The learning of programmed- and feedback- based processes controlling the production of a positioning response in two dimensions

Two experiments were conducted to investigate the learning of the programmed- and feedback-based processes controlling the production of a slow, self-paced positioning response in two dimensions (direction and extent) in the horizontal plane. Both experiments had two phases: an acquisition phase of 60 trials with KR, followed by a KR withdrawal phase of 20 trials. In Experiment 1, one group (N=15) had visual feedback about the ongoing movement and the other group (N=15) did not. In Experiment 2, one group (N=15) practiced initiating the response in the criterion direction and moving the criterion extent, whereas, the other group (N=15) practiced initiating the response in the criterion direction and moving randomly varied extents. The results of Experiment 1 indicated that the learning of a programmed-based process is a gradually acquired freedom from visual feedback. Experiment 2 revealed that a programmed-based process can be learned independent of a feedback-based process.     

When I's meet: sharing subjective experience with someone from the outgroup

Believing one shares a subjective experience with another (i.e., I-sharing) fosters connections among strangers and alters perceptions of the ingroup and outgroup. In this article, the authors ask whether I-sharing also fosters liking for members of a salient outgroup. Study 1 establishes that I-sharing promotes liking for the other sex, even among people with salient social identities. Study 2 shows that I-sharing promotes liking for a member of the sexual orientation outgroup, whether it occurs before or after group memberships get revealed. Study 3 focuses on salient race categories and looks at the effects of I-sharing versus value-sharing as a function of shared group membership. For those high in existential isolation, I-sharing trumps value-sharing, regardless of the I-sharer's social identity. I-sharing may offer a way of improving attitudes toward outgroup members that still enables people to embrace their differing social identities.     

Interaction Between Visually and Kinesthetically Triggered Voluntary Responses

A voluntary motor response that is prepared in advance of a stimulus may be triggered by any sensory input. This study investigated the combination of visual and kinesthetic inputs in triggering voluntary torque responses. When a visual stimulus was presented alone, subjects produced a fast and accurate increase in elbow flexion torque. When a kinesthetic stimulus was presented instead of the visual stimulus, subjects produced a similar response with a reduced response latency. When a visual stimulus was presented in combination with a kinesthetic stimulus, subjects initiated their responses after either a visual or a kinesthetic response latency, depending on the relative timing of the two stimuli. An analysis of response amplitude suggested that when visual and kinesthetic stimuli were combined, both stimuli triggered a response. The results are more consistent with a simple behavioral model of addition of visual and kinesthetic responses (which predicts that the response to combined stimuli should be the sum of individual responses) than with a model of exclusion of one response (which predicts that the response to combined stimuli should be identical to either the visual or the kinesthetic response). Because addition of visually and kinesthetically triggered responses produced a response with an erroneously large amplitude, it is suggested that visual and kinesthetic inputs are not always efficiently integrated.     

Memory Drum Theory

Two experiments investigated the memory drum theory’s prediction (Henry & Rogers, 1960) that simple reaction time (SRT) increased with the complexity of the response to be initiated. Experiment 1 (N = 9) matched the Experiment 1, Group 1, SRT condition described by Henry and Rogers. Results of Experiment 1 replicated those of Henry and Rogers and indicated that the memory drum theory’s prediction of increased SRT as a function of increased complexity of response was tenable. Experiment 2 (N = 11) tested the effects of anatomical unit, extent, and target size on SRT, premotor time, and motor time. The results supported the contention that alternative explanations for SRT were possible. With complexity constant, increases in anatomical unit lead to increases in SRT, but only in the motor time component which indicated electromechanical rather than neuromotor program delays. It is proposed that the increased motor time could be explained by peripheral events such as the duration maximum torque must be applied by the agonist muscle(s) to generate the angular acceleration required to initiate rapid movement. SRT, premotor time, and motor time increased when target size was reduced from 6.35 cm to .79 cm. The increased premotor time could be a function of the determining of new equilibrium points for the elbow joint during response initiation. No effects on SRT were observed for extent.     

Mirror gazing in body dysmorphic disorder and healthy controls: effects of duration of gazing

Cognitive-behavioural models of body dysmorphic disorder (BDD) suggest that mirrors can act as a trigger for individuals with BDD, resulting in a specific mode of cognitive processing, characterised by an increase in self-focussed attention and associated distress. The aim of the current study was to investigate these factors experimentally by exposing participants with BDD (n = 25) and without BDD (n = 25) to a mirror in a controlled setting. An additional aim was to ascertain the role of duration of mirror gazing in the maintenance of distress and self-consciousness by manipulating the length of gazing (short check vs. long gazing). Findings demonstrated that contrary to what was predicted, not only participants with BDD, but also those without BDD experienced an increase in distress and self-focused attention upon exposure to the mirror. In addition, people without BDD, unlike those with BDD, experienced more distress when looking in the mirror for a long period of time as opposed to a short period of time. This lends some support to the idea that, for people with BDD, gazing in a mirror, regardless of duration, might act as an immediate trigger for an abnormal mode of processing and associated distress, and that this association has developed from past excessive mirror gazing. Further theoretical implications of these findings, as well as subsidiary research questions relating to additional cognitive factors are discussed.     

When shared group membership signifies shared subjective experience: I-sharing and the minimal group paradigm

Ingroup favoritism is pervasive. It emerges even in the minimal group paradigm, where participants are assigned to novel groups based on seemingly insignificant characteristics. Yet many of the grouping schemes used in minimal group research may imply something significant: namely, that ingroup members will share in-the-moment subjective experience, or I-share. Two studies examine the role of inferred I-sharing in the minimal group paradigm. We found that (1) people inferred that they would I-share with ingroup members more than outgroup members; (2) inferred I-sharing increased ingroup favoritism; and (3) inferred I-sharing accounted for this ingroup favoritism. Moreover, expecting to I-share with the outgroup improved participants’ attitudes toward the outgroup. These results converge with other research suggesting that people favor ingroup members, in part, because they expect to I-share with them.     

Surviving the Holidays: Gender Differences in Mortality in the Context of Three Moslem Holidays

Drawing on E. Durkheim's [(1915) The Elementary Forms of the Religious Life, London: George Allen & Unwin] discussion of religious holy-days and on his argument regarding the implications of institutional gender differences [(1897/1951) Suicide, New York: Free Press], it was hypothesized that holy days may affect mortality patterns differentially by gender. The present study focused on Moslems in Israel a very different social and religious context than those that have been studied before. The 1983–1992 data on Israeli Moslem deaths were used. After removing the long-term growth and the seasonal effects, women's mortality was found to be significantly greater in the month of Ramadan than in the month before, and in the two weeks before the feast of Id el-Adhha than in the two weeks after it. For men, mortality was higher in the two weeks after the feast of Id el-Fitr than in the two weeks before it. Religious holidays, then, have a different effect on the pattern of mortality of men and women, reflecting their different roles in the preparation and celebration of the holy day rites.     

Effects of moment of inertia on simple reaction time

Two experiments examined the effect of altering the moment of inertia within an anatomical unit on simple reaction time (SRT), premotor time (PMT), and motor time (MOT) during the initiation of a discrete rapid movement. In Experiment 1 (N = 14), moment of inertia of the forearm was increased with the addition of a weighted cuff fastened around the wrist. In Experiment 2 (N = 7), moment of inertia was altered by the addition of a weighted sleeve to the index finger prior to rapid extension of the digit. Results from both experiments were unequivocal. An increase in the moment of inertia resulted in a significant increase in SRT and MOT but had no significant effect on PMT. Within selected anatomical unites (forearm and index finger), an increase in the moment of inertia does not appear to require additional neuromotor programming time but does influence the overall duration of response initiation.