Are rats short-sighted? Effects of stimulus distance and size on visual detection

Behavioural evidence concerning short-sightedness in rats is apparently conflicting: in some experiments rats have performed poorly with visual stimuli further than about 60 cm distant, while in others they have made efficient use of more distant cues, for example to find their way through mazes. However, in the experiments suggesting short-sightedness, the physical size of the stimuli was not varied, so that stimulus distance and visual angle were confounded. In the present experiment, therefore, the size and distance of the stimuli to be detected were varied independently. Over the range tested (30-160 cm), distance was found to produce relatively slight effects on the smallest detectable visual angle, and these tended to diminish with practice. Thus, no good evidence was found for short-sightedness in rats up to 160 cm, a finding consistent with current views of the structure and image-forming capacities of the rat's eye. The smallest detectable targets were, however, surprisingly large in view of the rat's visual acuity (which is about 1c/deg): at the distances tested, animals required considerable training to run reliably to targets subtending less than 5-10° of visual angle. Difficulties in responding to stationary stimuli of this size are likely to restrict severely the use that rats make of vision both in the laboratory and in their natural surroundings.     

The impact of informant gender on children’s endorsement of scientific and non-scientific information

By roughly 6 years of age, children acquire the stereotype that men are more competent than women in science, technology, engineering, and mathematics (STEM), potentially leading to greater trust in scientific information provided by men. This study tested whether 3- to 8-year-old children differentially endorsed conflicting information about science and toys presented by male and female informants depicted as a ‘man’ and ‘woman’ (Exp1) or ‘scientists’ (Exp2). Children were expected to endorse toy testimony from gender-matched informants; thus, the key question concerned endorsement of science testimony. In Exp1 (N = 149), boys and girls showed a same-gender informant preference for toy testimony; however, girls endorsed the male informant's testimony more for science than for toys – but only when tested by a male experimenter. In Exp2 (N = 264), boys and girls showed a same-gender preference, irrespective of content. Findings suggest that STEM-related gender stereotypes might lead girls to trust scientific information presented by men over women in certain contexts.     

Terror Management and Personality: Variations in the Psychological Defense Against the Awareness of Mortality

Drawing on terror management theory (TMT), we discuss the psychological motivations that shape personality at two levels: the characteristically human personality common to us all and the individual differences that distinguish some people from others. TMT posits that the motivation to protect the self against deep-rooted fears about mortality drives people to maintain meaningful, reliable conceptions of reality and positive evaluations of themselves, two broad tendencies that form the foundation of every person’s personality. We review studies showing that mortality reminders increase efforts to bolster cultural sources of meaning and self-esteem in similar ways across individuals and cultures. TMT also posits that individual differences in personality partly reflect the different sources of meaning and self-esteem that people invest in to assuage mortality fears. We review evidence that individual differences predict the degree and direction of people’s defensive responses to mortality reminders. Directions for future research are discussed.     

Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity.     

Environmental Modesty

Despite this virtue's history as an instrument of women's oppression, modesty, at its most basic, means voluntary restraint of one's power, undertaken for the sake of others. It is a mechanism that modifies unequal power relationships and encourages greater compassion and fairness. I use a Christian perspective with influences from Jewish and Muslim sources to examine modesty. The modest person, I argue, must be in relationship with others, must be honestly aware of her impacts on others, must be sensitive to those impacts, compassionate toward others, and willing to hold back for others' sakes. Moreover, modesty is not only a virtue that pertains to sexuality and clothing, but it also can promote virtuous environmental behavior, particularly as it leads to awareness of, and sensitivity to, the effects of everyday behaviors on vulnerable others.     

Student Response to Three Types of Orientation Programs

A high proportion of positive responses was obtained from students who participated in three different types of pre-college orientation programs. Small group approaches consistently elicited more favorable responses than assemblies or large groups. Greater faculty involvement resulted in participants' noting an increased academic emphasis. Participants believed they had benefited in some way from programs which varied considerably as to length, activities, organization, and purposes.