Interaction of cognitive and sensorimotor maps of visual space

Studies of saccadic suppression and induced motion have suggested separate representations of visual space for perception and visually guided behavior. Because these methods required stimulus motion, subjects might have confounded motion and position. We separated cognitive and sensorimotor maps without motion of target, background, or eye, with an “induced Roelofs effect”: a target inside an off-center frame appears biased opposite the direction of the frame. A frame displayed to the left of a subject’s center line, for example, will make a target inside the frame appear farther to the right than its actual position. The effect always influences perception, but in half of our subjects it did not influence pointing. Cognitive and sensorimotor maps interacted when the motor response was delayed; all subjects now showed a Roelofs effect for pointing, suggesting that the motor system was being fed from the biased cognitive map. A second experiment showed similar results when subjects made an open-ended cognitive response instead of a five-alternative forced choice. Experiment 3 showed that the results were not due to shifts in subjects’ perception of the felt straight-ahead position. In Experiment 4, subjects pointed to the target and judged its location on the same trial. Both measures showed a Roelofs effect, indicating that each trial was treated as a single event and that the cognitive representation was accessed to localize this event in both response modes.     

The Unintended Negative Consequences of Sympathy for the Stigmatized1

Research on attitudes toward the stigmatized indicates that negative feelings and stereotypes toward the stigmatized are often mixed with positive feelings of sympathy and concern. Three studies investigate the hypothesis that positive outcomes for the stigmatized that are motivated by sympathy may have unintended negative consequences for self-esteem, affect, and motivation. Subjects were asked to imagine themselves in the position of a stigmatized person who received a job either because he or she was qualified, or out of sympathy for a stigmatizing condition. Results indicated that subjects reported lower state self-esteem, more negative affect, and lowered work motivation when the job was offered out of sympathy rather than on the basis of qualifications. Study 2 showed that the negative effects of sympathy occur whether the basis for the sympathy is prejudice and discrimination or mobility problems faced by the stigmatized individual. The third experiment showed that sympathy has negative effects when the sympathy is based either on individual or group-based problems imposed by the stigmatizing condition. The findings are discussed in terms of the attributional ambiguity surrounding positive outcomes faced by the stigmatized and applied to the effects of affirmative-action programs.     

Assessing the stability of principal components using regression

This paper presents an analysis, based on simulation, of the stability of principal components. Stability is measured by the expectation of the absolute inner product of the sample principal component with the corresponding population component. A multiple regression model to predict stability is devised, calibrated, and tested using simulated Normal data. Results show that the model can provide useful predictions of individual principal component stability when working with correlation matrices. Further, the predictive validity of the model is tested against data simulated from three non-Normal distributions. The model predicted very well even when the data departed from normality, thus giving robustness to the proposed measure. Used in conjunction with other existing rules this measure will help the user in determining interpretability of principal components.The authors would like to thank the four anonymous reviewers and the two editors for their valuable comments. Atanu R. Sinha gratefully acknowledges the research support received from the Marketing Studies Center, AGSM, UCLA. Send requests for reprints to Atanu R. Sinha, B418 Gold Hall, 110 Westwood Plaza, Los Angeles, CA 90095.     

Reply to Chrzan’s comments

1 This paper discusses the following works: Alvin Plantinga,The Nature of Necessity, Oxford University Press 1974, Chapter 9 Section 11; Keith Chrzan, ‘Plantinga on Atheistic Induction,’Sophia Vol 27 No. 2 (July 1988), 10–14; Bruce Langtry, ‘God, Evil and Probability,’,Sophia Vol 28 No. 1 (April 1989), 32–40; and Keith Chrzan, ‘Comment on Langtry's “God, Evil and Probability”,’Sophia Vol 32 No. 2 (July 1993), 54–58. The numbering of propositions throughout is the same as in my earlier paper. All page references to Chrzan are to his second paper.     

Public knowledge,attitudes, and beliefs about homeless people: Evidence for compassion fatigue?

Media reports suggest that the public is becoming impatient with the homeless—that so-called “compassion fatigue” has gripped the nation. This characterization of public sentiment could have important policy consequences—restrictive measures can be justified by growing public impatience, and progressive housing policies seem infeasible within a hostile climate of opinion. But evidence to support the compassion fatigue notion is anecdotal. We examine the issue by tracking the results of public opinion polls and by reporting detailed evidence from a nationwide random-digit dial telephone survey (N=1,507) concerning knowledge attitudes and beliefs about homeless people. To be sure, the public sees homelessness as an undesirable social problem and wants something done about it. However, although the homeless are clearly stigmatized, there is little evidence to suggest that the public has lost compassion and is unwilling to support policies to help homeless people.     

A behavioral link between the oculomotor and cardiovascular systems

Although the eyes and the heart serve very different purposes, each receives autonomic innervation. Capitalizing on recent theoretical and technological innovations in the understanding and assessment of oculomotor and cardiovascular behavior, three experiments measured behavioral covariation between the oculomotor and cardiovascular systems. Measures of dark focus and dark vergence indexed oculomotor tone, and the spectral decomposition of variations in heart rate indexed cardiovascular control mechanisms. In Experiment 1, individual differences in cardiovascular parameters could predict individuals’ dark vergence (R²=.806) but not their dark focus (R²=.404). In Experiment 2, the same parameters were measured from subjects who experience either panic attacks (n=11) or blood phobia (n=9). Heart rate was positively correlated with dark vergence and the two subject groups were separable based on both oculomotor and cardiovascular variables. Using a within-subjects approach, Experiment 3 found that both dark vergence and dark focus tended to be nearer during sympathetic dominance of the heart than during parasympathetic dominance, within-subjects variations in cardiovascular parameters could predict dark focus, and between-subjects variations in interbeat intervals could predict dark vergence. Shared patterns of autonomic activation may be responsible for this eye-heart link.