Hierarchical control of rapid movement sequences

Are movement sequences executed in a hierarchically controlled fashion? We first state explicitly what such control would entail, and we observe that if a movement sequence is planned hierarchically, that does not imply that its execution is hierarchical. To find evidence for hierarchically controlled execution, we require subjects to perform memorized sequences of finger responses like those used in playing the piano. The error data we obtain are consistent with a hierarchical planning as well as execution model, but the interresponse-time data provide strong support for a hierarchical execution model. We consider three alternatives to the hierarchical execution model and reject them. We also consider the implications of our results for the role of timing in motor programs, the characteristics of motor buffers, and the relations between memory for symbolic and motor information.     

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Stressed organizations and organizational stressors: A systemic analysis of workplace injury

The experiences of five injured workers from one workplace which had been identified as having a very poor workers' compensation claims experience were analyzed using a systemic theory framework. It was predicted that the fundamental stress-producing conflict between safety and profit that exists in industry between workers and their employers is exacerbated when a worker is injured; furthermore, the degree of stress experienced by both the injured worker and the employer is related to the impact of the injury on the organization and on the productivity of the workplace. The increased stress in both the injured worker and the employer results in increased rigidity in responding to the change or threat in the organization caused by workplace injury. A systemic approach to rehabilitation was recommended in which the employer as well as the injured worker were viewed as clients who required varying levels of support and intervention in managing workplace injury.     

Minimal Requirements for the Emergence of Learned Signaling

The emergence of signaling systems has been observed in numerous experimental and real‐world contexts, but there is no consensus on which (if any) shared mechanisms underlie such phenomena. A number of explanatory mechanisms have been proposed within several disciplines, all of which have been instantiated as credible working models. However, they are usually framed as being mutually incompatible. Using an exemplar‐based framework, we replicate these models in a minimal configuration which allows us to directly compare them. This reveals that the development of optimal signaling is driven by similar mechanisms in each model, which leads us to propose three requirements for the emergence of conventional signaling. These are the creation and transmission of referential information, a systemic bias against ambiguity, and finally some form of information loss. Considering this, we then discuss some implications for theoretical and experimental approaches to the emergence of learned communication.     

Allocentric-heading recall and its relation to self-reported sense-of-direction

A sense of direction (SOD) computes the body's facing direction relative to a reference frame grounded in the environment. The authors report on three experiments in which they used a heading-recall task to tap the functioning of a SOD system and then correlated task performance with self-reported SOD as a convergent test of the task's construct validity. On each heading-recall trial, the participant judged the photographer's allocentric heading when photographing a pictured outdoor scene. Participants were tested over the full range of SOD ratings in Experiment 1, and in Experiments 2 and 3 heading-recall at the SOD extremes was tested. In all experiments, there was wide variability in heading-recall accuracy that covaried with self-rated SOD. Parametric manipulation of various task parameters revealed some likely functional properties of the SOD system. The results support the psychological reality of a SOD system and further indicate that there are large individual differences in the efficacy with which the system functions.     

Modern prejudice toward gay men and lesbian women: assessing the viability of a measure of modern homonegative attitudes within an Irish context

The authors examined the psychometric properties of the gay and lesbian versions of the Modern Homonegativity Scale (MHS-G and MHS-L) in samples of heterosexual Irish university students (Ns=179 and 353). Confirmatory factor analyses revealed that the MHS-G and MHS-L were unidimensional and factorially distinct from a well-established measure of old-fashioned homonegativity (Attitudes Toward Lesbians and Gay Men Scale [ATLG]). Alpha coefficients for both versions of the MHS were good (range = .81 to .86), with 95% confidence intervals suggesting that unsatisfactory levels of scale score reliability (i.e., alpha values < .70) were relatively implausible. As hypothesized, participants' level of modern homonegativity correlated positively with their levels of old-fashioned and modem racism, patriotism, nationalism, religious fundamentalism, social dominance, and perceived political conservatism. The authors also observed a substantial inverse correlation between modern prejudice toward sexual minorities and support for their human rights. Finally, a series of multiple regression analyses indicated that, despite their interrelatedness, modern and old-fashioned homonegativity, particularly as they pertain to gay men, possess differential predictors. Limitations of the current series of studies and the need to conduct further research on attitudes toward sexual minorities within an Irish context are also discussed.     

Accuracy and bias in the perception of the partner in a close relationship

Partners in close relationships can be both accurate and biased in their perceptions of each other. Moreover, sometimes a bias can lead to accuracy. The authors describe a paradigm for the simultaneous measurement of accuracy and bias in 2-person relationships. One prevalent bias in close relationships is assumed similarity: Does the person think that his or her partner sees the world as he or she does? In a study of 238 dating and married heterosexual couples, the authors found evidence for both bias and accuracy: the bias effects were considerably stronger, especially when the measure was linked to the relationship. They found little or no evidence for gender differences in accuracy and bias.