Modality specificity of implicit memory for new associations

In previous research we demonstrated that newly acquired associations between unrelated word pairs influence the magnitude of priming effects on word-completion tests. This phenomenon of implicit memory for new associations is observed only following semantic study elaboration. The present experiments reveal that implicit memory for new associations, though elaboration dependent, is also modality specific: Associative effects on a visual word-completion test were consistently reduced by study-test modality shifts. In contrast, explicit memory for new associations, as indexed by cued-recall performance, was uninfluenced by modality shifts. The modality effect on completion performance was eliminated when subjects were given brief visual preexposures to, or were required to construct visual images of, word pairs presented in auditory study conditions. The results pose a theoretical puzzle insofar as they indicate that within the domain of implicit memory, access to the products of elaborative processing depends on modality-specific, sensory-perceptual processing.     

Frontal lobe dysfunction and memory impairment in patients with chronic progressive multiple sclerosis

Deficits in semantic encoding have been described in patients with frontal lobe disease who also show memory impairments. As a group, patients with multiple sclerosis (MS) exhibit memory impairment, fail to make effective use of semantic encoding to aid memory, and perform poorly on verbal fluency and concept formation tests which are sensitive to frontal lobe damage. In the present study the semantic encoding capacity of MS patients was measured using a modification of Wicken's release from proactive interference (PI) paradigm. Individual patients varied considerably in the severity of their impairments on verbal fluency, verbal recognition memory and on Wisconsin Card Sorting Task, but even patients who evidenced both memory impairment and signs of frontal lobe dysfunction showed normal release from PI after a categorical shift. Memory disturbances in MS are unlikely to result from an incapacity for semantic encoding, which seems preserved in MS, but may arise instead from deficits in processing information rapidly.     

Forecasting the impact of the federal sentencing guidelines

The Sentencing Reform Act of 1984, which created the U.S. Sentencing Commission, required that the commisson consider prison capacity in drafting sentencing guidelines. As part of the commission's efforts to meet this requirement, we developed a computer simulation capable of projecting the impact of the commission's guidelines on future sentences and prison populations. According to our projections, “straight” probation sentences will be reduced significantly under the guidelines. However, reducing the use of probation will generate only modest demands on the prisons, and then mostly for community corrections phased in over the course of 5 years. We also project that, while average time served for violent offenses will increase substantially, average time served for most property crimes will remain largely the same. Finally, while we forecast that federal prison populations will grow markedly by the end of this century, this is more a result of the Anti-Drug Abuse Act of 1986 and the career offender provision of the Comprehensive Crime Control Act of 1984 than a result of the guidelines.     

Hugs or shrugs: Parental and peer influence on continuity of involvement in sport by female adolescents

The study was designed to examine the influence of significant others (mothers, fathers, and male and female peers) on continuing involvement in sport by adolescent females. Survey data were collected from 376 girls using a forced-choice, self-administered questionnaire. Maintenance of involvement was measured by the proportion of possible years in which the respondents were involved in physical activity within each of three participation contexts (intramural, interschool, and community sport). Several indicators of significant other influence were used. The degree to which involvement in physical activity is maintained is positively related to the source, amount and type of influence received from significant others, and varied by the participation context. Overall, the socializing influence of significant others was able to account for 11% of the variance in intramural activity, 20% of the variance in interschool sport, and 10% of the variance in community-based activity.This study was funded by a grant from Fitness Canada.     

Errors in the quantification of uncertainty: A product of heuristics or minimal probability knowledge base?

The use of intuitive heuristics (e. g. representativeness and availability) has been put forward as an explanation for peoples' assignment of probabilities (Tversky and Kahneman, 1971). This phenomenon is seen as robust since experts as defined by education (professional psychologisis), despite advanced training in statistics and methodology, rely on the same heuristics as novices (lay people). Both experts and novices, as defined by education, were studied in a series of experiments and further classified as experts and novices according to their probability knowledge base, prior to receiving (or not) a brief (15-minute) training session. Immediately following training, subjects completed a probability test which consisted of ten Tversky and Kahneman (e. g. 1974) problems. The training significantly increased the number of problems correctly solved on the probability test and eliminated the expert/novice education classification. The results of a follow-up test 5 weeks after the experiment indicated that the training group maintained its superior performance. It is proposed that failure to use proper methods of probability assignment may not be due to intrinsic human inference biases or heuristics, but is a result of a minimal probability knowledge base.     

TIMEX2: A modified C-language timer for PC AT class machines

Emerson (1988) provided a simple C-language timing routine for use with PC AT class machines. Unfortunately, this version of the timing routine makes use of nonstandard functions that are not available in all C-language packages. A modified version of this timing routine that does not make use of one of these nonstandard functions is provided. This version of TIMEX runs under the widely available Microsoft C 5.1. The need and availability of the remaining four nonstandard C functions is discussed. Constants needed to convert the timing routine units into seconds and milliseconds are also provided.     

Statistical analysis of fuzzy-set data from neuronal networks

In this study, we describe the process of transforming neuron polarization values that meet the assumptions of ratio data into ordinal data. This is a crisp-to-fuzzy set transformation. A computerized simulation of the application of this process is discussed and nonparametric methods of analyzing fuzzy-set data are presented.