Basal Skin Conductance Research Articles

Alterations in HPA-axis and autonomic nervous system functioning in childhood anxiety disorders point to a chronic stress hypothesis

Background: It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). Methods: The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. Results: The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Conclusions: Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia.

Alterations in HPA-axis and autonomic nervous system functioning in childhood anxiety disorders point to a chronic stress hypothesis.

It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia.

Skin conductance as a marker of pain in infants of different gestational age

To assess the use of skin conductance as an objective measure of pain in infants of different gestational age. A second aim was to investigate the relationship between skin conductivity and selected physiological and behavioural variables (oxygen saturation, heart rate and behavioural state). Infants were divided according to gestational age into the following 3 groups; group A: 25+0-31+6 weeks (13 infants), group B: 32+0-35+6 weeks (25 infants), group C: 36+0-41+6 weeks (19 infants). The pain stimulus was blood sampling. The most sensitive parameter for describing changes in skin conductance related to pain was peak per second. No other parameter correlated with the physiological variables chosen. The results showed that the inability to determine basal skin conductance is a crucial disadvantage to practical application. The lack of correlation between conductance parameters and gestational age is surprising. We conclude that the Peak per Second is the best parameter for evaluating skin conductance in infants and it is not influenced by gestational age. Peaks per Second correlate only with Prechtl's Scale of behavioural state and not with the physiological parameters chosen.

Effect of Muscle Relaxation Training as a Function of Improvement in Attentiveness in Children

Sixty-four primary school going boys of the Indian sub-continent in the age range of 9-12 years having high trait anxiety and attention-deficits, volunteered as the participants in this experiment. Half of them were recruited from residential academic institution in Bangladesh, while their counterparts were selected from identical residential academic institution in India. For the experiment proper, in both of the set-ups participants were categorised into two groups, viz. Gr. A (Control group, not exposed to any intervention program) and Gr. B (Experimental group, received Abbreviated version of Progressive Muscle Relaxation – (APMR training). Both groups were subjected to the pre-intervention assessment of attentive capacity, electrical muscle potentiality and different variables of skin conductance measure (as indices of heightened emotionality). Thereafter Gr. B boys were introduced to the training of APMR (monitored training of APMR for 15 min.s/day; three days/week) for a period of two months during the afternoon sessions under the guidance of a qualified and trained instructor. Post-intervention assessment and follow up assessment (after two months), on all the aforesaid variables however revealed that in both of the set-ups (in Bangladesh as well as in India) training and subsequent monitored long-term practice of APMR was found effective in reducing anxiety level and in developing better attentive capacity in the children of the both of the countries, who were exposed to the respective intervention. Improvement in frontalis muscle tension and in the basal skin conductance level along with higher autonomic habituation as an impact of long-term and regulated APMR training was suggested as facilitator of sustainable improvement in attentive capacity in the children.

Cortisol and Children’s Adjustment: The Moderating Role of Sympathetic Nervous System Activity

We examined relations among cortisol, markers of sympathetic nervous system (SNS) activity (including salivary alpha-amylase and skin conductance level), and children's adjustment. We also tested the Bauer et al. (Journal of Developmental and Behavioral Pediatrics, 23(2), 102-113, 2002) hypothesis that interactions between the SNS and cortisol would be associated with internalizing and externalizing problems. Saliva samples were obtained from 8- to 9-year-olds before and after a laboratory assessment battery, and were assayed for cortisol and alpha-amylase (sAA). Basal skin conductance level (SCL) was measured during resting conditions. Parents reported on child adjustment. Interactions between basal SNS and cortisol levels explained moderate amounts of unique variance in children's externalizing and internalizing problems. More specifically, higher basal cortisol levels were positively associated with higher internalizing and externalizing problems among children with higher SNS activity, as compared to children with lower SNS activity. Findings underscore the utility of including information about the coordination between hypothalamic-pituitary-adrenal (HPA) and SNS activity in biosocial models of atypical child development.

Sympathetic (electrodermal) activity during repeated maximal rectal distensions in patients with irritable bowel syndrome and constipation

Irritable bowel syndrome (IBS) is associated with visceral hypersensitivity, stress and autonomic dysfunction. Sympathetic activity during repeated events indicates excitatory or inhibitory mechanisms such as sensitization or habituation. We investigated skin conductance (SC) during repetitive rectal distensions at maximal tolerable pressure in patients with IBS and chronic constipation. Twenty-seven IBS patients, 13 constipation patients and 18 controls underwent two sets of isobaric rectal distensions. First, maximal tolerable distension was determined and then it was repeated five times. Skin conductance was measured continuously. Subjective symptom assessment remained steady in all groups. The baseline values of SC were higher in IBS patients than in patients with constipation and significantly lower in constipation patients than in controls. The maximal SC response to repetitive maximal distensions was higher in IBS patients compared with constipation patients. The amplitude of the initial SC response decreased successively with increased number of distensions in patients with IBS and constipation but not in controls. Irritable bowel syndrome and constipation patients habituated to maximal repetitive rectal distensions with decreasing sympathetic activity. Irritable bowel syndrome patients had higher sympathetic reactivity and baseline activity than constipation patients. A lower basal SC in constipation patients compared with controls suggests an inhibition of the sympathetic drive in constipation patients.

Prediction of adolescent outcome in children with disruptive behaviour disorders

In this preliminary study we explored the predictive influence of various family, psychological, demographic, and neurobiological characteristics on the persistence of antisocial behaviour in adolescence. Existing data were combined with case-records in a sample of 47 disruptive behaviour disordered (DBD) children who had been treated in in-patient and/or day-treatment units when they were between seven to 12 years old. Parent-rated and self-rated externalizing problem scores and the presence of a DBD diagnosis served as the outcome measures in adolescence. We used linear regression analyses to examine the predictors of adolescent outcome. A lower basal skin conductance level (SCL) was repeatedly found to predict poor adolescent outcome, either when rated by parents or by participants themselves. In addition, comorbid attention-deficit hyperactivity disorder, one aspect of performance on the door-opening task, and a mother of low socioeconomic status also predicted that a child would have more antisocial problems in adolescence, depending on the type of outcome measure. Results of this study support the fearlessness theory, according to which low activity of the autonomous nervous system, as manifested by low SCL, is related to the effectiveness of socializing punishment and accordingly to poor socialization and adolescent outcome.

AIR POLLUTION AND HEALTH HAZARDS IN HUMAN SUBJECTS: PHYSIOLOGICAL AND SELF-REPORT INDICES

This study was undertaken to determine the effects of air pollution on the physical and mental health of human adult subjects. Three different areas of Calcutta Metropolis, namely industrial, commercial and residential regions, were selected following the criteria given by National Environment Engineering Research Institute, West Bengal Pollution Control Board and Calcutta Corporation. Subjects were selected randomly and were matched in age, sex, education, occupation, marital status, family type, etc. with the exception that they were the residents in the three different areas. Migrated subjects were excluded from this study. Subjects investigated were reported to be free from any neurological deficit. Psychological (STAI, Stressful life events, Cornell Medical Index, Personality questionnaire) and physiological (Basal skin conductance) measures were employed with each of these subjects in two sessions. Results revealed that residents of the industrial area were highly affected in terms of physical and mental health. They complained of throat and eye irritation, respiratory problems, tension and anxiety much more than the inhabitants of the residential area. Inhabitants of the commercial area fell in-between. Appropriate theoretical interpretation of the data have been made.

Nerveblocks by local anaesthesia also change body-mind interdependencies and effect structural reactions of mind

Skin conductance (SC) has been previously used to measure acute post-operative pain in adults and older children (> 1 year old).We have investigated the ability of SC to predict the severity of post-operative pain scores in the exclusively infant population.Infants (ages 6–12 months) scheduled for elective surgery were recruited for the study. Data for behavioral pain scores and SC values — frequency of electrodermal responses per second (EDR/s), peak and basal levels, were recorded in the post-anesthesia care unit (PACU). Blood samples were collected for genomic studies, including single nucleotide polymorphisms (SNP) in morphine opioid receptor (MOR) A118G and the catechol-O-methyltransferase (COMT) G1947A genes.31 infants, mean age 8.9 months (± 1.9); mean weight 8.5 kg (± 1.1) were included in the final study analysis. With every 0.1 unit increase in peak values noted on SC, the odds of higher pain scores were found to be 5% greater (p = 0.03). For predictability of moderate to severe pain, the area under the curve, sensitivity and specificity were 0.64, 90.9% and 51.4% respectively for peak values and 0.66, 54.5% and 79.4% respectively for EDR/s values. Genotyping performed in 16 out of 31 infants demonstrated that the carriers of MOR 118G allele had consistently higher basal SC values in the PACU.Peak SC values may serve as indicators of unmitigated pain. Further studies are needed to fully investigate the effect of MOR A118G SNP on the post operative pain scores and SC values in the larger infant population in order to validate both the clinical significance of the skin conductance for routine pain assessment in infants and the observed genetic effect.

Skin conductance response after 6-hydroxydopamine lesion of central noradrenaline system in cats

Absence of skin conductance response (SCR) is a psychophysiological sign frequently observed among schizophrenic patients. This alteration of electrodermal activity can be reproduced in cats and rats by intraventricular administration of 6-hydroxydopamine (6-OHDA), a neurotoxin selectively destroying catecholamine neurons. The findings appears to be quite consistent with the catecholamine hypothesis of schizophrenia. To determine which catecholamine system—the dopamine (DA) or the noradrenaline (NA)—is responsible for the induction of this abnormality, the same dose of 6-OHDA was microinjected to either the ventral tegmental area (VTA, n = 3), through which most DA fibers ascend, or to the ascending noradrenergic bundle (ANB, n = 3), through which most NA fibers ascend. Four cats remained intact as a control for later brain catecholamine estimation. The skin conductance of all pretreatment intact cats ( n = 10) showed not only spontaneous fluctuations but also SCRs to auditory stimuli (5 kHz, 100 dB, 1 sec) which habituated with repetition. In contrast, ANB-lesioned cats showed a complete abolition of auditory SCRs, few spontaneous fluctuations, and a low basal skin conductance level. These abnormalities were statistically significant. On the other hand, no change was found in the skin conductance activity of the VTA-lesioned cats. Catecholamine estimation after the experiment confirmed selective destruction of the appropriate system corresponding to each type of lesion. These findings are discussed in the context of the DA or NA theory of schizophrenia, and involvement of the NA system in the pathogenesis of this illness is suggested.

Reliability of psychophysiological assessment within temperament groups

Four groups of 16 people selected for their relatively extreme scores (greater or equal to 1 S.D. from the mean) on both the E and N scales of the Eysenck Personality Inventory visited the laboratory for four separate but identical testing sessions. Three physiological indices were recorded at each session: heart rate (HR), basal skin conductance level (SCL), and the number of spontaneous skin conductance responses (SCR). Test-retest correlation coefficients were calculated within E X N groups across days. HR and SCR showed moderate to good reliabilities across all groups. The most interesting finding was that SCL was a consistently reliable index for extraverts but not for introverts. Correlations between days were statistically significant for extraverts but not for introverts. A speculative explanation for these results is that SCL is affected by cognitive activity rather than autonomic arousal perse This study suggests that there are systematic effects of temperament on physiological measures that are important and should not be relegated to error variance.

A laboratory study of temperament and arousal: A test of Gale's hypothesis

Four groups of 16 people selected for their relatively extreme scores (greater than or equal to 1 standard deviation from the mean) on both the extraversion-introversion and neuroticism-stability scales of the Eysenck Personality Inventory visited the psychophysiological laboratory for four separate but identical testing sessions. Each subject completed self-report inventories on present mood states. Heart rate, basal skin conductance level, spontaneous skin conductance responses, and absolute auditory threshold were recorded. Evidence of an overall decrease in arousal across testing sessions was found for the physiological data and the self-report data. These results support Gale's hypothesis that there are arousal properties associated with the psychophysiological laboratory per se that diminish with familiarity. In support of Eysenckian theory, temperament × stimulation level interactions were found. Extraverts displayed a decrease in physiologically measured arousal across days while introverts displayed no appreciable change. These results support Gale's hypothesis that arousal differences between introverts and extraverts will only emerge under conditions of moderate stimulation. Only on the first day of testing were there significant differences between neurotics and stable individuals on measured tension/anxiety, a result which could confound performance or behavioral measures used in one-session experiments. The results of this study support the use of measures of temperament in psychological research. Levels of stimulation interact with differences in temperament, and level of stimulation is evidently highest on an individual's first visit to the laboratory.

Is Washing a Prepared Ritual?

Abstract Though numerous acts can be carried out in a ritualistic fashion, compulsive ritualising very often involves washing or cleaning behaviour. To explain this selectivity and non-randomness of compulsive ritualising, it was hypothesised that washing behaviour is a form of displacement behaviour and, as such, is intrinsically discomfort-reducing. This hypothesis was tested by having normal subjects either wash or rub their hands after a discomfort-induction procedure. The induction of discomfort was successful in that self-reported mood deteriorated and basal skin conductance increased. A significant improvement in mood occurred when subjects washed their hands. However, the same effect occured when controls rubbed their hands. The data do not support the hypothesis that washing behaviour, has an intrinsically discomfort-reducing effect.

Labour, delivery and basal skin conductance (BSC) in the newborn : Malcolm L. Chiswick and Dawn Bennett, North Western Regional Perinatal Centre, St. Mary's Hospital, Whitworth Park, Manchester, U.K.

Labour, delivery and basal skin conductance (BSC) in the newborn : Malcolm L. Chiswick and Dawn Bennett, North Western Regional Perinatal Centre, St. Mary's Hospital, Whitworth Park, Manchester, U.K.

Relation of neuroleptic dose and tardive dyskinesia to attention, information-processing, and psychophysiology in medicated schizophrenics.

Relationships of neuroleptic dosage and tardive dyskinesia with measures of attentional, information-processing, and psychophysiological dysfunctions in medicated chronic schizophrenics were explored by correlational and stepwise multiple-regression analysis. High neuroleptic dosage was found to be associated with increased reaction time, reduced span of apprehension, low basal skin conductance level, and reduced skin conductance reactivity. Severe abnormal involuntary movements were associated with increased eye-tracking dysfunction, increased scanning eye-movement rate, increased reaction time, and reduced skin conductance reactivity. These findings led to the hypothesis that neuroleptic dosage and tardive dyskinesia may be sources of error variance in the measurement of attentional, information-processing, and psychophysiological functions in schizophrenics.

Effects of sexual versus fear arousal on alcohol consumption in college males

To compare the effects of pleasant and aversive arousal on alcohol consumption, 18 male undergraduates had three weekly sessions to separately view erotic, mutilation or neutral slides in a simulated memory experiment. Following exposure to the slides, they received access to alcoholic and nonalcoholic beverages, which were presented to half the subjects in a taste rating task, and to half as the result of engaging in an operant lever-press task. Subjects believed these tasks to be distractors during a purported retention interval. Self-report instruments and basal skin conductance confirmed the success of the affective manipulations. However, only the subjects using the taste task after viewing erotic slides significantly increased alcohol consumption. These results question a tension reduction model of drinking and qualify the contribution of autonomic arousal to motivation for drinking.

Operant GSR conditioning with cool air reinforcement.

Two groups of 20 Ss each run individually in a soundproff chamber heated to 115 F and humidified to 100%. Ss in the experimental group received brief presentation of cool air contingent upon wmitted GSRs during 20 min of acquisition. Control Ss were matched on at a time in operant rate and were yoked one at a time to receive the cool air on a response-independent schedule. Both groups increased significantly in rate of unelicited GSRs during acquisition, with the experimental Ss' curve rising more rapidly and both groups attaining equivalent terminal levels. During extinction, the groups maintained high levels of responding and did not differ. Examination of basal skin conductance data ruled our an activation hypothesis. In the control Ss, terminal response frequency was significantly correlated with percentage of fortuitous response-contigent reinforcement. It was concluded that both croups were conditioned, with the controls receiving intermittent reinforcement sufficiently often to elevate their responding. The cool air was judged to be an effective reinforcer of unelicited GSRs, perhaps more effective than those used in previous studies.

Autonomic arousal and performance during sixty hours of sleep deprivation.

The paper reports the performance on 6 tests of the battery used by Reitan designed to evaluate brain dysfunction, as well as autonomic arousal measured by heart rate and basal skin conductance, for 12 Ss during 60 hr. of sleep deprivation. Twelve control Ss were tested at equal intervals without sleep loss. The performance on the psychological tests remained unimpaired during the early phases of sleep loss while heart rate and skin conductance increased; the deficit in performance became evident in the last phase of the deprivation period when heart rate and skin conductance declined.

Electrodermal correlates of hyperactivity in children.

ABSTRACTBasal skin conductance, non‐specific GSRs, and specific GSRs were studied during 2 experimental sessions with two groups of 12 hyperkinetic children each and a group of 12 matched normal controls. Hyperkinetic children were found to have lower basal skin conductance, fewer and smaller non‐specific GSRs, and smaller specific GSRs than those of normal children. Stimulant drugs, which were administered to one group of hyperkinetic children, tended to raise basal level conductance and non‐specific GSR activity toward the levels of normal children. A tentative neurophysiological hypothesis is offered to account for these data as well as the clinical observations that stimulant drugs are effective in the treatment of hyperkinetic children.

Skin conductance and reaction time with and without knowledge of results

Skin resistance was monitored during a simple reaction-time task carried out by two groups of Ss. Both groups were rewarded but only one group was given knowledge of results. Mean log basal conductance level was negatively and significantly related to reaction time in the no-knowledge-of-results group. No such relationship was found for the knowledge-of-results group, which had significantly faster reaction times. There was no significant difference between mean log basal conductance level in the two groups. The results suggest that basal skin conductance level does not reflect activity in a postulated reinforcement system.