Selective Synaptic Plasticity within the Cerebellar Cortex Following Complex Motor Skill Learning

Complex motor skill learning, but not mere motor activity, leads to an increase in synapse number within the cerebellar cortex. The present experiment used quantitative electron microscopy to determine which synapse types were altered in number. Adult female rats were allocated to either an acrobatic condition (AC), a voluntary exercise condition (VX), or an inactive condition (IC). AC animals were trained to traverse an elevated obstacle course requiring substantial motor coordination to complete. VX animals were housed with unlimited access to running wheels and IC animals received no motor training but were handled briefly each day. Results showed the AC animals to have significantly more parallel fiber to Purkinje cell synapses than both the VX and IC animals. No other synapse type was significantly altered. Thus, the learning-dependent increase in synapse number observed within the cerebellar cortex is accomplished primarily through the addition of parallel fiber synapses.     

Edward Bordin: Fusing Work and Play

This article contains highlights of an interview with Edward Bordin, who later died on August 24, 1992, after a long battle with prostate cancer. It focuses both on his professional history and contributions to the field as well as on his personal life. We were honored to learn from his wife Ruth that portions of the material that follows were read at his funeral service.     

The Inter-Domain Model of Career Assessment and Counseling

In this article the author presents a summary of the Inter-Domain Model applied to career assessment and counseling (Lowman, 1991), which formally encompasses three major categories of variables: occupational interests, abilities, and personality characteristics. The requirements of a theory of career assessment are reviewed and the major components of the Inter-Domain model discussed.     

Achievement and Power Motives, Performance Feedback, and Creativity

Undergraduate students in engineering and science completed the Thematic Apperception Test, which was scored for achievement motivation and also for power motivation. They later participated in an experiment in which they first provided a solution to an engineering problem. The experimenter then gave them preprogrammed, written feedback on how well they performed in two conditions of the experiment (positive or negative feedback) and no feedback in a third condition. Feedback was couched in the language of both achievement and power imagery. Last, students rendered solutions to a second engineering problem—the water-for-Tonya problem. Two students who had completed a course in the psychology of creativity performed ratings of each solution on dimensions designated as creativity and complexity. Ratings for the two dimensions moderately correlated with one another (r = .62) and therefore were combined and summed across the two evaluators to form a single overall Creativity score. Achievement motivation correlated positively with Creativity score in the positive- and negative-feedback conditions (rs = .43 and .38) but not significantly in the no-feedback condition (r = .10). Power motivation correlated positively with Creativity in the positive-feedback condition (r = .32), and negatively in the negative-feedback condition (r = −.25), but not significantly in the no-feedback condition (r = .17). Multiple regression/correlation analysis lent further support to these findings. A major conclusion that these data suggest is a differential response to negative feedback. Achievement-motivated people appear to benefit from it, whereas power-motivated people do not.     

Efficacy of two behavioral treatment programs for comorbid geriatric insomnia

Older adults with comorbid insomnia and medical illness have been excluded from behavioral treatment research, but recent evidence suggested that such treatments would be effective with this population. In this study, 38 older adults with comorbid insomnia were randomized to 1 of 3 conditions: classroom cognitive-behavioral treatment (CBT), home-based audio relaxation treatment (HART), or delayed-treatment control. Compared to the control group, the CBT group had significant changes in 5 of 7 self-report measures of sleep at the 4-month follow-up. The HART group obtained significant outcomes on 3 of 7 measures. Wrist actigraphy measures and secondary-outcome measures did not yield significant findings for either treatment. Clinically significant changes at follow-up were obtained for 54% of patients in CBT, 35% in HART, and 6% in the control group when treatment dropouts were included. Although not as effective as in-person CBT, home interventions may have utility as a first-line, low-cost treatment.     

A role for olfaction in object recognition by normal and hippocampal-damaged rats

To examine how olfactory and visual factors affect object discriminations in rats with and without hippocampus damage, the authors trained Long-Evans rats on simple object discriminations. They then examined how these discriminations were affected by rotations of the objects, by coating the objects in a transparent acrylic coating, or by both rotating and coating the objects in acrylic. The rats displayed no impairments when the objects were only sprayed in acrylic, and they displayed minor impairments when the objects were rotated. However, when the objects were both rotated and acrylic coated, the rats displayed severe impairments. This suggests that the rats are solving the rotated-only phase based on surface features of the objects (probably odor) and not based on the visual information. Such species' biases for obtaining object information are important factors to consider when designing and interpreting visual memory experiments across species. There was no difference in performance between the rats with hippocampus damage and the sham rats, and this is consistent with the literature on similar tasks.