Influence of experience on postural control: effect of expertise in gymnastics

The authors investigated how expertise in motor skills that require fine postural control, such as gymnastics, influences postural regulation. Gymnasts and nongymnasts performed a postural stabilization task after anterior-posterior destabilization while looking at a target in front of them. The authors recorded and analyzed the center of pressure and the ankle, knee, and hip displacements. Gymnasts were able to react rapidly after destabilization to decrease their center of pressure and the angular movements. Moreover, they used their knees to stabilize posture, whereas the nongymnasts used their hips. These findings suggest that specific postural experience modifies the ability to coordinate and regulate posture. The authors discuss these results from an ecological perspective.     

Links between casino proximity and gambling participation, expenditure, and pathology.

Two studies investigated the relationship between casino proximity and gambling participation, expenditure, and pathology. In Study 1, 8,842 participants were categorized into 1 of 4 driving distances from their home to the nearest casino in the province of Quebec: 0-100 km, 100.01-200 km, 200.01-300 km, or 300.01-981 km. In Study 2, 5,158 participants, who lived within a 100-km driving distance from the Montreal casino, were classified into 1 of 5 equidistant, 20-km driving distances. A survey company interviewed participants regarding their gambling habits. Results indicated a positive link between casino proximity and gambling participation (at the provincial and Montreal levels) and expenditure (at the provincial level only) but no link with the current prevalence rate of probable pathological gambling or of problem gambling. In a setting in which many types of gambling activities are available, casino proximity in itself does not appear to explain the rate of gambling-related problems. It is necessary to continue prospective research on exposure and adaptation theories as potential explanations for the development of pathological gambling.     

Women's eye contact and men's later interest: two field experiments

Previous studies indicated various nonverbal behaviors including eye contact of women are associated with men's approach; however, duration of the eye contact was not tested. In Exp. 1, a female confederate established eye-contact of 3 sec. or 1 sec. with a man when entering a bar. Duration of returned glance was the dependent variable. Analysis showed mean duration of the return glance was statistically shorter in the 1-sec. condition. In Exp. 2, the confederate made eye contact with a man and looked at him less than 1 sec., 2 sec., or 4 sec. The presence versus absence of smile was the dependent variable. Longer duration of eye contact was associated with an increase of smiling.     

A new methodology providing evidence of two distinct processes in the production of hand/foot simultaneous responses

To get simultaneous responses of the hand and the foot, it is mandatory to compensate for the longer peripheral motor conduction delay of the foot. According to the reactive-projective model [Paillard, J. (1948). Quelques données psychophysiologiques relatives au déclenchement de la commande motrice (Some psychophysiological data in relation to the releasing of the motor commands). Année Psychologique, 28-47; Paillard, J. (1990). Réactif et prédictif: deux modes de gestion du geste de la motricité. In V. Nougier, & J. Blanchi (Eds.), Pratiques sportives et modélisation du geste (Sport activity and gesture modeling) (pp. 13-56). Grenoble: Université Joseph-Fourier.] no compensation occurs in a reaction time situation; the hand responds before the foot, which indicates a single motor command released for both effectors. However, in a self-initiated condition, the foot tends to precede the hand suggesting that two distinct motor commands are issued, with the foot command first. Fully self-initiated movements are not usual. It is more usual to prepare a response in anticipation of the time occurrence of a stimulus (e.g., a musician following a conductor, synchronized swimmers emerging together with the music). Therefore, we developed a methodology to test whether the model holds in an anticipation coincidence task. In Experiment 1, the participants were asked to initiate a synchronized hand/foot response when the continuous visual stimulus (constant speed) reaches a target. The results fitted the model. In Experiment 2, anticipation coincidence tasks were performed in three conditions: using the foot (1) or the hand (2) alone, and using the hand and the foot simultaneously (3). Following a constant stimulus protocol, short tones were randomly produced, prior the stimulus, to indicate the participants to inhibit their response. As expected, the frequencies of correct inhibition in each preset period followed a sigmoid curve. The command release is assumed to occur at the biserial point (50% of inhibition). The results confirmed that the motor command of the foot is released sooner than the command of the hand. The hand/foot delay is lower in the simultaneous condition, because the command of the hand is released 40 ms earlier; while the foot command is 10 ms earlier. These data confirm and extend the projective-reactive model to a new category of coordination behavior.     

Biphasic ERK1/2 activation in both the hippocampus and amygdala may reveal a system consolidation of contextual fear memory

There is accumulating evidences to suggest that memory consolidation in some conditions involves two waves of neuronal plastic change. Using two fear conditioning procedures in male C57BL/6J mice, we have recently shown that consolidation of the foreground contextual fear memory required two waves of ERK1/2 activation in hippocampal CA1, while consolidation of cue conditioning was only associated with the early phase of activation. The present experiment further showed that this bi-phasic pattern of ERK1/2 activation was not restricted to hippocampal CA1, but could also be observed in other fear memory-related brain areas. The unpaired conditioning procedure (context in foreground) induced two waves of ERK1/2 activation in hippocampal CA1 and CA3, as well as in the LA and BLA nuclei of the amygdala. In contrast, the paired conditioning procedure (context in background) led to a transient early phase only in hippocampal CA1 and LA. In addition, ERK1/2 phosphorylation in the hippocampus was found to correlate with that in the amygdala nuclei specifically after the unpaired procedure. Taken together, our data suggest that the observed biphasic pattern of neuronal plastic events may reflect the interplay between hippocampal and amygdala activity-dependent plasticity critical for the system consolidation of contextual fear memory.     

Induced Reminiscence of Love and Chivalrous Helping

This study tested the effect of semantically-induced thoughts of love on chivalrous helping. A field setting of four hundred and one participants was divided into two groups. One group was interviewed and asked to retrieve the memory of a love episode, and the second group, the control group, was asked to retrieve a piece of music that they love. The two groups encountered another confederate, who inadvertently lost a stack of compact discs when they neared each other. The results demonstrated that participants were more helpful when they were male, when the person in need of help was female, and when they were induced to retrieve the memory of a love episode.     

Relationship between manual preferences for object manipulation and pointing gestures in infants and toddlers

The aim of this study was to measure the pattern of hand preferences for pointing gestures as a function of object‐manipulation handedness in 123 infants and toddlers (10–40 months). The results showed that not only right‐handers but also left‐handers and ambidextrous participants tended to use their right hand for pointing. There was a significant correlation between manual preferences and pointing lateralization. Further analyses showed that the correlation between these two indexes was at its strongest during two key phases of language development (i.e. vocabulary spurt and syntax improvement) and weakened to become nonsignificant in the interim. These findings support the view that humans have a specialized area for communicative gestures and language in the left cerebral hemisphere that may be independent of the system controlling the purely motor functions of hand use.