Postural coordination modes considered as emergent phenomena.

The coordination of multiple body segments (torso and legs) in the control of standing posture during a suprapostural task was studied. The analysis was motivated by dynamical theories of motor coordination. In 2 experiments it was found that multisegment postural coordination could be described by the relative phase of rotations around the hip and ankle joints. The effective length of the feet, the height of the center of mass, and the amplitude of head motions in a visual tracking task were varied. Across these variations, 2 modes of hip-ankle coordination were observed: in-phase and anti-phase. The emergence of these modes was influenced by constraints imposed by the suprapostural tracking task, supporting the idea that such tasks influence postural control in an adaptive manner. Results are interpreted in terms of a dynamical approach to coordination in which postural coordination modes can be viewed as emergent phenomena.     

Event-related brain potentials reflect traces of echoic memory in humans

In sequences of identical auditory stimuli, infrequent deviant stimuli elicit an event-related brain potential component called mismatch negativity (MMN). MMN is presumed to reflect the existence of a memory trace of the frequent stimulus at the moment of presentation of the infrequent stimulus. This hypothesis was tested by applying the recognition-masking paradigm of cognitive psychology. In this paradigm, a masking sound presented shortly before or after a test stimulus diminishes the recognition memory of this stimulus, the more so the shorter the interval between the test and masking stimuli. This interval was varied in the present study. It was found that the MMN amplitude strongly correlated with the subject’s ability to discriminate between frequent and infrequent stimuli. This result strongly suggests that MMN providesa measure for a trace of sensory memory, and further, that with MMN, this memory can be studied without performance-related distortions.     

Coping with neck and low back pain in the general population.

This study had 2 objectives: (a) to assess the psychometric properties of the Pain Management Inventory (PMI; G. K. Brown & P. M. Nicassio, 1987) with individuals in the general population with neck or low back pain, and (b) to assess the relationship between pain severity and coping. Data were taken from a mailed survey of a random sample of adults residing in Saskatchewan, Canada. Results validated the 2-factor structure of the PMI and provided evidence for the internal consistency of the coping subscales. Regression analyses revealed that passive coping was associated with being married, greater pain severity, depression, and poor health. Active coping was associated with female gender, higher education, less depression, good health, and frequent exercise. This study provides psychometric data to support the use of the PMI and information about factors associated with use of active and passive coping strategies in pain sufferers.     

Influence of perceived emotion and gender on social motor coordination

Theorists have long postulated that facial properties such as emotion and sex are potent social stimuli that influence how individuals act. Yet extant scientific findings were mainly derived from investigations on the prompt motor response upon the presentation of affective stimuli, which were mostly delivered by means of pictures, videos, or text. A theoretical question remains unaddressed concerning how the perception of emotion and sex would modulate the dynamics of a continuous coordinated behaviour. Conceived in the framework of dynamical approach to interpersonal motor coordination, the present study aimed to address this question by adopting the coupled-oscillators paradigm. Twenty-one participants performed in-phase and anti-phase coordination with two avatars (male and female) displaying three emotional expressions (neutral, happy, and angry) at different frequencies (100% and 150% of the participant's preferred frequency) by executing horizontal rhythmic left-right oscillatory movements. Time to initiate movement (TIM), mean relative phase error (MnRP), and standard deviation of relative phase (SDRP) were calculated as indices of reaction time, deviation from the intended pattern of coordination, and coordination stability, respectively. Results showed that in anti-phase condition at 150% frequency, MnRP was lower with the angry and the female avatar. In addition, coordination was found to be more stable with the male avatar than the female one when both displaying neutral emotion. But the happy female avatar was found to elicit more stable coordination than the neutral female avatar. These results implied that individuals are more relaxed to coordinate with the female than the male, and the sensorimotor system becomes more flexible to coordinate with an angry person. It is also suggested social roles influence how people coordinate, and individuals attend more to interact with a happy female. In sum, the present study evidenced that social perception is embodied in the interactive behaviour during social interaction.     

The Development of Physical Aggression from Toddlerhood to Pre-Adolescence: A Nation Wide Longitudinal Study of Canadian Children

The objectives of the study were to model the developmental trajectories of physical aggression (PA) from toddlerhood to pre-adolescence and to identify risk factors that distinguish typical (normative) from atypical developmental patterns. Ten cohorts of approximately 1,000 children (n = 10,658) drawn form a nationally representative (Canadian) sample were followed over 6 years. Using a group based trajectory approach, we identified three groups of children with distinct developmental trajectories between 2 and 11 years of age. One third of the children (31.1%) followed a low desisting trajectory, reflected in infrequent use of PA in toddlerhood and virtually no PA by pre-adolescence. The majority of children (52.2%) followed a moderate desisting trajectory, reflected in occasional use of PA in toddlerhood and infrequent use by pre-adolescence. One sixth of the children (16.6%) followed a high stable trajectory of PA. Multivariate logistic regression indicated that children in the high PA trajectory group were more likely to be boys (OR: 1.67; CI: 1.5–1.87), from low income families (OR: 1.4; CI; 1.27–1.67), from families where the mother had not completed high school (OR: 1.20; CI: 1.05–1.38) and who reported using hostile/ineffective parenting strategies (OR: 1.16; CI: 1.14–1.18). In sum, the results indicate that the typical developmental pattern of PA was one of occasional and declining use over time. However, about one sixth of children, mostly boys from disadvantaged families, exhibited an atypical developmental pattern reflected in more frequent and stable use of PA. The results suggest that most children learned relatively well to inhibit PA by the end of childhood and that a minority failed to do so. Family risks traditionally found to be associated with antisocial behaviors during adolescence appear to interfere with the socialization of PA during early and middle childhood.     

Dimensionality and the dynamics of human unstable equilibrium

Maintaining an unstable equilibrium requires that multiple joints be coordinated so that the center of mass is kept above the base of support. The authors' aim in the present study was to discover the underlying dynamics of local (foot, hip, or head) and global (center of mass) components involved in balance control and how those dynamics are affected by changes in the available information. Participants (N = 6) had to maintain their balance on an unstable platform. Using dimensional analyses (largest Lyapunov exponent and correlation dimension), the authors examined the active degrees of freedom involved in balance control. Results indicated a similarity in dimension between local (joints) and global (center of mass) components, between a fixed point and a limit cycle. The behavior of the center of mass was found to be more predictable than the behavior of its local constituents. In addition, the available visual information affected the predictability of the postural behavior, which suggests that vision is used in the stabilization of the low-dimensional dynamics underlying balance control.     

Examination of adolescents' negative thoughts, depressive mood, and family environment.

The focus of this study was the relationship among adolescents' negative thoughts, depressive mood, and family environment. Three hundred eleven students (aged 16 and 17 years) in public and private schools served as subjects. They were administered the Family Environment Scale, the Automatic Thoughts Questionnaire, and the Beck Depression Inventory. Family cohesion was found to be related to the degree of negative thoughts and depressive mood of the adolescents, but perceived control within the family was not.     

Potential moral stigma and reactions to sexually transmitted diseases: evidence for a disjunction fallacy

Five experiments demonstrate how potential moral stigma leads people to underplay their susceptibility to sexually transmitted diseases (STDs) and dampens their interest in getting tested. After adding unprotected sex to a list of otherwise innocuous possible vectors for a disease, the authors found that infected people were perceived to be less moral (Experiment 1a), and individuals believed that if they had the disease, others would see them as less moral too (Experiment 1b). Adding this stigmatized vector also reduced reported testing intentions (Experiment 2) and perceived risk of exposure (Experiment 3)--a disjunction fallacy because adding a potential cause reduced estimated likelihood, in violation of basic probability rules. Finally, the authors replicated the effect in a computer virus analog (Experiment 4) and showed that it did not result from simply knowing that one has not engaged in the stigmatized behavior. Results suggest that avoidance of potential stigma can have dramatic health consequences, both for an individual's health decision and for health policy.     

The timing of appraisals

The appraisal process consists of the subjective evaluation that occurs during an individual's encounter with significant events in the environment, determining the nature of the emotional reaction and experience. Placed in the context of appraisal theories of emotion-elicitation and differentiation, the aim of the present research was to test empirically the hypothesis that the intrinsic pleasantness evaluation occurs before the goal conduciveness evaluation. In two studies, intrinsically pleasant and unpleasant images were used to manipulate pleasantness, and a specific event in a Pacman-type videogame was used to manipulate goal conduciveness. Facial EMG was used to measure facial reactions to each evaluation. As predicted, facial reactions to the intrinsic pleasantness manipulation were faster than facial reactions to the goal conduciveness manipulation. These results provide good empirical support for the sequential nature of the appraisal process.     

Reducing the effects of the stereotype threat that girls perform less well than boys in mathematics: the efficacy of a mixed debate in a real classroom situation

The present research aims at testing the effects of the mixed debate in a classroom situation on reducing the stereotype threat according to which girls perform less well than boys in mathematics. Our work is based on studies conducted on stereotype threat (Steele and Aronson in J Person Soc Psychol 69:797–811. https://doi.org/10.1037//0022-3514.69.5.797, 1995), as well as those aiming to reduce the impact of stereotype threat on stereotyped populations (Huguet and Régner in J Educ Psychol 99(3):545–560. https://doi.org/10.1037/0022-0663.99.3.545, 2007; Marx and Roman in Personal Soc Psychol Bull 28:1185–1197. https://doi.org/10.1177/01461672022812004, 2002; Spencer et al. in J Exp Soc Psychol 35:4–28. https://doi.org/10.1006/jesp.1998.1373, 1999). We will more particularly study Smith and Postmes' (Br J Soc Psychol 50(1):74–98. https://doi.org/10.1348/014466610X500340, 2010) work on small group discussions used to reduce the influence of the threat. Results indicate that having a debate as such reduces the impact of the stereotype threat in girls. Possible interpretations of the results and future research perspectives will be put forward.