Sufficient conditions for the discrimination of motion

When one half of a randomly contoured pattern is displaced in one of four directions between successive exposures, Ss are capable of discriminating the direction of the displacement. Accuracy of discriminating decreases as a function of the relative displacement within the pattern, independent of the visual angle subtended by the pattern. Supplementary data suggest that Ss are unrealistically confident in the accuracy of their discrimination. The results demonstrate that identification of specific contours is not necessary for the discrimination of motion and suggest that some type of correlational process is employed by the visual system in dealing with spatially and temporally displaced patterns.     

Echolocation in the blinded rat

The difference threshold for detection of barriers at different distances using a modified method of limits was found, for four blinded rats, to be 9 in. White noise 20 dB above ambient level reduced discrimination performance to chance, indicating that auditory cues were involved in the discrimination. A second determination, utilizing the method of constant stimuli, confirmed the difference threshold to be 9 in. and reduced individual S variation by further training. Evidence with a black and a white barrier indicated the possibility that infrared heat cues do not enter into the discrimination.     

SEXIST DISCRIMINATION MAY ACCOUNT FOR WELL-KNOWN GENDER DIFFERENCES IN PSYCHIATRIC SYMPTOMS

It was hypothesized that women may have more depressive, anxious, and somatic symptoms than men because they experience a deleterious stressor that men do not: sexist treatment. A total of 255 students (180 females, 75 males) at a state university completed an anonymous questionnaire containing measures of these symptoms. Women were found to exhibit significantly greater symptoms than men on all of them. Further, women who experienced frequent sexism had significantly more symptoms than men on all symptom measures, whereas women who experienced little sexism did not differ from men on any symptom measure. These findings suggest that gender-specific stressors not only play a role in psychiatric symptoms among women but may account for well-known gender differences in those symptoms as well.     

An evaluation of multi‐criteria methods in integrated assessment of climate policy

Those who conduct integrated assessments (IAs) are aware of the need to explicitly consider multiple criteria and uncertainties when evaluating policies for preventing global warming. MCDM methods are potentially useful for understanding tradeoffs and evaluating risks associated with climate policy alternatives. A difficulty facing potential MCDM users is the wide range of different techniques that have been proposed, each with distinct advantages. Methods differ in terms of validity, ease of use, and appropriateness to the problem. Alternative methods also can yield strikingly different rankings of alternatives. A workshop was held in which climate change experts and policy makers evaluated the usefulness of MCDM for IA. Participants applied several methods in the context of a hypothetical greenhouse gas policy decision. Methods compared include value and utility functions, goal programming, ELECTRE, fuzzy sets, stochastic dominance, min max regret, and several weight selection methods. Ranges, rather than point estimates, were provided for some questions to incorporate imprecision regarding weights. Additionally, several visualization methods for both deterministic and uncertain cases were used and evaluated. Analysis of method results and participant feedback through questionnaires and discussion provide the basis for conclusions regarding the use of MCDM methods for climate change policy and IA analyses. Hypotheses are examined concerning predictive and convergent validity of methods, existence of splitting bias among experts, perceived ability of methods to aid decision‐making, and whether expressing imprecision can change ranking results. Because participants gained from viewing a problem from several perspectives and results from different methods often significantly differed, it appears worthwhile to apply several MCDM methods to increase user confidence and insight. The participants themselves recommended such multimethod approaches for policymaking. Yet they preferred the freedom of unaided decision‐making most of all, challenging the MCDM community to create transparent methods that permit maximum user control. Copyright © 2002 John Wiley & Sons, Ltd.     

Neural correlates of intertemporal choice in aggressive behavior

People often have to make decisions between immediate rewards and more long-term goals. Such intertemporal judgments are often investigated in the context of monetary choice or drug use, yet not in regard to aggressive behavior. We combined a novel intertemporal aggression paradigm with functional neuroimaging to examine the role of temporal delay in aggressive behavior and the neural correlates thereof. Sixty-one participants (aged 18–22 years; 37 females) exhibited substantial variability in the extent to which they selected immediate acts of lesser aggression versus delayed acts of greater aggression against a same-sex opponent. Choosing delayed-yet-more-severe aggression was increased by provocation and associated with greater self-control. Preferences for delayed aggression were associated with greater activity in the ventromedial prefrontal cortex (VMPFC) during such choices, and reduced functional connectivity between the VMPFC and brain regions implicated in motor impulsivity. Preferences for immediate aggression were associated with reduced functional connectivity between the VMPFC and the frontoparietal control network. Dispositionally aggressive participants exhibited reduced VMPFC activity, which partially explained and suppressed their preferences for delayed aggression. Blunted VMPFC activity may thus be a neural mechanism that promotes reactive aggression towards provocateurs among dispositionally aggressive individuals. These findings demonstrate the utility of an intertemporal framework for investigating aggression and provide further evidence for the similar underlying neurobiology between aggression and other rewarding behaviors.     

Violence Exposure and Sexual Risk Behaviors for African American Adolescent Girls: The Protective Role of Natural Mentorship and Organizational Religious Involvement

African American adolescent girls are at increased risk of being exposed to community violence and being diagnosed with a sexually transmitted infection. Fewer studies, however, have examined the protective roles of natural mentorship and organizational religious involvement as potential moderators that could lessen the effects of violence exposure on health risk behavior. Data from 273 African American ninth grade girls were used to test hypothesized independent and moderated‐moderation models. Results suggest that natural mentorship and religious involvement were protective for girls who reported at least one mentor and moderate to high levels of religious involvement. Our findings may be relevant for community stakeholders and organizations that directly interact with religious institutions and community programs that focus on outreach to African American adolescent girls.     

The promotion of self-forgiveness,responsibility, and willingness to make reparations through a workbook intervention

This study evaluated the effectiveness of a workbook intervention designed to promote self-forgiveness, acceptance of responsibility, and willingness to make amends/reparations in a university student sample. The intervention manual consisted of three parts: (a) promoting prosocial and responsible attitudes, (b) reducing barriers to self-forgiveness, and (c) promoting healthy thinking and behaviors. Outcome measures included acceptance of responsibility, motivation to make reparations, and state and trait self-forgiveness. Measures were administered pre-intervention and immediately post-intervention. Participants were randomly assigned to an intervention group (N = 50) or a control group (N = 43). The control group studied materials for their university courses instead of completing the intervention. Following the intervention, the intervention group had significantly a higher state and dispositional self-forgiveness post-test compared to the control group. Changes in acceptance of responsibility and willingness to make reparations did not reach statistical significance as compared to the control group.