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.     

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.     

The Systematic Measurement of French and Raven's Bases of Social Power in Workgroups

A typology of five bases of social power developed by French and Raven (1959) has been used to study small-group behavior in field settings by various researchers but interpretation of these data is limited by several methodological shortcomings. This study describes the development and testing of questionnaire measures for the Legitimate, Expert, Referent, Reward, and Coercive bases of social power and attempts to correct some of the scale format confounds that have affected previous empirical efforts. Analyses of Likert-scaled responses from the 23-item questionnaire show for the first time that these five constructs are factorially identifiable and orthogonal. Scale responses are shown to accurately reflect hierarchical status differences in an organization and to correlate significantly with such common leader behaviors as Initiation of Structure and Consideration.     

Dimensions of affective experience in three age groups.

The dimensions by which adults of differing ages experience emotion were studied by self-administering questionnaires administered to older adults (n = 828) recruited from Elderhostel programs, middle-aged (ages 30-59) children of Elderhostel attenders (n = 231), and young adult (ages 18-29) subjects recruited from college classes or through Elderhostel participants (n = 207). Elders were higher in emotional control, mood stability, and emotional maturity through moderation and leveling of positive affect and lower in surgency, psychophysiological responsiveness, and sensation seeking. These findings are consistent with the hypothesized increase in self-regulatory capacity with age. These cross-sectional differences cannot, however, be distinguished from cohort-related explanations; they require considerable replication across different types of subjects and further characterization of the dimensions in terms of their functions for self-regulation.     

A Test of Bipolar and Androgyny Perspectives of Masculinity and Femininity: The Effect of Participation in an Outward Bound Program

ABSTRACT The purposes of the present investigation are to examine theoretical issues in androgyny theory by testing the effect of participation in the Outward Bound program on measures of masculinity (M) and femininity (F) Bipolar conceptualizations of MF posit that an increase in either M or F must lead to a decrease in the other, whereas androgyny theory posits M and F to be independent constructs Consistent with a priori predictions based on the nature of the Outward Bound program, participation substantially enhanced M and had a small positive effect on F The results were reasonably consistent for male and female participants, for single-sex and mixed-sex groups, and across responses to three different MF measures Results support the androgyny interpretation of MF and demonstrate the effectiveness of the Outward Bound program in changing MF The results contradict the bipolar perspective that an increase in M must be accompanied by a decrease in F     

The Attitudes Toward Women Scale for Adolescents (AWSA): A study of reliability and validity

This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely supported. AWSA permits the examination of how boys' and girls' attitudes toward women influence the life paths that adolescent girls begin to pursue.This research was supported by grants to A. Petersen from the Spencer Foundation, the National Institute of Mental health (MH 30252/38142), and the Judith Baskin Offer Fund.     

Alcoholism: A conflict of models

Adherents to the traditional model of alcoholism explain alcoholic behavior as a consequence of alcoholism. Alcoholism is identified as an unseen, unmeasured entity inherent in alcoholics. This concept parallels the thinking of Copernicus, Kepler, Galileo, and Newton, who believed in an unseen, unmeasurable creator behind the physical world. These traditional approaches contrast with the emergent model of alcoholism and twentieth-century scientific thought. Emergent scientific model adherents explain alcoholic behavior without resort to unseen factors. Since the traditional and emergent scientific models begin with different assumptions, model adherents experience communication difficulties. Future developments with determine which model will dominate the field of alcohol studies and treatment.