Behavioral consequences of song learning: Discrimination of song types by male white-crowned sparrows

The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.     

Perceptions of candidate strength in job recruitment: Does candidate race moderate the attractiveness bias in White women?

The attractiveness bias suggests that people who are more attractive will be positively favored across life outcomes. This study sought to test whether candidate attractiveness, sex, and race, affect perceptions of candidate strength in a job recruitment task. In total, 338 White women (M_age = 20.94 ± 5.65) were asked to make judgements of a potential candidate for an administrative job (resume with candidate photograph). The vignettes differed in terms of candidate ability (strong/weak), sex (male/female), race (Black/White), and attractiveness (attractive/less attractive). Participants rated perceived candidate strength and likelihood to invite for interview. Results showed no significant main effects for attractiveness. However, there was a significant interaction for target attractiveness and race, such that attractive/White candidates were more likely to be invited for interview than less attractive/White candidates. There was also a significant main effect for race such that Black candidates were rated as stronger and more likely to be interviewed. Sensitivity analyses (with nonheterosexual women removed from the sample) also showed a main effect for target sex such that female candidates were favored over male candidates. Overall, these findings provide evidence that attractiveness, sex, and race have important, albeit complex, effects on hiring decisions in the workplace.     

A signal detection analysis of the effects of hearing on the visual recognition of two-digit numbers

A signal detection measure of visual recognition was used to assess the visual recognition of two-digit numbers in three different conditions: (1) voicing of the number as it was presented visually; (2) voicing of a different number than the one presented; and (3) no voicing. The three treatment means were significantly different, with matched voicing resulting in the best performance and no voicing, in the worst. There was no evidence that the treatments differentially affected response criteria.     

On the rate of stimulus occlusion during intermittent retinal stimulation

The CFF was determined with three sectored disks, each of which corresponded to one of the three rings in a Helmholtz disk. The fusion frequency is identical for all three rings of a Helmholtz disk but with the three sectored disks it was found that the rate of stimulus occlusion is a major factor in determining the CFF. It was tentatively concluded that the effect was not a consequence of different stimulus wave-forms. The phenomenon appears to have been reported late in the last century.     

Nonshared environmental influences and personality differences in adult twins

The twin design was used to examine the importance of different experiences of siblings within the family and to identify relations between twins' personality differences and their differential experiences. A sample of 161 monozygotic and 74 dizygotic twin individuals between the ages of 18 and 75 years retrospectively reported on their different experiences when growing up. The Sibling Inventory of Differential Experience (SIDE) was used for the first time with a sample of twin siblings. In addition, the twins provided self-report measures of affect and personality. In contrast to results from a sibling adoption design, this study of twins showed greater evidence for genetic variance in the SIDE scales. Nevertheless, the SIDE showed significant associations with differences in personality and affect for monozygotic twins, which reflect pure environment-behavior relations.     

Predicate-argument structure as a link between linguistic and nonlinguistic representations

We present a study wherein a severe Broca's aphasic patient was trained to learn symbols representing both pure transitive and dative predicates--predicates differing in argument structure--in a visually based artificial language (c-ViC). We found a decrease in performance when two symbols, rather than one, were used to depict these "verbs." However, this decrease in performance was more pronounced for symbols representing pure transitive verbs--those that allow only one argument structure--than for symbols representing dative verbs--those that allow two different argument structures. Also, dative "verbs" yielded better performance when they were inserted in more complex, three-argument "sentences" than when they were inserted in two-argument "sentences." The opposite pattern was found for pure transitives. These results are discussed in terms of our claim that argument structure serves as a point of connection between linguistic information and non-linguistic visual information and in terms of the possibility that argument structure entries are shaped by the form in which visual information is parsed.     

Determinants of Condom Use Among High-Risk Heterosexual Adults: A Test of the Theory of Reasoned Action1

The research presents tests of traditional and augmented versions of Fishbein and Ajzen's Theory of Reasoned Action (TRA), applied to condom use among adult clients of a sexually transmitted disease clinic. In a longitudinal survey, predictor variables suggested by Ajzen and Fishbein (1980), plus gender and condom use self-efficacy, were measured at Time 1. Condom use at Time 2, 3 months later, was regressed onto these variables. The traditional TRA worked well to predict condom use intentions and behavior. Support was also found for inclusion of gender and self-efficacy in the prediction of intention to use condoms, but not behavior. Implications for interventions to increase condom use among those at high risk for AIDS and other STDs are discussed.     

Parenting stress in parents of children with attention-deficit hyperactivity disorder and parents of children with learning disabilities

Parenting a child with ADHD can challenge parenting resources and coping. Increasingly, researchers are examining the relationship between the behavior of the child with ADHD and family functioning. While studies have shown inceased parenting stress in parents of children with ADHD, these studies have compared children with ADHD to non-disabled children. This study compares reports of parenting stress among mothers of children with ADHD, mothers of children with learning disabilities and mothers of non-referred children. Results showed that parenting stress was highest for mothers of children with ADHD. Increased parenting stress was associated with child characteristics and, in particular, with externalizing behavior problems.