Discounting in causality and covariation judgements

In two experiments, humans were asked to judge the strength of a moderate contingency between a cue and an outcome in the presence of a second strong contingency between another cue and the outcome. The first experiment replicated the discounting effect whereby a strong contingency causes subjects to reduce or discount judgements of a moderate contingency. This experiment used a video-game procedure in which subjects camouflaged a tank to make it safe from mines. The second causal cue was the presence or absence of a spotter plane. Experiment 1 also ruled out the possibility that judgements might be determined by the number of co-occurrences of the cue and outcome as opposed to the level of contingency. The second experiment used an abstract scenario in which discounting was demonstrated when subjects were asked to judge the relationship between the occurrence of geometric objects. The instructions were neutral to discourage causal hypotheses. These results support the notion that judgements result from associative or connectionist processes and not from a two-step cognitive retrospective process in which an estimate of covariation is calculated between cue and outcome and then in a second step this information is used in a normative manner when a decision is made.     

Stress,Coping, and Suicide Risk in Psychiatric Inpatients

The present study investigated the relationship between interpersonal problems, coping styles, and suicide risk. Seventy-one adult psychiatric inpatients completed a suicide risk scale, a measure of interpersonal problems, and a coping scale designed to measure eight coping styles. Patients admitted with a history of suicidal attempts were compared with patients admitted for other reasons. Interpersonal problems were found to be significantly and positively related to suicide risk. The coping style of “suppression” (tendency to avoid threatening or uncomfortable situations) was found to be significantly and positively related to suicide risk [F(2, 68) = 4.54, p < .01]. Several other coping styles were found to be significantly related to suicide risk. These findings are congruent with a “two-stage model of countervailing forces” and have both research and clinical implications.     

Helm and Boltzmann: Energetics at the Lübeck Naturforscherversammlung

The energetics controversy is understood variously as energy vs. atoms, thermodynamics vs. statistical mechanics, phenomenalism vs. realism, equations vs. pictures, and especially Ostwald vs. Boltzmann. It is generally thought that at Lübeck in 1895 Boltzmann and Planck demolished energetics, but while its momentum was slowed, energetics in one or more of the above senses still retained supporters as late as the great physics conference at the St. Louis World’s Fair in 1904. Indeed, after Ostwald himself abandoned it in 1908, Ernst Mach began for the first time to defend it. The main emphasis in this paper, however, is on Georg Helm (1851–1923) who had been invited to Lübeck to be the main speaker on energetics. He had adopted his position earlier than Ostwald and his views avoided many of the errors and oversights in Ostwald’s approach. Indeed, Helm could be called the strongest defender of energetics, even if Ostwald was Boltzmann’s main target. Helm was largely Machist in philosophy at that time and did not reify energy. This revised version was published online in June 2006 with corrections to the Cover Date.     

On the status of implicit memory bias in anxiety

The present study evaluated the status of mood congruent memory bias in implicit memory tasks for threat related information. A literature review complemented by three experiments on high and low trait anxiety participants found no implicit memory bias for threat-related information in anxious individuals on either word fragment completion or tachistoscopic word identification tasks. The theoretical implications of these results are discussed.