ALL: Automated learning laboratory

ALL is a CAI package designed to give students “hands-on” experience with a primitive learning laboratory. Using ALL, students can serve as either research subjects or experimenters. Both schedules of reinforcement and the nature of the reinforcer may be varied within the program for a number of simple learning tasks.     

Effect of preconditioning unconditioned stimulus experience on learned taste aversions.

One taste-aversion study using male Long-Evans rats in which ethanol was the unconditioned stimulus (UCS) and six studies in which lithium chloride (LiCl) was the UCS demonstrate that (a) exposure to the UCS prior to conditioning retards subsequent acquisition of learned taste aversions; (b) a single preconditioning UCS exposure is sufficient to attenuate conditioning; (c) the preconditioning UCS exposure must occur within a limited period prior to conditioning to attenuate learning; (d) repeated conditioning trials will override the effect of prior exposure to the UCS; (e) tolerance to the UCS is not a necessary condition for the attenuation effect to occur; (f) pairing the preconditioning UCS with a novel flavor other than the CS does not remove the preexposure effect, although it may reduce its magnitude; and (g) the degree of disruption is a positive function of preconditioning UCS dosage and an inverse function of conditioning UCS dosage.     

Young children's processing of asymmetrical and symmetrical patterns

Dot patterns varying in type of symmetry (double symmetry, vertical symmetry, horizontal symmetry, and asymmetry) were presented tachistoscopically for 200 msec, followed by a patterned mask, to kindergarten, second-grade, and fourthgrade children. All subjects reported symmetrical patterns more accurately than asymmetrical patterns. Double symmetry patterns were reproduced more accurately than vertical symmetry patterns, and vertical symmetry patterns were reproduced more accurately than horizontal symmetry patterns. These results stand in marked contrast to previous research by demonstrating that the ability to process symmetrical relationships evolves early in perceptual development. There was a suggestion that subjects of all ages perceived information about the type of symmetry presented in the display, but there were agerelated differences in subjects' abilities to use this knowledge in constructing their responses. Additionally, analyses revealed no age-related biases toward imposing symmetrical responses on asymmetrical patterns.     

Successful Postgraduate Placement Experiences: What is the Influence of Job and Supervisor Characteristics?

We know little about what determines an effective placement experience, yet vocational placements are an integral part of many professional degree programmes. The aim of this research was to examine the influence of job (task variety, task identity, task significance, feedback, and autonomy) and supervisor (relationship quality and mentoring) characteristics on placement outcomes. The findings were tested on samples from two professions for which placement were a compulsory part of their course. Sample 1 consisted of 266 undergraduate nurses, and sample 2 consisted of 176 postgraduate psychologists. The findings showed that job and supervisor characteristics explained unique variance in professional development and placement satisfaction. Of the five job characteristics examined, skill variety, feedback from the job, and task significance influenced placement outcomes. Mentoring emerged as the most important supervisor characteristic that was associated with professional development and placement satisfaction, and to a slightly less extent, supervisor–student relationship quality was also important. The research and practical implications of the findings were discussed.     

Psychological and social-structural influences on commitment to volunteering

A model is described in which commitment to volunteering is hypothesized to be the result of demographic qualities, personality, identity, values, and social relationships. The model is tested and cross-validated using data from a nationally representative sample of American adults. The results from structural equation modeling analyses suggest that the hypothetical model provides a good fit to the data. Moreover, the findings suggest that the relations of personality and demographic characteristics to hours devoted to volunteering are largely mediated by latent constructs capturing helping identity and community participation. The implications of the model and the findings for our understanding of volunteering are discussed.