Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity.     

International Applications of Computer-based Testing and Interpretation

The computer has been used to administer, score and interpret psychological tests in a number of countries throughout the world. This paper traces early work in the United States, Great Britain and continental Europe and reviews the current international status of computer-assisted psychological testing. Several problems with transporting existing computer-based psychological testing technology across languages and cultures are discussed.
Les ordinateurs sont utilisés pour administrer, noter et interpréter les tests psychologiques dans un certain nombre de pays du monde entier. Cet article évoque les travaux réalisés aux Etats-Unis, en Grande Bretagne et en Europe Occidentale, et passe en revue les données du courant international en la matière. Plusieurs problèmes technologiques sont soulevés par la diffusion de ces tests, notamment sur les plans du langage et de la culture.     

TEACHING SELF-PROTECTION TO CHILDREN USING TELEVISION TECHNIQUES

This study compared the effectiveness of a videotape training program with other methods of teaching children self-protection to prevent child abduction. Subjects were kindergarten and first-grade students. Four experimental conditions were presented: videotape with behavior rehearsal, videotape only, a standard safety program, and no training. Acquisition of self-protective behaviors was measured at posttraining and follow-up by having confederate adults entice the children near their schools and homes. Results revealed that the videotape program with behavior rehearsal was highly effective in teaching children safe responses to potential abductors. The standard safety program was effective with fewer than half of the children. Three fourths of the children who received no training immediately agreed to go with the confederate suspects. The videotape program can be easily used with groups of young children in a classroom setting.     

The probability of war in then-crises problem: Modeling new alternatives to Wright's solution

In hisStudy of War, Q. Wright considered a model for the probability of warP during a period ofn crises, and proposed the equationP=1–(1–p) ⁿ , wherep is the probability of war escalating at each individual crisis. This probability measure was formally derived recently by Cioffi-Revilla (1987), using the general theory of political reliability and an interpretation of the n-crises problem as a branching process. Two new, alternate solutions are presented here, one using D. Bernoulli's St. Petersburg Paradox as an analogue, the other based on the logic of conditional probabilities. Analysis shows that, while Wright's solution is robust with regard to the general overall behavior ofp andn, some significant qualitative and quantitative differences emerge from the alternative solutions. In particular,P converges to 1 only in a special case (Wright's) and not generally.C.C.-R. acknowledges support provided by the Merriam Laboratory for Analytic Political Research, the Research Board of the University of Illinois, and grant SES-84-00877 from the U.S. National Science Foundation.     

Does spreading activation summate?

Summary Network models of semantic memory assume implicitly or explicitly that the degree of activation of a node is a monotonic function of the total amount of excitation reaching that node from all sources. For example, the activation level of the node representing apple should be greater if it is receiving excitation due to the activation of the nodes for fruit and pear than if only one of these neighboring nodes is activated. This notion was tested by presenting semantic primes 80 ms or 320 ms before a letter string (e.g., apple or ipple) requiring a lexical decision. The prime stimuli consisted of a pair of simultaneous items that were identical in the single prime condition (e.g., fruit/fruit or pear/pear) or different in the double prime condition (e.g., fruit/pear or pear/fruit), and were either related (target = apple) or unrelated (target = copper) to the target, or neutral. As predicted by the summation of semantic activation assumption of network models there was a larger priming effect (in the 320 ms SOA condition) following the simultaneous activation of two related nodes than following the activation of only one node.This research was supported by grants to the first author from the Natural Sciences and Engineering Research Council of Canada.     

Temporary suppression of visual processing in an RSVP task: an attentional blink? .

Through rapid serial visual presentation (RSVP), we asked Ss to identify a partially specified letter (target) and then to detect the presence or absence of a fully specified letter (probe). Whereas targets are accurately identified, probes are poorly detected when they are presented during a 270-ms interval beginning 180 ms after the target. Probes presented immediately after the target or later in the RSVP stream are accurately detected. This temporary reduction in probe detection was not found in conditions in which a brief blank interval followed the target or Ss were not required to identify the target. The data suggest that the presentation of stimuli after the target but before target-identification processes are complete produces interference at a letter-recognition stage. This interference may cause the temporary suppression of visual attention mechanisms observed in the present study.     

Family reunions: Visionary encounters with the departed in a modern-day psychomanteum

A poignant feature of many near-death experiences is a visionary encounter with deceased loved ones. Over the centuries, researchers have sought safe ways to replicate near-death and related experiences, hoping to induce the powerful aftereffects of these events. The ancient Greeks contructed psychomanteums, or oracles of the dead, where seekers could consult spirits of the deceased. I describe a modern attempt to recreate the psychomanteum. Like near-death experiences, visionary encounters in this modern psychomanteum are experienced as real and not as hallucinatory, and have profound personal aftereffects. This novel experimental technique may permit the scientific study of phenomena that previously occurred only spontaneously and under uncontrolled circumstances.