Effects of surface texture on weight perception when lifting objects with a precision grip

In this paper, we show that, when lifting an object using a precision grip with the distal pads of the thumb and index finger at its sides, the perceived weight depends on the object’s surface texture. The smoother the surface texture, the greater the perceived weight. We suggest that a smoother object is judged to be heavier because the grip force, normal to the surface, required to prevent it from slipping is greater. The possibility of there being an influence of surface texture per se is excluded by a second experiment that employed a variant of the precision grip in which the thumb supports the weight of the object from underneath. With the grip oriented in this way, there is no need to match grip force to surface texture and, under these conditions, there is no effect of surface texture on weight perception. In the first two experiments, the test and comparison weights were lifted successively by the same hand. In a third experiment, the effect of surface texture was replicated for sequential lifts made with separate hands. Thus, the effect is not restricted to comparisons made with the same hand.     

Sexual responding of “nonrapists” to aggressive sexual themes: Normative data

The present study presents data relevant to the sexual responding to aggressive cues of a large sample of nonrapist males recruited from the community. Two hundred three subjects received physiological assessment of sexual arousal to heterosexual and rape stimuli. Results indicated that under instructions not to interfere with sexual responding, approximately 80% of the nonrapists would be correctly classified, which was significantly different from chance. However, under instructions to suppress arousal, classification was no better than chance. The rape index was not related to age, socioeconomic status, sexual experience, or amount of arousal shown in the laboratory. However, there was a small but significant relationship to IQ. Overall, the data suggest that for instructions not to interfere with responding, the error rate seen in this larger-scale sample was equivalent to that in previous studies using smaller normative samples and that classification in general is not biased by the subject characteristics measured in this study.Portions of this project were supported by USPHS Grant MH-34030-02 from the Center for the Studies of Crime and Delinquency and by Tennessee Department of Mental Health and Mental Retardation Research Contract ID-0783 to the Department of Psychiatry.     

Psychology,progress, and the problem of reflexivity: A study in the epistemological foundations of psychology

Buss's thesis that, throughout the history of psychology, psychological theories have alternated between two contradictory models of human nature is examined and supported. One model sees humans as actively constructing themselves; the other model sees humans as constructed from the outside. The thesis that the inherent reflexive quality of psychological inquiry is the cause of this alternation is then examined. Three different hypotheses as to how “reflexivity” might explain this alternation are offered. Finally, brief attention is given to the question of whether psychology can be seen as progressing if it is as philosophically indecisive as the analysis suggests.     

Coming to grips with weight perception: effects of grasp configuration on perceived heaviness

We investigated how changes in grasp configuration affect perceived heaviness in a weight discrimination task in which participants compared the weights of a series of test objects with the weight of a reference object. In different experiments, we varied the width of the grasp, the number of digits employed, the angle of the grasp surface, and the size of the contact area between the digits and the object. We show that objects are perceived to be lighter when lifting with (1) a wide grip in comparison with a narrow grip, (2) five digits in comparison with two digits, and (3) a large contact area in comparison with a small contact area. However, the angle of the contact surfaces did not influence perceived weight. We suggest that changes in central motor commands associated with grasp differences may influence perceived weight, at least under some conditions.     

Gender bias in the diagnosis of personality disorders: the roles of base rates and social stereotypes

In all three studies described in this article, novices were trained to associate traits from the DSM-IV Cluster B personality disorder categories with four letters of the alphabet. Novices were also taught various gender associations (i.e., "base rate" information) with the categories (none, stereotype-consistent, or stereotype-inconsistent). Results showed that when no gender associations were taught (Study I), case gender did not affect ratings of case vignettes. When associations were consistent with social stereotypes (Study II), case gender influenced ratings in the expected direction. When associations were the opposite of social stereotypes (Study III), only the ratings for narcissistic and histrionic were affected. Across the three studies, these results suggested that subjects rated cases in accordance with known "base rates," but that the correspondence between base rates and stereotypic associations affected the consistency and magnitude of this base rate effect.     

Rereading the Kripkean Intuition on Reference

Saul Kripke's thought experiments on the reference of proper names target the theory that the properties which identify a term's referent are the subject of an implicit agreement. Recently, survey versions of the experiments have been thought to show that intuitions about reference are culturally contingent. Proposing a revisionary interpretation, this article argues, first, that Kripke's Cicero/Feynman experiment reveals that every name user knows enough to be capable of identifying the same individual as the name's most informed users. Second, the article shows that Kripke's presentation of the Gödel/Jonah experiment is ambiguous with respect to the properties attributed to the referent. Disambiguated, the experiment fails to reveal that name users may be mistaken in every unique property they attribute. Since the experiment's ambiguity is replicated in survey presentations, cross‐cultural variation in survey response fails to show that intuitions about reference are culturally contingent.     

Adolescents’ Civic Commitments in Stable and Fledgling Democracies: The Role of Family,School, and Community

The authors examined the associations between adolescents’ perceptions of proximal processes in families, schools, and communities and their civic commitments (to the local community, nation, and conventional politics) in stable (Australia, United States) and fledgling (Bulgaria, Hungary) democracies in the mid-1990s. Results of multivariate analysis of covariance (MANCOVA) revealed that adolescents in the stable democracies reported higher levels of extracurricular participation, family emphasis on social responsibility, and community social capital compared to peers in the fledgling democracies. Using a multiple group regression approach, the authors found that in both types of polities, community social capital was positively associated with all three civic outcomes and a family ethic of social responsibility was positively associated with commitments to the local community and nation. However, whereas in the stable democracies, a democratic school climate was positively associated with commitments to the community and nation, in the fledgling democracies such school climates were positively associated with commitments to conventional politics.