Electrodermal System Research Articles

Psychophysiological Reactions to Persuasive Messages Deploying Persuasion Principles

Measurement of physiological reactions to persuasive messages can improve our understanding of psychological processes of persuasion, and potentially further enhance and personalize current persuasion interventions. However, little is known about the relationship between psychophysiology and persuasive processes. This study focused on four persuasion principles: scarcity, commitment, consensus, and authority, and people's susceptibility to them. Physiological measures included the cardiovascular, respiratory, and electrodermal system, as well as facial motor systems. Psychological measures consisted of self-reported attitude towards oral care and susceptibility to persuasion (STPS). We performed a randomized within-subject experiment in which fifty-six participants viewed persuasive messages deploying the aforementioned persuasion principles to improve their oral care. Results indicated different physiological patterns during persuasion versus rest. We found no different physiological patterns in exposure to distinct persuasion principles, nor a clear correlation with susceptibility to individual persuasion principles. However, mixed model analysis illustrated that overall STPS scores help explain variance in reactivity of skin conductance level and skin conductance response, and reactivity in the zygomaticus major: lower susceptibility relates to higher reactivity. Summarizing, we have found no conclusive support for distinct psychophysiological patterns associated with different persuasion principles, although overall susceptibility seems to be reflected in physiology to some extent.

Does the Electrodermal System "Take Sides" When It Comes to Emotions?

Traditionally, electrodermal research measurements were taken from the non-dominant hand. This was considered a valid measurement of arousal for the whole body. Some, however argue for a complex and asynchronous electrodermal system in terms of lateral and dermatome differences in emotional responding. The present study measured skin conductance responses to emotionally laden musical stimuli from the left and right index and middle fingers, as well as the left and right plantar surface of right handed participants (N = 39). The 7-s musical segments conveyed four emotional categories: fear, sadness, happiness and peacefulness. Our results suggest, that the electrodermal system responds to emotional musical stimuli in a lateralized manner on the palmar surfaces. Fear, sadness and peacefulness prompted right hand dominance while happiness elicited left hand dominant response. Lateralization of the palmar and plantar surfaces differed significantly. Moreover, an association between lateralization of the electrodermal system in response to fear and state anxiety was found. Results of the present study suggest that the electrodermal system displays lateral preferences, reacting with varying degree of intensity to different emotions. Apart from lateral differences, music induced emotions show dermatome differences as well. These findings fit well with Multiple Arousal Theory, and prompt for revaluating the notion of uniform electrodermal arousal.

Design and characterization of a real-time, wearable, endosomatic electrodermal system

This paper presents the design and characterization of a compact wearable system for long-term assessment of skin potential response, with the aim of monitoring mental stress in a variety of applications. Literature reports that the expected skin potential has peak-to-peak amplitudes of few millivolts in the frequency band [0.1, 10]Hz. The designed system is characterized by a slightly wider bandwidth of [0.08, 40]Hz, and it is based on a 12-bit ADC working with a sampling rate of 200Sa/s, which can be increased up to 3.5kSa/s. Data can be continuously acquired for up to 40h with a battery of 3.7V/1800mAh. A Graphical User Interface was also developed for the host computer in .NET framework. The system, to our knowledge the first example of wearable endosomatic electrodermal activity sensor, joins to several skin conductance wearable measuring systems recently proposed in literature, and opens up opportunities for future comparisons of endosomatic and exosomatic responses in real life.The device is thoroughly characterized in accordance with the state-of-the-art of the metrological research in the field.

Reduced electrodermal response to errors predicts poor sustained attention performance in attention deficit hyperactivity disorder

Research into attention deficit hyperactivity disorder (ADHD) has indicated abnormalities in electrodermal system activity (EDA) and separately, deficits in sustained attention. Here we asked whether reduced EDA in ADHD was consequential for the attention problems associated with this disorder. On a sustained attention task ADHD participants had higher overall error rates and exhibited a marked decrease in skin conductance responses (SCRs) to errors, relative to control children. Further, sustained attention errors were predicted by SCR amplitudes. Evidence of post-error slowing in both groups suggested comparable error awareness. It is proposed that attenuation of the normal autonomic response to errors reflects impairment in ADHD participants' psychological response to error significance and results in decreased behavioural correction and hence poorer sustained attention.

Electrodermal Activity and Affective Symptoms in Allergic Depressed Inpatients

Electrodermal hypoactivity is a known phenomenon in depression. For different reasons a hyperactive electrodermal system should be more likely in allergic persons because of the known hyperreactivity both to psychological and immunological stimuli. Hypothesis of this study therefore was that this higher activity should also be seen in comorbid allergic depressed and anxious patients in comparison to non-allergic depressive patients. In a two-factorial variance analytic design (factor 1: anxiety/depression and anxiety/depression versus factor 2: allergy/non-allergy) we examined 45 age matched female depressed (D) and comorbid anxious (DA) inpatients of the Weissenau Depression Ward and female patients with anxiety/panic disorders (A) in a Budapest outpatient clinic. Besides measurement of electrodermal parameters (SCL, SFL, amplitude) patients filled in questionnaires (BDI, STAIG, B-L and a questionnaire regarding allergy). Results show no interaction between allergy and depression, but the three diagnostically groups differentiate as would be expected in BDI (p = 0.0038) with highest scores in DA; in all groups depression scores are highest in allergic patients (p = 0.07). Additionally in all diagnostic groups allergic patients had significantly higher electrodermal activity (SCL, p = 0.005) than non-allergic patients. Significant highest electrodermal activity were measured in the depressed group (D, p = 0.026) and not as we would have expected in the comorbid group DA. The implications for diagnostic-therapeutic strategies are discussed.

Bilateral electrodermal activity: relationships to state and trait characteristics of hemisphere asymmetry

Influences of trait and state characteristics of individual brain lateralization on bilateral electrodermal activity (EDA) were examined. EDA was observed in two different recording conditions: (1) non-specific skin conductance responses (ns.SCRs) were obtained during a stimulus-free recording period of 5 min; and (2) stimulus evoked skin conductance responses (SCRs) were elicited by 80 dichotically presented pairs of pure tones which — at the same time — constituted the items of a test to estimate subject's lateral ear dominance. In addition to ear dominance, degree of right-handedness and hemispheric preference, i. e. preferred direction of conjugate lateral eye movements (CLEMs) were assessed as trait-like characteristics of individual laterality. With respect to asymmetry of ns.SCRs, no effects of the laterality variables were observed. Analysis of SCRs, however, resulted in significant interactions of ear dominance and hemispheric preference with degree of right-handedness indicating higher SCR amplitudes on the hand contralateral to the preferred hemisphere in strong dextrals. Weak right-handers showed a different pattern of bilateral asymmetries, partly in the opposite direction. Additionally, phasic effects of cortical asymmetry on SCRs seem to be modified by trait characteristics of individual laterality. Results underline the importance of precisely controlling degree of handedness in studies of bilateral electrodermal activity. Furthermore, the observed effects support the assumption of cortical influences on EDA, but argue against the existence of a single cortical mechanism modulating asymmetries in the electrodermal system.

Personality, motivation and affect as modulating factors in suicidal behavior of depressed women

From a psychological point of view, we would expect that motivational rather than biological dysfunctions mediate initiation of violent and non-violent suicidal actions. To prove this assumption we classified depressed women in four groups according to their suicidal behaviour and matched them to age: suicide ideators, violent suicide attempters, non-violent suicide attempters, non-suicidal depressed controls. We then tested group differences in respect of aggression, impulsivity, introversion, affective lability, anxiety, depression and electrodermal activity (EDA). To take a closer look at motivational dysfunctions, we implemented the Action Control Scale (corresponding to Kuhls theory of action and state orientation), since we regard chronic state orientation as a risk factor for suicidal behaviour. Results show few differences in violent attempters compared with controls. In contrast to non-violent attempters, they show a greater tendency to achievement and action oriented behaviour being less introverted. Non-violent attempters, however, show most significant differences to their controls: Corresponding to a high state orientation, they are more depressed, anxious, less stable in respect of affectiveness, and more introverted, with low scores in aggression and contentedness in life. In contrast to some other studies, nonreactivity in the electrodermal system dominates in all groups. Results demonstrate that motivational dysfunctions like state orientation allow better prediction and understanding of violent or non-violent suicidal behaviour in depressed women than does electrodermal reactivity.

Individual differences in the orienting response: Nonresponding in nonclinical samples

The complete failure of the electrodermal orienting response (OR), although widely studied in clinical samples, has received little systematic attention in work with healthy adults. The published studies of nonresponding using nonclinical samples are reviewed, with data from three unpublished studies pertinent to the question, to identify the characteristics of nonresponders. The most durable findings to date are that nonresponding shows both trait and state characteristics, and that nonresponders are more likely to be female than male, to show hypoarousal in the electrodermal system but not complete unresponsiveness in this system or low arousal in other systems, and to show higher scores on measures of impulsiveness and antisociality but not to differ from responders in terms of sensation seeking. Most of these data can be reconciled with two different accounts of the OR mechanism. One is that proposed by I. Maltzman which postulates a difference between voluntary and involuntary ORs, and the other is that of J. A. Gray which proposes that the OR is a function of activity in a Behavioural Inhibition System. Taken together, these accounts imply that the OR reflects attentional and affective processes, and that both cognitive style and temperamental differences in the appraisal of threat can lead to electrodermal nonresponding.

Reflex modification in the electrodermal system: Conceptual and methodological issues

Reflex modification (RM) is the inhibition or facilitation of a reflex response by a stimulus (S1) occurring prior to a reflex-eliciting stimulus (S2). The present experiment investigated two issues: (1) whether RM may be confounded by orienting generated by changes in the experimental procedure, or habituation generated by repeated stimulus presentations; (2) whether the strength of RM is influenced by repeated pairings of S1 and S2, that is, classical conditioning. Two groups of subjects were given two series of stimulus presentations. Group A received first 10 S2-alone presentations, before 10 S1-S2 presentations. Group B received the stimuli in reversed order, that is, first 10 S1-S2 presentations, and then 10 S2-alone presentations. This design permits a comparison of unconfounded with confounded RM, as well as assessment of influences of learning. The results showed RM to be influenced by orienting caused by changes in the experimental procedure. The strength of RM tended to be gradually reduced as a function of the number of S1-S2 pairings, indicating that the orienting response to S1 habituated across trials. It is concluded that RM may be useful in the objective investigation of more complex cognitive processes.

Individual differences in psychophysiological responsiveness in laboratory tests of deception

The study examined the interrelationship of a number of measures of electrodermal activity under varying degrees of task demand and their relationship to differential electrodermal responding to critical questions in either a card test ( n=126) or a mock agent test ( n=84) of deception. The data indicated two dimensions of electrodermal responsiveness: one, a reactivity dimension, related predominantly to differences in base level, and the other, a lability dimension, related to differences in response frequency. A third dimension reflecting differences in the extent to which the electrodermal system was the most responsive relative to other systems was not independent of the second. Both the reactivity and lability dimensions related to indices of differential responding in the laboratory tests of deception, with the second increasing the predictive power of the first. The results were interpreted in terms of two-factor theories of the orienting response relevant to the physiological detection of deception.

Reciprocal hemispheric influences on response habituation in the electrodermal system

In three investigations, the rate of habituation of phasic electrodermal responses to auditory stimuli and the number of nonspecific responses were correlated with lateral differences in response amplitude. Fast habituation and less frequent responses were associated with higher left- than right-hand response amplitudes, whereas slow habituation and more frequent responding were associated with higher response amplitudes on the right hand. The results indicated a coincidence between the degree of phasic electrodermal activity and reciprocal hemispheric influences, implying hemispheric interactions in mechanisms that control phasic reactivity, habituation, and attention.

Orienting, habituation, sensitisation, and dishabituation in the electrodermal system of consecutive, drug free, admissions for schizophrenia

Thirty-three consecutive admissions for schizophrenia with PSE diagnoses and free of neuroleptics were compared with 31 hospital staff for distinguishing features of bilateral electrodermal activity to a sequence of mild tones followed by a sequence of conspicuous tones with variation of temporal parameters. To mild tones most patients were either non-responders or non-habituators whereas most controls were habituators or non-habituators. To conspicuous tones patients as a group were more responsive but without the features of sensitisation to a test stimulus shown by controls. Patients as a group had more non-specific responses and higher levels of skin conductance which showed less adaptation than controls. To a large extent previously reported difference in response latencies, rise-times and half-recovery times would appear to be a function of habituation rate. Patient-control differences may reflect anxiety and stress in patients, though lateral asymmetries in activity have a deeper salience for the nature of schizophrenia.

Reciprocal hemispheric influences on response habituation in the electrodermal system

In three investigations, the rate of habituation of phasic electrodermal responses to auditory stimuli and the number of nonspecific responses were correlated with lateral differences in response amplitude. Fast habituation and less frequent responses were associated with higher left- than right-hand response amplitudes, whereas slow habituation and more frequent responding were associated with higher response amplitudes on the right hand. The results indicated a coincidence between the degree of phasic electrodermal activity and reciprocal hemispheric influences, implying hemispheric interactions in mechanisms that control phasic reactivity, habituation, and attention.

A spinal sympatho-inhibitory action of chlorpromazine and haloperidol in the cat.

Abstract Intravenous administration of chlorpromazine (0.03–l.0 mg/kg) or haloperidol (0.03–1.0 mg/kg) resulted in a dose-dependent inhibition of spinally-evoked electrodermal responses (EDRs) in the anesthetized spinal cat. These findings suggest that chlorpromazine and haloperidol act at the level of the spinal cord to depress activity in the sympathetic-cholinergic electrodermal system. Neither drug had a significant effect on pre- or postganglionically-evoked EDRs, further indicating their central action.

Lateralization in the Electrodermal System as a Function of Cognitive/Hemispheric Manipulations

ABSTRACTThree experiments examined patterns of bilateral differences in skin conductance as a function of cognitive tasks intended to produce specific manipulations in the relative activation of the two hemispheres. Experiments 1 and 2 employed right‐handed subjects, and examined the effects of Verbal (left‐hemispheric) and Spatial (right‐hemispheric) tasks. In both experiments response amplitudes were substantially smaller in the hand contralateral to the more activated hemisphere than in the ipsilateral hand. Experiment 2 also examined the effects of Music and Number tasks, intended to produce a similar level of activation in the two hemispheres: these tasks were not accompanied by reliable bilateral differences in electrodermal activity. Experiment 3 consisted of a replication of Experiment 2 with subjects (sinistrals) known, as a group, to exhibit little functional hemispheric specialization. In these subjects, bilateral electrodermal differences did not vary systematically as a function of tasks. These findings argue strongly for the presence of lateralized cortical influences on electrodermal activity, and their implications for psychological and neurophysiological models of electrodermal functioning are discussed.

Potentiation of two sympathetic reflexes by yohimbine hydrochloride

Yohimbine hydrochloride (0.5 mg kg i.v.) resulted in a pronounced increase in electrodermal (sympathetic-cholinergic) and nictitating membrane reflexes in intact anaesthetized and decerebrate unanaesthetized cats. Potentiation by yohimbine of these two sympathetic reflexes was not an indirect action due to lowering of blood pressure as the effect was still observed in baroreceptor denervated cats. Yohimbine had no effect on electrodermal reflexes evoked in spinal preparations nor did it alter the peripheral frequency-response curves for either effector. Yohimbine also appeared to increase central tonic activity with regard to basal skin potential, nictitating membrane basal tone and heart rate levels. These results suggest that yohimbine may be acting to antagonize central inhibitory tone to both of these autonomic systems. With regard to the electrodermal system, yohimbine may be acting at the level of the spinal cord to block tonic inhibition descending from the lower brain stem.

Orienting and defensive responding in the electrodermal system: palmar-dorsal differences and recovery rate during conditioning to potentially phobic stimuli.

ABSTRACTIt was suggested that the effects of fear‐relevant pictures as conditioned stimuli (CSs) for electrodermal responses may be explained if it is assumed that they produce conditioned defense responses (DRs), as opposed to the orienting responses (ORs) that are produced by fear‐irrelevant stimuli. Some propositions in Edelberg's theory of electrodermal activity were used to differentiate between DRs and ORs in a test of this hypothesis. Groups of subjects were conditioned to fear‐relevant (snakes and spiders) or fear‐irrelevant (flowers and mushrooms) CSs by means of an aversive (electric shock) or a non‐aversive (imperative signal for a reaction time (RT) task) unconditioned stimulus in long interval differential paradigms. The neutral‐shock, phobic‐RT, and neutral‐RT groups showed no palmar‐dorsal differences either in magnitude, probability or amplitude, and no conditioning in the recovery rate measure. However, the phobic‐shock group showed a peak of dorsal magnitude early in training that subsequently habituated whereas the palmar magnitude data indicated a gradual conditioning effect that lasted throughout the 20 extinction trials. In addition, it showed slower recovery to the reinforced than to the nonreinforced stimulus. These data are taken as support for the hypothesis.

Habituation and the structure of the electrodermal system.

ABSTRACTThe intercorrelatons among fifteen common SRR variables were investigated on two samples of male subjects in a standard habituation paradigm. The first group (N = 212) was made up of 149 prisoners and 63 controls (mean age = 28yrs) while the second group (N =84) were all twins (mean age=25 yrs). All subject received 21 auditory stimuli at an ISI of 33 sec. Each stimulus was sinusoidal, at 1000 Hz. of 1 see duration and at 95 (IB ire 20 N/cm2). The fifteen SRR measures taken from each subject included mean and change scores for basal conductance, response amplitude, spontaneous fluctuation frequency, number of responses, and onset, peak and half‐recovery latencies. The variables were Intel‐correlated and factor analyzed. The.05 rejection region was adopted in all statistical tests. A fun h simple structure for the variables was demonstrated. Hit' results emphasized the importance of a large general reactivity component in must of these variables. Within‐subject correlations were calculated and found to be different from across‐subject correlations. It is suggested that under constant stimulus conditions subjects display different but individually topical SCR shapes which reduce in size during habituation.

Contingency theory and classical autonomic excitatory and inhibitory conditioning: some problems of assessment and interpretation.

ABSTRACTThe primary aims are to elaborate on and clarify two general issues which are raised in the context of assessing contingency theory: (a) the operational requirements and the psychophysical considerations for assessing autonomic excitatory and inhibitory factors in Pavlovian conditioning, and (b) the topic of the appropriate CR specification in the autonomic electrodermal system. Our substantive conclusion, based on an evaluation of the methodology of available human autonomic studies, is that there is no empirical support for the contingency truly random control procedure. In addition, contrary to the suggestion of striking analogies with the skeletal eyelid system, a latency criterion should not be used to deny associative status to first‐interval electrodermal responses, provided that these do satisfy conventional behavioral criteria for associative conditioning, e.g., discrimination.

Electrodermal lability and recovery of habituated or

The study examined the relationship between individual differences in non-specific electrodermal responding and recovery of the electrodermal component of the orienting reaction (OR) with variation in an auditory stimulus. Following habituation to criterion, 50 male Ss were presented with either the habituating stimulus (1000 Hz) or a stimulus of 1350 Hz. Ss classified as “labiles” on the basis of high levels of non-specific responding during a resting period prior to habituation showed significant increase in electrodermal response on the change trial over control level. For “stabiles”, Ss showing low levels of non-specific responding, the difference between control and change trials was not significant. It is suggested that strength of inhibitory control within the electrodermal system modifies the effect of stimulus variation on recovery of the habituated electrodermal OR.