How do memory systems interact? Evidence from human classification learning

Studies of human classification learning using functional neuroimaging have suggested that basal ganglia and medial temporal lobe memory systems may interact during learning. We review these results and outline a set of possible mechanisms for such interactions. Effective connectivity analyses suggest that interaction between basal ganglia and medial temporal lobe are mediated by prefrontal cortex rather than by direct connectivity between regions. A review of possible neurobiological mechanisms suggests that interactions may be driven by neuromodulatory systems in addition to mediation by interaction of inputs to prefrontal cortical neurons. These results suggest that memory system interactions may reflect multiple mechanisms that combine to optimize behavior based on experience.     

Task characteristics and performance in interpersonal cognitive problem solving

The authors examined the extent to which performance on interpersonal cognitive problem-solving (ICPS) tasks is affected by whether the goals within the dilemmas to be addressed are sex typed. Fifty children, aged 7-8 years old, were tested for the core ICPS skills of Alternative Solutions Thinking (AST) and Consequential Thinking (CT) on a series of 8 social problem-solving tasks, 4 having goals characteristically more attractive to boys and 4 with goals more attractive to girls. A 2 x 2 MANOVA was used to compare the performances of boys and girls on each set of sex-typed tasks with the 3 dependent variables of liking for the tasks, number of alternative solutions suggested, and the number of consequences anticipated. As expected, liking for the tasks was higher if the activities were characteristically associated with the participant's own gender (p < .001), although the different tasks did not produce any significant gender differences in the numbers of AST or CT suggestions they prompted. Gender differences in children's peer relationships were considered, and the implications of these results for the format of ICPS interventions are noted.     

Observing and engaging in purposeful actions with objects influences estimates of their size

A ladle was recalled as being taller by participants who observed tedious removal of sand from it with a small teaspoon than by those who observed removal with a larger spoon. A second experiment showed that the number of darts thrown in order to hit a target correlated negatively with memory estimates of the size of the target, a finding replicated in a third experiment with size estimates made while the target was visible. The first two experiments suggest that the way an object is used can influence memory of its size. The third experiment supports the hypothesis that in vivo size estimation of familiar objects may employ a mechanism that derives size from memory and that size memory can be distorted by the way an object was used.     

Put your money where your mouth is! Explaining collective action tendencies through group-based anger and group efficacy

Insights from appraisal theories of emotion are used to integrate elements of theories on collective action. Three experiments with disadvantaged groups systematically manipulated procedural fairness (Study 1), emotional social support (Study 2), and instrumental social support (Study 3) to examine their effects on collective action tendencies through group-based anger and group efficacy. Results of structural equation modeling showed that procedural fairness and emotional social support affected the group-based anger pathway (reflecting emotion-focused coping), whereas instrumental social support affected the group efficacy pathway (reflecting problem-focused coping), constituting 2 distinct pathways to collective action tendencies. Analyses of the means suggest that collective action tendencies become stronger the more fellow group members "put their money where their mouth is." The authors discuss how their dual pathway model integrates and extends elements of current approaches to collective action.     

Attitude formation through exploration: valence asymmetries

The formation of attitudes toward novel objects was examined as a function of exploratory behavior. An initial experiment, in which participants played a computer game that required them to learn which stimuli, when sampled, produced favorable or unfavorable outcomes, demonstrated learning, attitude formation, and generalization to novel objects. The findings also revealed 2 interesting valence asymmetries: a learning asymmetry involving better learning for negatively valenced than positively valenced objects and a generalization asymmetry involving stronger generalization as a function of negative than of positive attitudes. Findings from 4 experiments led to an explanation of the learning asymmetry in terms of information gain being contingent on approach behavior and related the generalization asymmetry to a negativity bias that weighs resemblance to a known negative more heavily than resemblance to a positive.     

VIZ: The visualization assessment and training Web site

The VIZ Website(http:/viz.bd.psu.ech]/viz/) was developed as a free and open portal for assessment and training of spatial skills. Using Macromedia Authorware, it allows the collection of response times and accuracies from four spatial tasks: mental rotation, paper folding, water level judgments, and spatial working memory. Additional tasks are under development. The site has been used for a variety of teaching and research purposes. For example, incoming engineering students have completed the tasks to assess their spatial skills before beginning their graphics courses. Those with poorer skills can then receive the appropriate remedial instruction. The VIZ site has also been used to teach about spatial cognition and to do research outside the laboratory setting. Finally, we are using the site to conduct basic research on spatial cognition, including an examination of the factors that may reduce gender differences in performance.     

An MMPI-2 scale to identify reported history of emotional abuse

A 42-item MMPI-2 scale classified 97.5% of 201 clinic outpatients into groups reporting or not reporting prior emotional abuse.     

Task-effector asymmetries in a rhythmic continuation task

Variability in rhythmic movements has been interpreted as a signature of internal or peripheral noise processes. Grounded in an oscillator interpretation, this study hypothesized that period variability and drift arises from the asymmetry between target period and the limb's intrinsic dynamics. Participants synchronized to 7 target periods, swinging 1 of 3 pendulums in a continuation paradigm; 3 periods were longer, 3 shorter, and 1 identical to the preferred period. Results supported 5 predictions: Drift toward the preferred period was observed that scaled with the asymmetry. Variability was lowest for symmetry conditions and increased with the asymmetry. Variability decreased concomitant with the approach toward the preferred period. Periods exponentially approached the preferred period with positive autocorrelations up to 10 cycles.     

Equivalence relations in individuals with language limitations and mental retardation

The study of equivalence relations exhibited by individuals with mental retardation and language limitations holds the promise of providing information of both theoretical and practical significance. We reviewed the equivalence literature with this population, defined in terms of subjects having moderate, severe, or profound mental retardation. The literature includes 55 such individuals, most of whom showed positive outcomes on equivalence tests. The results to date suggest that naming skills are not necessary for positive equivalence test outcomes. Thus far, however, relatively few subjects with minimal language have been studied. Moreover, we suggest that the scientific contributions of studies in this area would be enhanced with better documentation of language skills and other subject characteristics. With recent advances in laboratory procedures for establishing the baseline performances necessary for equivalence tests, this research area is poised for rapid growth.