Impulsive choice and altruistic punishment are correlated and increase in tandem with serotonin depletion

Human cooperation may partly depend on the presence of individuals willing to incur personal costs to punish noncooperators. The psychological factors that motivate such 'altruistic punishment' are not fully understood; some have argued that altruistic punishment is a deliberate act of norm enforcement that requires self-control, while others claim that it is an impulsive act driven primarily by emotion. In the current study, we addressed this question by examining the relationship between impulsive choice and altruistic punishment in the ultimatum game. As the neurotransmitter serotonin has been implicated in both impulsive choice and altruistic punishment, we investigated the effects of manipulating serotonin on both measures. Across individuals, impulsive choice and altruistic punishment were correlated and increased following serotonin depletion. These findings imply that altruistic punishment reflects the absence rather than the presence of self control, and suggest that impulsive choice and altruistic punishment share common neural mechanisms.     

Stimulus spacing effects in duration perception are larger for auditory stimuli: Data and a model

Models of duration bisection have focused on the effects of stimulus spacing and stimulus modality. However, interactions between stimulus spacing and stimulus modality have not been examined systematically. Two duration bisection experiments that address this issue are reported. Experiment 1 showed that stimulus spacing influenced the classification of auditory, but not visual, stimuli. Experiment 2 used a wider stimulus range, and showed stimulus spacing effects for both visual and auditory stimuli, although the effects were larger for auditory stimuli. A version of Temporal Range Frequency Theory was applied to the data, and was used to demonstrate that the qualitative pattern of results can be captured with the single assumption that the durations of visual stimuli are less discriminable from one another than are the durations of auditory stimuli.     

RAISING MALE PRIVILEGE AWARENESS AND REDUCING SEXISM: AN EVALUATION OF DIVERSITY COURSES

Research examining the impact of women's studies courses provides evidence of student changes such as greater agreement with feminist and egalitarian attitudes, lower prejudice against women, and increased activism. Using a pre- and posttest design, the current studies assess students' awareness of male privilege, prejudice against women, support for affirmative action, and identification as feminist following courses with and without gender content. In Study 1, students taking a course entitled Psychology of Race and Gender completed identical surveys during the first and last weeks of the semester. Study 2 included students in Psychology of Women, Introduction to Women's Studies, and courses not addressing gender. Participants in diversity and women's studies courses in both studies exhibited more male privilege awareness and support for affirmative action at the end of the semester compared to pretest. However, the change in women's studies students' support for affirmative action and sexism levels was not significantly different from students in comparison courses. Women's studies students completed their courses with greater self-identification with feminism in contrast to non–women's studies students.     

Resistance to Interference of Olfactory Perceptual Learning

The Psychological Record - Olfactory memory is especially persistent. The current study explored whether this applies to a form of perceptual learning, in which experience of an odor mixture...     

Predictors of online information seeking by international students when disaster strikes their countries.

This study explores factors influencing international students' likelihood of using the Internet to seek disaster-related information should a disaster affect their countries. A cross-sectional survey was conducted in two universities in America between August 1 and September 30, 2005. Two hundred twenty-nine (n = 229) students completed the self-administered questionnaires. ANOVA analyses found that respondents' Internet self-efficacy had no significant impact on their intentions to seek disaster-related information on the Internet. However, respondents' Internet dependency and attitude toward seeking information online were found to have a significant effect on such intentions.     

Difficulty in evoking odor images: The role of odor naming

Many studies report that people have difficulty in evoking odor images. In this article, we explore whether this results from another commonly observed phenomenon, difficulty in naming odors. In Experiment 1, participants both named and attempted to imagine either odors or their common visual referents. More-difficult-to-name odors were reported as being more difficult to evoke as olfactory images, in comparison with the visual condition. In Experiment 2, participants received training prior to forming odor images and naming the same set of odors. As in Experiment 1, more-difficult-to-name odors were harder to imagine, but participants who had learned the odor names during training were significantly better, by their own report, at imagining many of these stimuli, relative to participants who were either exposed to the odors, exposed to their names, or who received no pretraining. In sum, these experiments suggest that odor naming may account for some of the difficulty reported by participants when attempting to evoke odor images; we discuss an associative basis for this effect.     

The Ouchi illusion: An anomaly in the perception of rigid motion for limited spatial frequencies and angles

The spatial parameters underlying a novel illusion of relative motion are characterized. A simple stimulus composed of two sine-wave gratings was sufficient to generate the illusion. We measured the response of subjects to rapid, small-amplitude oscillations of this stimulus behind a fixation point. The effect was clearly strongest for acute angles between the gratings, but only when spatial frequency was between 6 and 11 cpd. We surmise that activity in the grating cells of the primate visual cortex (von der Heydt, Peterhans, & Dursteler, 1992) might be the cause of the illusion. The illusion is potentially an important tool in understanding how higher cortical areas combine disparate motion signals.