Object recognition contributions to figure-ground organization: Operations on outlines and subjective contours

In previous research, replicated here, we found that some object recognition processes influence figure-ground organization. We have proposed that these object recognition processes operate on edges (or contours)detected early in visual processing, rather than on regions. Consistent with this proposal, influences from object recognition on figure-ground organization were previously observed in both pictures and stereograms depicting regions of different luminance, but not in randomdot stereograms, where edges arise late in processing (Peterson & Gibson, 1993). In the present experiments, we examined whether or not two other types of contours—outlines and subjective contours—enable object recognition influences on figure-ground organization. For both types of contours we observed a pattern of effects similar to that originally obtained with luminance edges. The results of these experiments are valuable for distinguishing between alternative views of the mechanisms mediating object recognition influences on figure-ground organization. In addition, in both Experiments 1 and 2, fixated regions were seen as figure longer than nonfixated regions, suggesting that fixation location must be included among the variables relevant to figure-ground organization.     

Measuring and predicting the effects of alcohol consumption on contrast sensitivity for stationary and moving gratings

Contrast sensitivity was measured for 12 healthy young males while sober, after ingestion of an alcohol placebo, and after ingestion of alcohol (95% grain alcohol; mean estimated blood alcohol level = .088%). Observations were made for both stationary gratings and gratings that traveled through a circular path and required pursuit eye movements. The significant alcohol-related reduction in contrast sensitivity was 2.6 times greater for moving (.29-log-unit reduction) than for stationary gratings (.11-log-unit reduction). The loss in contrast sensitivity for the moving gratings of high spatial frequency (12 cpd) was particularly severe (.37 log unit). Estimated blood alcohol level was correlated with the loss in contrast sensitivity for moving gratings (r = .61), but not with the loss for stationary gratings. Estimated blood alcohol level was strongly correlated with the difference between the loss in contrast sensitivity to moving and stationary gratings (r = .75). These results are consistent with reports that alcohol consumption degrades the ability to make pursuit eye movements. Subjects’ perceived intoxication level was not a reliable predictor of any index of visual performance.     

Children's Decisions About Substance Use: An Application and Extension of the Theory of Reasoned Action1

This research examines the applicability of Fishbein and Ajzen's (1975) theory of reasoned action (TRA) to intentions to use cigarettes and alcohol among 5th- and 6th-grade students. It also addresses the question of unidimensionality of outcome beliefs and referent norms. Results suggest that the TRA model describes children's decision making well, although the ability of income and race to add to prediction, net of the effects of attitude and perceived norm, are contrary to the theory's prediction. In addition, we find support for multidimensional components of both attitude and norm for both behaviors.     

USING REINFORCEMENT-BASED METHODS TO ENHANCE MEMBERSHIP RECRUITMENT IN A VOLUNTEER ORGANIZATION

The present study employed reinforcement-based methods to induce existing members to recruit new members to join a chamber of commerce. Three interventions took place during June and July of 3 successive years. The investigators trained chamber leaders to use reinforcement methods (e.g., contingent tokens) to reinforce recruitment and dues collections. All three interventions produced substantial increases in their targets.     

Helping Unrelated Strangers: Physical and Psychological Reactions to the Bone Marrow Donation Process Among Anonymous Donors1

The development of models that predict outcomes of voluntary action is important for practitioners who manage large groups of volunteers. In accordance with this goal, a path model was generated linking predonation characteristics of volunteer marrow donors to postdonation physical and psychological reactions. Questionnaire data were collected from 343 individuals registered to donate marrow to unrelated strangers at 3 time points: shortly predonation, shortly postdonation, and 1-year post- donation. Although donors had generally positive reactions to donation, a substantial minority reported ambivalence about donating, physical difficulty with donation, and negative psychological reactions postdonation. In addition, our data suggest that predonation ambivalence is a central predictor of postdonation reactions, even after other donor characteristics are taken into account. These results have practical implications for the recruitment of volunteers, and suggest important variables to be considered in evaluating potential bone marrow donors.     

The Impact of Sex and Gender Role Self-Perception on Affective Reactions to Different Types of Film

To what extent do differences in biologicalsexand psychological gender identity influence affectivereactions to different genres of film? In order toaddress this question, this investigation examined the impact of sex and gender roleself-perceptions on viewers' responses to neutral,melodramatic, and violent film segments. Working with apredominantly Caucasian population (93% Caucasian) at asoutheastern university, the results emphasize theimportance of sex and gender role self-perceptions onviewers' affective responses to media entertainment. Theimplications of these findings are discussed.

     

Empirically defined symptom scales using the DISC 2.3

Empirically defined scales of depressive, attention deficit hyperactivity disorder, oppositional-defiant disorder, and conduct symptoms from the lay-administered National Institute of Mental Health (NIMH) Diagnostic Interview Schedule for Children (DISC), version 2.3, and evidence of their reliability and validity, are presented. The scales were developed using factor analyses of data obtained from an epidemiologic survey of over 1,200 children drawn from four sites across the U.S. and Puerto Rico (the NIMH Methods for the Epidemiology of Child and Adolescent Mental Disorders, or MECA Study). Their psychometric properties were tested in a subsample of children reinterviewed by clinicians. The findings support the use of these continuous measures. The scales are strongly related to the diagnostic categories and show good test-retest reliability. The scales can be used to characterize severity in children with diagnoses and to describe problems and symptoms in children without diagnoses. Because these scales can measure gradations in symptomatology, they may be more useful than categorical measures. Like categorical measures, the scales based on the DISC are greatly influenced by the informant, whether child or parent.This research was supported by grant MH-46732 from the National Institute of Mental Health, Bethesda, Maryland.The MECA Program is an epidemiologic methodology study performed by four independent research teams in collaboration with staff of the Division of Clinical Research, which was reorganized in 1992 with components now in the Division of Epidemiology and Services Research and the Division of Clinical and Treatment Research, of the NIMH, Rockville, Maryland. The NIMH Principal Collaborators are Darrel A. Regier, MD, MPH, Ben Z. Locke, MSPH, Peter S. Jensen, MD, William E. Narrow, MD, MPH, and Donald S. Rae, MA; the NIMH Project Officer was William J. Huber. The Principal Investigators and Coinvestigators from the four sites are as follows: Emory University, Atlanta, Georgia, UO1 MH46725: Mina K. Dulcan, MD, Benjamin B. Lahey, PhD, Donna J. Brogan, PhD, Sherryl Goodman, PhD, and Elaine Flagg, PhD; Research Foundation for Mental Hygiene at New York State Psychiatric Institute (Columbia University), New York, New York, UO1 MH46718: Hector R. Bird, MD, David Shaffer, MD, Myrna Weissman, PhD, Patricia Cohen, PhD, Denise Kandel, PhD, Christina Hoven, PhD, Mark Davies, MPH, Madelyn S. Gould, PhD, and Agnes Whitaker, MD; Yale University, New Haven, Connecticut, UO1MH46717: Mary Schwab-Stone, MD, Philip J. Leaf, PhD, Sarah Horwitz, PhD, and Judith H. Lichtman, MPH; University of Puerto Rico, San Juan, Puerto Rico, UO1 MH46732: Glorisa Canino, PhD, Maritza Rubio-Stipec, MA, Milagros Bravo, PhD, Margarita Alegría, PhD, Julio Ribera, PhD, Sarah Huertas, MD, and Michael Woodbury, MD.The authors gratefully acknowledge Zenaida González and José Martínez who performed the data nalayses, as well as Elizabeth Pastrana, and Felícita Laboy, secretaries, for their valuable contributions to this work.