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J J Furedy

Publications and source records attributed to J J Furedy.

At least 55 records · Page 3Linked to original sources

Intuitive and factual approaches in the comparison of contractility and repolarization measures of sympathetic myocardial activity.

Obrist (Cardiovascular Psychophysiology: A Perspective, Plenum Press, New York, 1981) has recently argued for the superiority of contractility (e.g. pulse transit time) over ventricular repolarization (e.g. T-wave amplitude) measures as indices of sympathetic myocardial influences on the grounds that the T-wave occurs during the diastolic portion of the cardiac cycle (in contrast to the systolic temporal locus of contractile-based measures). This note suggests that this argument is intuitively rather than factually based because it lacks both logical and empirical validity.

Electrocardiography↗

Evoked potential correlates of intelligence: some problems with Hendrickson's string measure of evoked potential complexity and error theory of intelligence.

The string measure of evoked potential (EP) complexity is based on a new error theory of intelligence, which differs from the older speed-based formulations which focus on EP latency rather than complexity. In this note we first raise a methodological problem of arbitrariness with respect to one version of the string measure. We then provide a comparative empirical assessment of EP-IQ correlations with respect to a revised string measure (which does not suffer from the methodological problem), a latency measure, and another measure of EP complexity: average voltage. This assessment indicates that the string measure, in particular, yields quite disorderly results, and that, in general, the results favor the speed over the error formulation.

Evoked Potentials↗

The relative sensitivities of heart rate and T-wave amplitude to stress: comments on, and some alternative interpretations of, Penzien et al.'s results.

Although the joint measurement of heart rate (HR) and T-wave amplitude (TWA) in experiments manipulating psychological processes is a sound and fruitful approach, Penzien Hursey, Kotses and Beazel's (1982) interpretation of their results may be questioned on two grounds: (a) Wether the process being manipulated between their groups was really the degree of stress; and (b) whether the degree of threat or aversiveness is really indexed more reliably by HR changes than by changes in TWA. This note questions these two assumptions, and also offers an alternative vagal interpretation of the Penzien et al. (1982) results.

Adaptation, Psychological↗

The double-alternative, double-start experimental apparatus: A new procedure for measuring preference.

A new experimental chamber is described that permits rats to demonstrate behavioral preference for one of two conditions by running towards a goal chamber by one of two routes that are correlated with the different conditions. In a preliminary study, rats chose a route correlated with relatively lower shock, demonstrating the sensitivity of the apparatus. We also report evidence using this device that, of 10 rats tested, all preferred unsignaled rather than signaled, inescapable, unavoidable shock.

Journal Article↗

Operational, analogical and genuine definitions of psychophysiology.

The reason for considering definitional issues is not that of arriving at a universally agreed-to definition, but rather that of illuminating scientific disagreements. From this viewpoint it will be argued that operational and analogical definitions which have been offered by psychophysiology are not useful, because they do not permit the settling of disputes on objective grounds. Those grounds are relevant only for genuine definitions, which can be tested in terms of the counter-example argument in general, and in particular in terms of whether they adequately differentiate psychophysiology from the closely related but different area of physiological psychology. One such genuine but inadequate definition is that offered by Stern (1964), which differentiates the two areas in terms of the dependent and independent variables being, respectively, manipulated and measured. The definition offered here is in terms of the interests of the investigator, and is that psychophysiology is the study of psychological processes in the intact organism as a whole by means of unobtrusively measured physiological processes. I shall argue that this definition more adequately differentiates psychophysiology from physiological psychology than does Stern's definition. In addition, I shall suggest that adopting this definition does not isolate the two areas from one another, but rather brings them into a more scientifically meaningful relationship. Finally, I shall illustrate, with some examples, how (implicitly adopted) definitions that are different from the proposed one here lead to substantive differences in both the conduct and evaluation of research in psychophysiology. Definitional issues, in other words, are not only of relevance for ivory-tower, armchair philosphers. They affect not only the practice of empirical basic research, but also applied practice.

Autonomic Nervous System↗

Anticipatory HR deceleration as a function of perceived control and probability of aversive loud noise: a deployment of attention account.

Five groups of 10 undergraduate subjects each participated in an experiment to examine the effects of perceived control over, and the probability of occurrence of, noxious (white-noise) stimulation on anticipatory heart rate (HR) deceleration. All groups performed an arithmetic task, the numbers for which were changed on each of the 20 trials, but three groups were defined as active groups since they were instructed that the occurrence of noxious stimulation was contingent upon their performance on the task. The actual probability of occurrence of noxious stimulation (i.e., either 0.9, 0.5 or 0.1) was manipulated between these three groups. A fourth (passive) group (0.5 probability of occurrence) was instructed as to the non-contingent relationship between performance and the aversive white noise. The last group was a control group which only performed the task, and thus both provided an estimate of the rate of return to baseline following the expected HR acceleration to the task and eliminated the need for a within-subject control period to assess HR deceleration. The results indicated that all active and passive groups produced significant HR decelerations, relative to the control group, prior to the noxious stimulus. However, all active groups (regardless of probability levels) displayed significantly greater, and required more trials to maximally develop, anticipatory deceleration than the passive group. In addition, the results for the active groups revealed a direct relationship between the probability of occurrence of noxious stimulation and the magnitude of anticipatory deceleration. It is argued that the results cannot be adequately accommodated by the preparatory-adaptive-response theory. A deployment-of-attention account is suggested since it appears both to account for the obtained pattern of results completely and to generate additional testable predictions for the future.

Adaptation, Psychological↗