’ experiences and perceptions of how counselling supervision impacts upon their clients. Data collection combined open‐ended questionnaires (n = 13) and semi‐structured interviews (n = 6). The findings indicate that supervision impacts client work both helpfully and unhelpfully. Areas that emerged as having the most direct impact on client work were the counselling relationship dynamics and self‐awareness, professional development, emotional support, clients not discussed in supervision and the quality of the supervisory relationship. Congruence and confidence were the most direct link between supervision and client work.     

Preserving integrity against colonization

Genuine reconciliation between first- and third-person methodologies and knowledge requires respect for both phenomenological and scientific epistemologies. Recent pragmatic, theoretical, and verbal attempts at reconciliation by cognitive scientists compromise phenomenological method and knowledge. The basic question is thus: how do we begin reconciling first- and third-person epistemologies? Because life is the unifying concept across phenomenological and cognitive disciplines, a concept consistently if differentially exemplified in and by the phenomenon of movement, conceptual complementarities anchored in the animate properly provide the foundation for reconciliation. Research by people in neuroscience and in dynamic systems theory substantiate this thesis, providing fundamental examples of conceptual complementarity between phenomenology and science.