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J T Cacioppo

Publications and source records attributed to J T Cacioppo.

At least 73 records · Page 4Linked to original sources
PubMed1990

Rudimentary physiological effects of mere observation.

Complex social factors can influence physiological activity, behavior, and health, but little is known about how essential components of these factors (e.g., human association, observation) affect human physiology. To begin to address this issue, an experiment was conducted to contrast predictions from social facilitation, distraction/conflict, and physiological reactivity formulations regarding the physiological effects of mere observation. Skin conductance and heart rate were measured surreptitiously from 27 women during a period in which they believe that the experimenter was simply calibrating auditory and physiological recording equipment. Approximately half of the subjects were led to believe that they could be observed by the experimenter during this period, and the remainder were led to believe that they could not be observed. Following baseline recordings, a series of 10 orienting tones were presented. Predictions from the physiological reactivity formulation were supported: (a) no differences in basal levels of somatovisceral activity were found as a function of mere observation; (b) mere observation enhanced the skin conductance response to the initial orienting tone; and (c) these physiological differences were punctate, quickly dissipating and quickly habituating. Hence, mere observation has subtler physiological effects than thought previously. Implications are discussed regarding the possible mechanism underlying the stress-enhancing and stress-buffering effects of human association, and regarding the effects social and contextual factors may have in psychophysiological research. Results from an international survey, based on the responses of 57 authors of articles that have appeared in Psychophysiology since 1983, are reported to inform the latter discussion. Results suggest that, even when social factors in psychophysiological research are minimized or held constant within studies, subtle differences in the social context across studies within and across laboratories may contribute to the appearance that psychophysiological relationships are unreliable.

Adolescent↗
PubMed1990

Issues in biometrics: offset potentials and the electrical stability of Ag/AgCl electrodes.

There has been a continuing interest in many areas of psychophysiological research in the quantification of slow wave bioelectric potentials recorded from the surface of the skin. However, surprisingly little research has focused specifically on methods for stabilizing and minimizing the offset potentials of the sintermetallic Ag/AgCl surface electrodes commonly used in such noninvasive bioelectric measurement. To provide empirically based recommendations in this regard, we contrasted the effects of three common storage methods (air dry vs. saline vs. carbon rod) on the two distinct types of Ag/AgCl surface electrodes (sintermetallic vs. electrolytic) under simulated experimental conditions. The obtained results confirm that minimum offset potentials and maximum stability for electrolytic Ag/AgCl electrodes are obtained when they are stored in a 0.9% NaCl solution with their leads shorted together and connected in parallel to a carbon rod partially immersed in the solution (cf. Cooper, 1956). In addition, the pattern of results suggested that the inter-session unshorted storage of sintermetallic electrodes in a mild saline solution is to be recommended over either shorted saline storage in parallel with a carbon rod or unshorted dry storage.

Electric Conductivity↗
PubMed1989

A psychometric study of surface electrode placements for facial electromyographic recording: I. The brow and cheek muscle regions.

Despite the burgeoning literature using facial electromyography (EMG) to study cognitive and emotional processes, the psychometric properties of facial EMG measurement have received little attention. Two experiments were conducted to assess the reliability and validity of facial EMG as a measure of specific facial actions. In Experiment 1, two recording sites in the brow region were compared for their ability to differentiate facial actions hypothesized to be due to the activation of the corrugator supercilii from facial actions presumed to be due to the activation of proximate muscles (e.g. depressor supercilii, procerus, frontalis, levator labii superioris alaeque nasi, orbicularis oculi), and four sites in the infraorbital triangle were compared for their ability to differentiate facial actions hypothesized to be due to the activation of the zygomaticus major from facial actions presumed to be due the activation of proximate muscles (e.g. zygomaticus minor, risorius, buccinator, orbicularis oculi, orbicularis oris). Fifteen subjects were instructed to pose a series of facial actions while EMG activity was sampled simultaneously at all sites. In Experiment 2, 5 subjects returned to the laboratory for a more extensive investigation of surface EMG activity over the zygomaticus major muscle region. The results of this experiment confirmed the findings of Experiment 1. Overall, the results demonstrate that certain recording sites located over specific facial muscle regions are more sensitive and valid indices of particular facial actions than other nearby sites.

Adult↗
PubMed1988

Specific forms of facial EMG response index emotions during an interview: from Darwin to the continuous flow hypothesis affect-laden information processing.

Previous research has demonstrated that mild negative emotional imagery and unpleasant sensory stimuli lead to greater electromyographic activity over the brow muscle region than mild positive imagery and stimuli, even in the absence of significant changes in visceral and general facial EMG activity. Previous research has not addressed whether electromyographic responses over the brow region are a sensitive and specific index of emotions, however, since a multiplicity of events lead to changes in brow activity. In this research, facial electromyographic and audiovisual recordings were obtained while individuals were interviewed about themselves. Afterwards, individuals were asked to describe what they had been thinking of during specific segments of the interview marked by distinctive electromyographic responses over the brow region in the context of ongoing but stable levels of activity elsewhere in the face. The results are interpreted in terms of a continuous flow hypothesis of affect-laden information processing.

Electromyography↗
PubMed1987

Self-report and cardiovascular measures of arousal: fractionation during residual arousal.

Residual arousal has been conceptualized as a state of physiological activation that is amenable to misattribution-like processes because individuals are unaware of their aroused physiological state (Zillmann, 1978). Although there is considerable evidence showing that people in the state labeled "residual arousal" rate excitatory stimuli in a more polarized fashion (see review by Zillmann, 1983), the available evidence for the notion that residual arousal is imperceptible can alternatively be interpreted as evidence of an inability to discriminate the cause of the residual arousal. To determine the nature of the cognitive representation of residual arousal (and, hence, whether excitation transfer is likely to be a nonconscious rather than conscious misattributional process), cardiac activity and reported arousal were tracked before, during, and following exercise. Results replicated previous research showing that exercise-induced cardiac activity remained significantly elevated when subjects ceased to report feeling aroused due to the exercise. These findings were extended through the joint use of magnitude estimation and psychophysiological procedures to index what level of exercise-induced bodily activation was reportable. Results indicated that residual arousal is unperceived rather than perceived and mistaken as to its cause. Implications of the present research range from theories of arousal and of misattribution to the effects of stress-related variations in cardiac performance on cardiac detection.

Adolescent↗
PubMed1986

Electromyographic activity over facial muscle regions can differentiate the valence and intensity of affective reactions.

Physiological measures have traditionally been viewed in social psychology as useful only in assessing general arousal and therefore as incapable of distinguishing between positive and negative affective states. This view is challenged in the present report. Sixteen subjects in a pilot study were exposed briefly to slides and tones that were mildly to moderately evocative of positive and negative affect. Facial electromyographic (EMG) activity differentiated both the valence and intensity of the affective reaction. Moreover, independent judges were unable to determine from viewing videotapes of the subjects' facial displays whether a positive or negative stimulus had been presented or whether a mildly or moderately intense stimulus had been presented. In the full experiment, 28 subjects briefly viewed slides of scenes that were mildly to moderately evocative of positive and negative affect. Again, EMG activity over the brow (corrugator supercilia), eye (orbicularis oculi), and cheek (zygomatic major) muscle regions differentiated the pleasantness and intensity of individuals' affective reactions to the visual stimuli even though visual inspection of the videotapes again indicated that expressions of emotion were not apparent. These results suggest that gradients of EMG activity over the muscles of facial expression can provide objective and continuous probes of affective processes that are too subtle or fleeting to evoke expressions observable under normal conditions of social interaction.

Adolescent↗
PubMed1984

Electromyographic specificity during simple physical and attitudinal tasks: location and topographical features of integrated EMG responses.

Integrated electromyographic (IEMG) activity was recorded using surface mini-electrodes placed over the corrugator supercilii, zygomatic major, levator labii superioris, masseter, obicularis oris and superficial forearm flexors muscle regions while subjects imagined or performed simple physical or attitudinal tasks. In the physical tasks, subjects either imagined they lifted or actually lifted a 16 gram or 35 gram weight. In the attitudinal tasks, subjects adopted either an agreeable or disagreeable attitudinal set as they silently read neutral text or imagined reading an editorial. Each task was performed for 12 sec on five separate occasions, and tasks were ordered randomly across the experimental trials. Following each trial, subjects provided self-reports regarding the extent to which the task was stressful, arousing and vivid. Multivariate analyses of the topographical features of each IEMG response were performed to determine the effects of the tasks on changes in IEMG response waveforms, and univariate analyses were conducted to assess the features of the waveform that were altered by tasks. Results support the efficacy of electromyographic studies of covert affective processing given that subjects are generally quiescent, unobtrusively observed, unaware that somatic activity is being recorded and involved in the task. The implications of these data for the somatic representation of affect are discussed.

Adolescent↗
PubMed1983

The relative impact of age and attractiveness stereotypes on persuasion.

The relative impact of the old-age and attractiveness stereotypes on persuasion was investigated. College students read essays that contained either cogent or specious arguments that were attributed either to young or old, socially attractive or unattractive authors. Evaluations of the essay itself were affected only by the quality of the arguments presented. Argument quality and attractiveness interacted to determine perceptions of the author and opinions on the position advocated in the essay: attractive authors were rated higher and were more persuasive than unattractive authors when the essay was strong, but were derogated and unpersuasive relative to unattractive authors when the essay was weak. Age of the author had an impact only on a few of the author-evaluation scales. A hierarchy of stereotype potency in which social attractiveness is prepotent over age is offered tentatively.

Adult↗
PubMed1982

Individual differences in relative hemispheric alpha abundance and cognitive responses to persuasive communications.

Three experiments are reported investigating individual differences in interhemispheric electroencephalogram (EEG) activity and cognitive responses to persuasion. Experiment 1 indicated that subjects who were characterized by relative left hemispheric EEG activity over the parietal areas also produced a less affectively polarized profile of thought listings about the persuasive communication. Moreover, this individual difference emerged only when subjects were confronted by the forewarning and message; the basal patterns of interhemispheric EEG activity, which were obtained prior to the announcement of the attitudinal recommendation, did not portend distinguishable profiles of cognitive responding. Experiment 2 replicated the major findings of Experiment 1 using different topics and a within-subjects rather than a between-subjects design. Further analyses suggested that thinking about an attitude issue rather than responding to a persuasive communication was sufficient to obtain the above relationship between interhemispheric EEG alpha abundance and cognitive response. Experiment 3 used Tesser's time-to-think procedure to assess interhemispheric EEG patterning as a function of the affective polarization of topic-relevant thinking. The results supported the expectation that as subjects thought longer about attitude issues they exhibited a shifting of relative hemispheric EEG activity from the left toward the right parietal areas of the cerebral hemispheres. The significance and limitations of these findings for research on attitude change and the utility of including psychophysiological approaches to elusive research problems in personality and social psychology are discussed.

Alpha Rhythm↗