Skin Conductance Data Research Articles

Irritable bowel syndrome and symptom severity: Evidence of negative attention bias, diminished vigour, and autonomic dysregulation

ObjectiveTo determine if cognitive processing, and subjective and physiological responses to stress and relaxation differed between an irritable bowel syndrome (IBS) group and control group. How these variables relate to the severity of IBS symptoms was also determined. MethodsTwenty-one IBS participants and 20 controls provided cognitive (attention and processing), subjective (perceived stress and vigour), and physiological (heart rate, blood pressure, and skin conductance) data during a relaxation and stress phase. Logistic regression analyses determined which variables are related to the IBS group and hierarchical linear regression assessed how the variables are related to the severity of IBS symptoms. ResultsSubjective and cognitive factors (drowsiness at baseline, total vigour, and reduced Stroop colour-naming accuracy for negative words) are significantly related to IBS, χ2 (3, N=41)=23.67, p<.001, accurately categorising 85% of participants. IBS symptom severity was associated with both subjective (drowsiness at baseline and a smaller reduction in tiredness from relaxation to stress) and physiological (smaller increase in systolic blood pressure from baseline to stress phase and lower skin conductance at baseline) variables. This model predicted IBS severity, F (4, 16)=11.20, p<.001, and accounted for 74% of the variability in scores. ConclusionsA negative attention bias, which may be related to a negative self-schema, as well as perceived low vigour were important in categorising IBS. Low subjective vigour and reduced physiological reactivity to both relaxation and stress conditions were associated with IBS severity, suggestive of illness-related allostatic load.

Moderating Effects of Coping on Associations between Autonomic Arousal and Adolescent Internalizing and Externalizing Problems

Few published studies have looked at the moderating role of coping styles on the association between stress reactivity and internalizing/externalizing problems despite theory suggesting that particular constellations of stress reactivity and coping may be uniquely problematic. The present study aimed to test the interactive effects of coping and psychophysiology on self- and parent-report broad-spectrum problems in a normative adolescent sample. Sixty-six late adolescents (ages 16–17; 60% female, 13% ethnic minority) completed questionnaires on coping, stressful life events, and behavioral/emotional problems, with parents also providing data on problems. In addition, skin conductance and heart rate data were obtained during a brief interview designed to elicit the feeling of reexperiencing a recent stressful experience. Path analytic results suggested evidence for several interaction effects between coping and skin conductance. Most commonly, the pattern of effects was consistent with a buffering effect for productive (or problem-focused) coping strategies against elevated internalizing and externalizing problems for individuals who demonstrated high physiological stress reactivity. Evidence for interaction effects related to respiratory sinus arrhythmia was less frequent and less consistent with a priori hypotheses. Although our cross-sectional results should be interpreted cautiously, the interactions reported here suggest that improving coping skills may be particularly beneficial for youth with high psychophysiological arousal.

Sternal skin conductance

This study aims to examine the accuracy of a new sternal skin conductance (SSC) device in measuring hot flashes and to assess the acceptability of the device by women. Three small descriptive pilot studies were performed using two sequential prototypes of the SSC device developed by an engineering device company in the Midwest. The devices were worn either in a monitored setting for 24 hours or in an ambulatory setting for 5 weeks. During the study period, women recorded hot flashes in a prospective hot flash diary and answered questions about the acceptability of wearing the SSC device. The first prototype was not able to collect any analyzable skin conductance data owing to various malfunction issues, including poor conductance and battery failure. However, 16 women wore the device for 5 weeks and reported that wearing the device was acceptable, although 31% stated that it interfered with daily activities. Hot flash data from the second prototype revealed a 24% concordance rate between self-reported and device-recorded hot flashes. Findings from these studies support discordance between device-recorded and self-reported hot flashes. In addition, the studies reveal further limitations of SSC monitoring, including difficulties with data collection and lack of consistency in interpretation. Based on these results and other recent trials identifying issues with SSC methodology, it is time to find a better physiologic surrogate measure for hot flashes.

Pervasive competition between threat and reward in the brain

In the current functional MRI study, we investigated interactions between reward and threat processing. Visual cues at the start of each trial informed participants about the chance of winning monetary reward and/or receiving a mild aversive shock. We tested two competing hypothesis: according to the 'salience hypothesis', in the condition involving both reward and threat, enhanced activation would be observed because of increased salience; according to the 'competition hypothesis', the processing of reward and threat would trade-off against each other, leading to reduced activation. Analysis of skin conductance data during a delay phase revealed an interaction between reward and threat processing, such that the effect of reward was reduced during threat and the effect of threat was reduced during reward. Analysis of imaging data during the same task phase revealed interactions between reward and threat processing in several regions, including the midbrain/ventral tegmental area, caudate, putamen, bed nucleus of the stria terminalis, anterior insula, middle frontal gyrus and dorsal anterior cingulate cortex. Taken together, our findings reveal conditions during which reward and threat trade-off against each other across multiple sites. Such interactions are suggestive of competitive processes and may reflect the organization of opponent systems in the brain.

Additional support for the existence of skin conductance responses at unconditioned stimulus omission

The existence of a skin conductance response to an expected but omitted aversive stimulus has recently been challenged. To counter this claim, we provide a review of the literature and a temporal analysis of two independent skin conductance data sets during aversive conditioning and extinction that demonstrates a consistent and reproducible skin conductance response at omission of an anticipated aversive stimulus. The validity of this so-called unconditioned stimulus (US) omission response is relevant for skin conductance modeling in the context of neuroimaging and more generally for conditioning theory.

No evidence for a negative prediction error signal in peripheral indicators of sympathetic arousal

Recently, the existence of a prediction error signal to the omission of expected punishment in skin conductance recordings has been posited. Here, we re-analyse an existing dataset on aversive delay conditioning and find no evidence for such a signal. We discuss methodical reasons for this discrepancy and technical implications for estimation of central processes from skin conductance data.

Improved Temporal Resolution Heart Rate Variability Monitoring—Pilot Results of Non-Laboratory Experiments Targeting Future Assessment of Human-Computer Interaction

This paper outlines the INTERFACE software ergonomic evaluation methodology and presents new validation results. The INTERFACE methodology is based on a simultaneous assessment of heart rate variability, skin conductance, and other data. The results of using this methodology on-site, in a non-laboratory environment indicate that it is potentially capable of identifying quality attributes of elements of software with a temporal resolution of only a few seconds. This paper presents pilot results supporting this hypothesis, showing empirical evidence in spite of the definitely non-laboratory environment: they indicate that the method is robust enough for practical usability tests. Naturally, in the future these pilot results will have to be followed with further laboratory-based verification and refinement. This paper focuses only on some characteristics of this method, not on an actual analysis of human-computer interaction; however, its results can establish a future practical and objective event-related analysis of software use.

Resonances in the cardiovascular system caused by rhythmical muscle tension.

Paced 0.1 Hz breathing causes high-amplitude HR oscillation, triggering resonance in the cardiovascular system (CVS). This oscillation is considered to be a primary therapeutic factor in HRV biofeedback treatments. This study examined whether rhythmical skeletal muscle tension (RSMT) can also cause 0.1 Hz resonance in the CVS, and compared oscillatory reactivity in CVS functions caused by RSMT and paced breathing (PB). Sixteen young healthy participants completed five tasks: baseline, three RSMT tasks at frequencies of 0.05, 0.1, and 0.2 Hz, and a 0.1 Hz PB task. ECG, respiration, finger pulse, and skin conductance data were collected. Results showed that 0.1 Hz RSMT as well as 0.1 Hz PB triggered resonance in the CVS and caused equivalent oscillations in all measured CVS functions, although in women, RSMT compared to PB caused lower HR oscillation. Clinical application of 0.1 Hz RSMT is discussed.

257 Water Content in Infant Stratum Corneum

Objective: To determine the water content of infant stratum corneum (SC) as compared to adult and identify the sources of differences. Methods: We have acquired in vivo Raman spectra from the forearm skin of 15 infants (3-24 months) and their biological mothers. The Raman spectra were analyzed for the water content, the thickness of SC, and the concentration of components of natural moisturization factor (NMF). We also collected skin conductance data on the forearm of 67 infants of the same age and their mothers. Results: As previously reported conductance values and water concentration profiles are significantly higher in infant skin compared to adult. In agreement with published data from confocal microscopy, Raman data also show that infant SC is 30% thinner than adult. Even after accounting for the differences in SC thickness our data show that water content in the top layers of the SC is still significantly higher in infants compared to adults (20% more at the top quarter of SC). NMF analysis showed that although adults have more amino acids, infants have significantly more lactate in their SC. Conclusions: Infant SC contains more water than adult. Lactate may be responsible for at least part of this increased water content. Water stored in microrelief lines may be an additional explanation for the higher skin conductance values in infant skin.

Emotional Responses During Social Information Seeking on Facebook

Based on existing research on social networking and information seeking, it was proposed that Facebook.com use could be conceptualized as serving two primary goals: passive social browsing (i.e., newsfeeds) and extractive social searching (i.e., friends' profiles). This study explored whether these categories adequately reflect Facebook use and whether they moderate physiological indicators of emotion. Thirty-six participants navigated Facebook.com while their on-screen activity and physiological responses associated with motivation and emotion were recorded. Results showed that the majority of screens encountered during Facebook use could be categorized as devoted to social browsing or social searching. Participants spent more time on social browsing than they spent on social searching. Skin-conductance data indicated that sympathetic activation diminished during the course of both social browsing and social searching. Facial EMG data indicated that participants experienced more pleasantness during the course of social searching than they experienced during social browsing. These results are discussed in terms of existing social-networking research and an evaluative space model of emotion.

Decomposition of skin conductance data by means of nonnegative deconvolution

Skin conductance (SC) data are usually characterized by a sequence of overlapping phasic skin conductance responses (SCRs) overlying a tonic component. The variability of SCR shapes hereby complicates the proper decomposition of SC data. A method is proposed for full decomposition of SC data into tonic and phasic components. A two-compartment diffusion model was found to adequately describe a standard SCR shape based on the process of sweat diffusion. Nonnegative deconvolution is used to decompose SC data into discrete compact responses and at the same time assess deviations from the standard SCR shape, which could be ascribed to the additional process of pore opening. Based on the result of single non-overlapped SCRs, response parameters can be estimated precisely as shown in a paradigm with varying inter-stimulus intervals.

Sex-specific association between psychopathic traits and electrodermal reactivity in children.

This study investigated the relationship of skin conductance response (SCR) to a child psychopathy measure. Blunted electrodermal activity is a theoretically important characteristic of psychopathy, but it has not been fully explored in preadolescents or females. The authors tested the hypothesis that reduced SCR magnitude is associated with psychopathic-like traits in boys and girls. Participants were drawn from an ethnically diverse community sample of 9- to 10-year-old twins. Given the fact that members of each twin pair were rated by the same individual (i.e., their caregiver) on the Child Psychopathy Scale, the authors examined individual differences at the within-family level. Skin conductance data were collected during a passive auditory task consisting of 75-dB tones as well as miscellaneous sounds (e.g., baby cries, bird noises, and speech-like stimuli). Reduced SCR magnitude (hyporeactivity) was characteristic only of boys with higher psychopathy scores. More specifically, electrodermal hyporeactivity was linked to the interpersonal facet of psychopathy, suggesting that it is a biological marker of a manipulative and deceitful orientation in males. No association was found between SCRs and psychopathic traits in girls, indicating the importance of sex specific etiologies of psychopathy in childhood.

A complex physiology-based empirical usability evaluation method in practice

This paper outlines the INTERFACE usability evaluation methodology developed by researchers of our department. It is based on the simultaneous assessment of Heart Period Variability (HPV), Skin Conductance (SC), and other data. One of the highlights of this methodology is its capability to identify quality attributes of software elements with a time-resolution of only a few seconds: in particular cases it can assess 2- or 3-second events. The Department of Ergonomics and Psychology at the Budapest University of Technology and Economics carried out applied research projects assessing very various software. After these, we can show different types of typical software problems identified by our method. The method of analysis allows us not only to decide what types of problems are significant to the users; however, on the other hand, the method allows us to decide, to what extent the found problems and their assessed severity concern all the users in general, or how these things depend on the type and characteris tics of the users.

Exploring the Potential of Short-Time Fourier Transforms for Analyzing Skin Conductance and Pupillometry in Real-Time Applications

The development of real-time predictors of mental workload is critical for the practical application of augmented cognition to human-machine systems. This paper explores a novel method based on a short-time Fourier transform (STFT) for analyzing galvanic skin conductance (SC) and pupillometry time-series data to extract estimates of mental workload with temporal bandwidth high-enough to be useful for augmented cognition applications. We tested the method in the context of a process control task based on the DURESS simulation developed by Vincente and Pawlak (1994; ported to Java by Cosentino,&amp; Ross, 1999). SC, pupil dilation, blink rate, and visual scanning patterns were measured for four participants actively engaged in controlling the simulation. Fault events were introduced that required participants to diagnose errors and make control adjustments to keep the simulator operating within a target range. We were interested in whether the STFT of these measures would produce visible effects of the increase in mental workload and stress associated with these events. Graphical exploratory data analysis of the STFT showed visible increases in the power spectrum across a range of frequencies directly following fault events. We believe this approach shows potential as a relatively unobtrusive, low-cost, high bandwidth measure of mental workload that could be particularly useful for the application of augmented cognition to human-machine systems.

Skin conductance responses as predictor of emotional responses to stressful life events

Preferential preattentive processing towards threat has been proposed to play a casual role in the development of anxiety, mainly because it reliably predicts emotional responding to stressful events. However, in the investigation of the predictive value of preferential preattentive processing towards threat, the emotional Stroop task has exclusively being used. This study was designed to prospectively investigate the predictive value of skin conductance reactivity in response to masked (i.e., preattentively perceived) threatening pictures on emotional responding following stressful life events. To collect skin conductance data, the picture perception task was administered to 136 police recruits due to enroll into active duty within 2–4 months. To assess psychological distress following emotionally stressful life events, the impact of event scale were administered approximately 24 months later. Controlling for trait anxiety, analyses indicated that enhanced skin conductance reactivity in response to masked threatening pictures (relative to neutrals) was a strong predictor of emotional responding to stressful life events. This finding support preferential preattentive processing towards threat as a relatively independent factor predictive of emotional responding.

Covariations among fMRI, skin conductance, and behavioral data during processing of concealed information

Imaging techniques have been used to elucidate the neural correlates that underlie deception. The scientifically best understood paradigm for the detection of deception, however, the guilty knowledge test (GKT), was rarely used in imaging studies. By transferring a GKT-paradigm to a functional magnetic resonance imaging (fMRI) study, while additionally quantifying reaction times and skin conductance responses (SCRs), this study aimed at identifying the neural correlates of the behavioral and electrodermal response pattern typically found in GKT examinations. Prior to MR scanning, subjects viewed two specific items (probes) and were instructed to hide their knowledge of these. Two other specific items were designated as targets and required a different behavioral response during the experiment and eight items served as irrelevant stimuli. Reaction times and SCR amplitudes differed significantly between all three item types. The neuroimaging data revealed that right inferior frontal and mid-cingulate regions were more active for probe and target trials compared to irrelevants. Moreover, the differential activation in the right inferior frontal region was modulated by stimulus conflicts. These results were interpreted as an increased top-down influence on the stimulus-response-mapping for concealed and task-relevant items. Additionally, the influence of working memory and retrieval processes on this activation pattern is discussed. Using parametric analyses, reaction times and SCR amplitudes were found to be linearly related to activity in the cerebellum, the right inferior frontal cortex, and the supplementary motor area. This result provides a first link between behavioral measures, sympathetic arousal, and neural activation patterns during a GKT examination.

Artificial time constraints on the Iowa Gambling Task: The effects on behavioural performance and subjective experience

In the last decade, the Iowa Gambling Task (IGT) has become a widely employed neuropsychological research instrument for the investigation of executive function. The task has been employed in a wide range of formats, from ‘manual’ procedures to more recently introduced computerised versions. Computer-based formats often require that responses on the task should be artificially delayed by a number of seconds between trials to collect skin-conductance data. Participants, however, may become frustrated when they want to select from a particular deck in the time-limited versions—so that an unintended emotional experience of frustration might well disrupt a task presumed to be reliant on emotion-based learning. We investigated the effect of the various types of Iowa Gambling Task format on performance, using three types of task: the classic manual administration, with no time limitations; a computerised administration with a 6-s enforced delay; and a control computerised version which had no time constraints. We also evaluated the subjective experience of participants on each task. There were no significant differences in performance, between formats, in behavioural terms. Subjective experience measures on the task also showed consistent effects across all three formats—with substantial, and rapidly developing, awareness of which decks were ‘good’ and ‘bad.’

The psychophysiology of the maternal-fetal relationship.

The enigmatic quality of the maternal-fetal relationship has been extolled throughout history with little empirical support. We apply time series analysis to data for 137 maternal-fetal pairs collected at 20, 24, 28, 32, 36, and 38 weeks gestation. Maternal heart rate and skin conductance data were digitized in tandem with fetal heart rate and motor activity. No temporal relations between fetal heart rate and either maternal variable were found, although averaged maternal and fetal heart rates were correlated from 32 weeks. Consistent temporal associations between fetal movement and maternal heart rate and skin conductance were detected. Fetal movement stimulated rises in each parameter, peaking at 2 and 3 s, respectively. Associations did not change over gestation, were unaffected by a maternal stressor, and showed within-pair stability. The bidirectional nature of the maternal-fetal relationship is considered.

Peritraumatic dissociation and physiological response to trauma-relevant stimuli in Vietnam combat veterans with posttraumatic stress disorder.

A recent study found that female rape victims with acute posttraumatic stress disorder (PTSD) who received a high score on the Peritraumatic Dissociative Experiences Questionnaire exhibited suppression of physiological responses during exposure to trauma-related stimuli. The goal of our present study was to test whether the same relationship holds true for male Vietnam combat veterans with chronic PTSD, using secondary analyses applied to data derived from a Veteran's Affairs Cooperative Study. Vietnam combat veterans (N = 1238) completed measures to establish combat-related PTSD diagnostic status, extent of PTSD-related symptomatic distress, and presence of dissociative symptoms during their most stressful combat-related experiences. Extreme subgroups of veterans with current PTSD were classified as either low dissociators (N = 118) or high dissociators (N = 256) based on an abbreviated version of the Peritraumatic Dissociative Experiences Questionnaire. Dependent variables reflected subjective distress along with heart rate, skin conductance, electromyographic, and blood pressure data when responding to neutral and trauma-related audiovisual and imagery presentations. Veterans in the current PTSD group had significantly higher dissociation scores than did veterans in the lifetime and never PTSD groups. Among veterans with current PTSD, high dissociators reported greater PTSD-related symptomatic distress than did low dissociators, but the groups did not differ with respect to physiological reactivity to the trauma-related laboratory presentations. Our results replicate the previously reported relationship between peritraumatic dissociation and PTSD status in Vietnam combat veterans. However, we found no association between peritraumatic dissociation and the extent of physiological responding to trauma-relevant cues in male veterans with chronic combat-related PTSD.

The Effects of Message Valence and Listener Arousal on Attention, Memory, and Facial Muscular Responses to Radio Advertisements

This study tested the validity of using facial electromyography (EMG) as a physiological measure of the valence of radio listeners' emotional responses to advertisements and explored the effects of message valence and listener arousal on attention and memory. A within-subjects experiment was conducted in which participants listened to ten 60-second radio advertisements that had been coded in a pretest as having either a positive or negative emotional tone. Facial EMG, heart rate, and skin conductance data were collected during exposure to the advertisements. Following exposure, participants completed free recall and recogniton memory tests. Results demonstrated the validity of using facial EMG to assess the valence of emotional response to media messages. Heart rate data suggest that negative messages receive more attention than positive ones. Furthermore, how arousing a message is appears to be a better predictor of memory than message valence.