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Skin Conductance (skin + conductance)
Terms modified by Skin Conductance Selected AbstractsSkin conductance and heart-rate responses as indices of covert face recognition in preschool childrenINFANT AND CHILD DEVELOPMENT, Issue 5 2004Kjell Morten Stormark Abstract Covert face recognition was examined in 12 young preschoolers (age range 26,48 months) by comparing their autonomic functions to slides depicting former playmates from a family nursery school that the preschoolers had attended earlier with slides of their present playmates and unfamiliar children. While all preschoolers reported corroborated overt recognition of present playmates after the experiment, only three of them did so in relation to former playmates. The distribution of yes,no responses on the overt recognition task to former playmates was not significantly different from the responses to unfamiliar children. Nevertheless, the preschoolers evidenced increased skin conductance responses (SCRs) and more pronounced heart rate (HR) deceleration to the slides depicting former classmates compared to unfamiliar children. Thus, although the preschoolers' verbal responses did not differentiate between former playmates and unfamiliar children, their autonomic functions did. These findings suggest that young children can retain memories of past experiences in an implicit form without corroborated overt recognition. Copyright © 2004 John Wiley & Sons, Ltd. [source] Skin conductance or entropy for detection of non-noxious stimulation during different clinical levels of sedationACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2007A. C. Gjerstad Background:, State entropy (SE) measures electroencephalographic signals, whereas response entropy (RE) also includes frontal electromyographic activity. In the presence of electromyographic activity, the RE index is larger than the SE index, the difference being denoted as RE-, (RE-,= RE , SE). Skin conductance (SC) may be expressed by a slow reacting variable, the mean SC level, the derivate of the mean SC level (D-SC), the number of SC fluctuations (NSCF) or the amplitude of the SC fluctuations (ASCF), which directly shows skin sympathetic nerve activity. The goal of this study was to evaluate whether these SC and entropy variables could differentiate between the responses obtained to load sound stimuli at different sedation levels before the induction of general anaesthesia. Methods:, Twenty women scheduled for gynaecological laparotomy were studied. The modified observer's assessment of alertness sedation (OAAS) was used to classify the patients' hypnotic levels. White sounds (98 dB) were given at OAAS level 5 without propofol, at OAAS levels 4,3 and 3,2 with propofol and at OAAS levels 3,2 and < 2 with propofol and remifentanil. Results:, RE and SE showed a steady decline from OAAS level 5 to level < 2 (P < 0.01). RE-, did not discriminate between any of the OAAS levels (P= NS). The mean SC level discriminated between OAAS levels 4,3 to < 2 (P < 0.01). D-SC discriminated between all the different OAAS levels (P < 0.01). NSCF discriminated between OAAS levels 5 to 3,2 (P < 0.05), but did not discriminate at OAAS level 3,2 between propofol alone or combined with remifentanil, or between OAAS level 3,2 and < 2. ASCF differentiated between OAAS levels 5 and 4 (P < 0.001) and OAAS levels 3,2 and < 2 (P < 0.05) only. Conclusion:, RE, SE and D-SC showed a similar discrimination between sound responses at the different sedation levels. [source] The impact of cigarette deprivation and cigarette availability on cue,reactivity in smokersADDICTION, Issue 2 2010Steffani R. Bailey ABSTRACT Aims This experiment was conducted to determine the impact of cigarette deprivation and cigarette availability on reactivity measures to cigarette cues. Participants Smokers were recruited who were 18 years of age or older, not attempting to quit or cut down on their smoking, smoked at least 20 cigarettes daily, had been smoking regularly for past year and had an expired carbon monoxide level of at least 10 parts per million. Design Smokers were assigned randomly to abstain from smoking for 24 hours (n = 51) or continue smoking their regular amount (n = 50). Twenty-four hours later, they were exposed to trials of either a lit cigarette or a glass of water with a 0, 50 or 100% probability of being able to sample the cue on each trial. Craving, mood, heart rate, skin conductance, puff topography and latency to access door to sample the cue were measured. Findings Both exposure to cigarette cues and increasing availability of those cues produced higher levels of craving to smoke. Deprivation produced a generalized increase in craving. There was no consistent evidence, however, that even under conditions of high cigarette availability, deprived smokers were sensitized selectively to presentations of cigarette cues. Conclusions The data suggest that, even under conditions of immediate cigarette availability, deprivation and cue presentations have independent, additive effects on self-reported craving levels in smokers. [source] Covariations among fMRI, skin conductance, and behavioral data during processing of concealed informationHUMAN BRAIN MAPPING, Issue 12 2007Matthias Gamer Abstract 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. Hum Brain Mapp 2007. © 2007 Wiley-Liss, Inc. [source] Self-Report and Psychophysiological Responses to Fear AppealsHUMAN COMMUNICATION RESEARCH, Issue 2 2009Juan R. Ordoñana This study was designed to assess the relationship between self-report and psychophysiological responses to fear appeals and behavioral changes elicited by these. Ninety-two subjects watched one of four messages that varied in level of threat (high vs. low) and efficacy (high vs. low). Concomitantly, psychophysiological measures (heart rate and skin conductance) were registered. Perceived threat and efficacy varied according to the characteristics of the message. High-threat messages elicited significantly different levels of autonomic arousal than low-threat messages. Following of behavioral recommendation was higher among subjects who were exposed to the high threat / high efficacy stimulus, those who reported high perceived threat, and for those who showed an autonomic response pattern related to the facilitation of attentional processes. Résumé Les auto-évaluations et les réactions psychophysiologiques aux messages véhiculant des peurs Cette étude fut réalisée afin d'évaluer la relation entre les auto-évaluations et les réactions psychophysiologiques à des messages véhiculant des peurs ainsi que les changements suscités par ceux-ci. 92 sujets ont visionné un de quatre messages variant en niveau de danger (élevé ou faible) et d,efficacité (forte ou faible). En même temps, des mesures psychophysiologiques (le rythme cardiaque et la conduction cutanée) furent enregistrées. La perception de danger et d'efficacité variait suivant les caractéristiques du message. Les messages à danger élevé suscitaient des niveaux d,éveil autonome sensiblement différents des messages à faible danger. Le suivi de recommandations comportementales était plus élevé chez les sujets ayant été exposés au stimulus à danger élevé et à forte efficacité, chez ceux ayant déclaré une perception de danger élevé ainsi que chez ceux ayant présenté un schéma de réaction autonome liéà la facilitation des processus attentionnels. Abstract Selbstauskünfte zu und psychophysiologische Reaktionen auf Furchtappelle Ziel dieser Studie war es, die Beziehung zwischen den Aussagen zu und den psychophysiologischen Reaktionen auf Furchtappelle und Verhaltensänderungen zu untersuchen. 92 Teilnehmer sahen eine von vier Botschaften, die nach dem Grad der Gefahr (hoch vs. niedrig) und der Selbstwirksamkeit (hoch vs. niedrig) variierten. Begleitend wurden psychophysiologische Messungen (Herzfrequenz, Hautleitwiderstand) durchgeführt. Die wahrgenommene Bedrohung und Selbstwirksamkeit variierte nach den Charakteristika der Botschaft. Bei Botschaften mit hoher Gefahr zeigten die Teilnehmer einen anderen Grad an autonomer Erregung als bei Botschaften mit geringer Gefahr. Teilnehmer, die den Stimulus mit hoher Gefahr und hoher Selbstwirksamkeit rezipiert hatten, folgten den Verhaltensempfehlungen häufiger als diejenigen, die eine hohe wahrgenommene Gefahr berichteten und jene, die ein autonomes Reaktionsmuster zeigten, welches im Zusammenhang mit Zuwendung und Aufmerksamkeit steht. Resumen Los Auto-Reportes y las Respuestas Psico-Fisiológicas a las Apelaciones al Miedo Este estudio fue designado para evaluar la relación entre los auto-reportes y las respuestas psico-fisiológicas a las apelaciones al miedo y los cambios de comportamiento provocados por estos. 92 sujetos observaron 1 de 4 mensajes que variaron en su nivel de amenaza (alto o bajo) y la eficacia (alta o baja). Concomitantemente, las medidas psico-fisiológicas (pulso cardíaco y conductor de la piel) fueron registradas. La amenaza percibida y la eficacia variaron de acuerdo a las características del mensaje. Los mensajes de amenaza alta provocaron diferentes niveles significativos de excitación nerviosa que los mensajes de amenaza baja. Siguiendo la recomendación de comportamiento fue más alta entre los sujetos que fueron expuestos a la amenaza alta/ eficacia de estímulo alta, aquellos que reportaron una amenaza percibida alta, y para los que mostraron pautas de respuesta nerviosas relacionadas con la facilitación de los procesos de atención. ZhaiYao Yo yak [source] Cognitive-behavioral treatment for chronic nightmares in trauma-exposed persons: assessing physiological reactions to nightmare-related fearJOURNAL OF CLINICAL PSYCHOLOGY, Issue 4 2010Jamie L. Rhudy Abstract Cognitive-behavioral treatments (CBTs) that target nightmares are efficacious for ameliorating self-reported sleep problems and psychological distress. However, it is important to determine whether these treatments influence objective markers of nightmare-related fear, because fear and concomitant physiological responses could promote nightmare chronicity and sleep disturbance. This randomized, controlled study (N=40) assessed physiological (skin conductance, heart rate, facial electromyogram) and subjective (displeasure, fear, anger, sadness, arousal) reactions to personally relevant nightmare imagery intended to evoke nightmare-related fear. Physiological assessments were conducted at pretreatment as well as 1-week, 3-months, and 6-months posttreatment. Results of mixed effects analysis of variance models suggested treatment reduced physiological and subjective reactions to nightmare imagery, gains that were generally maintained at the 6-month follow-up. Potential implications are discussed. © 2010 Wiley Periodicals, Inc. J Clin Psychol 66: 1,18, 2010. [source] The influence of violent and nonviolent computer games on implicit measures of aggressivenessAGGRESSIVE BEHAVIOR, Issue 1 2010Matthias Bluemke Abstract We examined the causal relationship between playing violent video games and increases in aggressiveness by using implicit measures of aggressiveness, which have become important for accurately predicting impulsive behavioral tendencies. Ninety-six adults were randomly assigned to play one of three versions of a computer game that differed only with regard to game content (violent, peaceful, or abstract game), or to work on a reading task. In the games the environmental context, mouse gestures, and physiological arousal,as indicated by heart rate and skin conductance,were kept constant. In the violent game soldiers had to be shot, in the peaceful game sunflowers had to be watered, and the abstract game simply required clicking colored triangles. Five minutes of play did not alter trait aggressiveness, yet an Implicit Association Test detected a change in implicit aggressive self-concept. Playing a violent game produced a significant increase in implicit aggressive self-concept relative to playing a peaceful game. The well-controlled study closes a gap in the research on the causality of the link between violence exposure in computer games and aggressiveness with specific regard to implicit measures. We discuss the significance of importing recent social,cognitive theory into aggression research and stress the need for further development of aggression-related implicit measures. Aggr. Behav. 36:1,13, 2010. © 2009 Wiley-Liss, Inc. [source] Physiologic reactivity to startling tones in female vietnam nurse veterans with PTSDJOURNAL OF TRAUMATIC STRESS, Issue 5 2007Margaret A. Carson Posttraumatic stress disorder (PTSD) is associated with larger heart rate (HR), skin conductance (SC), and eyeblink responses to sudden, loud tones. The present study tested this association in female nurse veterans with PTSD related to witnessing patients' death, severe injury and/or suffering during their Vietnam service. Nurses with current, past but not current, or who never had PTSD listened to 15 consecutive 95-dB, 500-ms, 1000-Hz tones with sudden onsets, while HR, SC, and eyeblink responses were measured. Nurses with current PTSD produced significantly larger averaged HR, but not SC or eyeblink responses across tone trials. A larger HR response to loud tones is one of the most robust physiologic findings in PTSD and may reflect increased defensive responding. [source] Increases in core body temperature precede hot flashes in a prostate cancer patientPSYCHO-ONCOLOGY, Issue 5 2009Laura J. Hanisch Abstract Objective: An effective and safe alternative treatment to hormone replacement therapy for hot flashes is needed for cancer patients. Interventions targeting the triggering mechanisms of hot flashes hold promise. Increases in core body temperature are a precursor of most hot flashes in women, and similar findings in prostate cancer patients undergoing androgen deprivation therapy would support further research in this area. We present preliminary findings of physiological changes in a prostate cancer patient with frequent hot flashes. Methods: Physiological changes in sternal skin conductance, heart rate, and core body temperature were continuously measured during two 3.5,h laboratory sessions. Perceived characteristics of hot flashes were recorded in a diary. Results: Five hot flashes were reported during laboratory sessions. Severity and bother ratings were low. All hot flashes were accompanied by large increases in sternal skin conductance and moderate increases in heart rate. Core body temperature increased 0.11,0.32°C prior to and fell 0.23,0.44°C following the peak increase in skin conductance. Conclusions: This case study suggests that hot flashes in men may be preceded by increases in core body temperature. Identification of behavioral factors that raise core body temperature may lead to specific treatment strategies to reduce the frequency of hot flashes. Copyright © 2008 John Wiley & Sons, Ltd. [source] The effects of smoking on selective attention as measured by startle reflex, skin conductance, and heart rate responses to auditory startle stimuliPSYCHOPHYSIOLOGY, Issue 1 2010Justin E. Greenstein Abstract The present study examined the effects of cigarette smoking on attentional processing by measuring nondeprived smokers' (n=39), minimally deprived smokers' (n=36), and nonsmokers' (n=34) startle eyeblink reflex, heart rate, and skin conductance responses (SCR) to acoustic startle stimuli (105 dB) during directed attention tasks. Whereas smokers demonstrated smaller startle responses than nonsmokers during a directed attention visual task, no difference in startle response magnitude emerged between the two smoking groups, nor did we observe an effect of smoking on SCR or heart rate response to the startle stimuli. Our findings suggest that smokers differ from nonsmokers in their selective attention abilities and that smoking does not enhance minimally deprived smokers' selective attention. [source] Attenuation of positive and negative affect in men and women at increased risk for hypertension: A function of endogenous barostimulation?PSYCHOPHYSIOLOGY, Issue 1 2009Daniel Z. Wilkinson Abstract We hypothesized that activation of endogenous baroreflexes would be associated with reduced responsivity to affective stimuli and that this effect would be enhanced in individuals at risk for hypertension. Images from the International Affective Picture System were presented during systolic and diastolic phases of the cardiac cycle. Affective responsivity was measured using electromyographic activity, skin conductance, and ratings of arousal and valence. Compared to offspring of normotensives, individuals with a parental history of hypertension showed reduced responsivity to both positive and negative affective stimuli; however, responsivity did not differ as a function of cardiac cycle phase. Although these findings do not support a barostimulation mechanism of affective dampening, it is premature to discount the baroreflex inhibition hypothesis given the limited affective reactions elicited by visual stimuli presented in the laboratory. [source] Arousal and attention: Picture size and emotional reactionsPSYCHOPHYSIOLOGY, Issue 5 2007Maurizio Codispoti Abstract Building on the assumption that the motivational relevance of an emotional scene depends on contextual factors such as proximity or stimulus size, the present study examined the effects of picture size on emotional perception using autonomic, facial, and subjective reactions. Affective changes were measured while participants viewed pictures presented in small, medium, and large sizes and varying in affective picture content. Whereas affective modulation of heart rate and Corrugator Supercilii muscle activity were not modulated by picture size, emotional modulation of skin conductance was absent for the smallest stimuli and increased linearly for the medium and largest stimulus sizes. Stimulus size modulated sympathetic changes possibly related to activation of the strategic motivational systems and action preparation. In contrast, responses related to orienting, categorization, and communicative functions did not covary with picture size. [source] Validation of sternal skin conductance for detection of hot flashes in prostate cancer survivorsPSYCHOPHYSIOLOGY, Issue 2 2007Laura J. Hanisch Abstract The gold standard for objectively measuring hot flashes in women is an increased sternal skin conductance level (SCL), but validation studies in prostate cancer patients are lacking. In the laboratory, an SCL increase of ,1.78 micro-mho in 45 s had a sensitivity of 68% and a positive predictive value of 100% in detecting self-reported hot flashes among prostate cancer patients. Outside the laboratory, 71% of the objective markers of hot flashes were accompanied by a subjective report of a hot flash, and 65% of subjective reports occurred in the absence of an objective criterion. This study demonstrates that sternal skin conductance can be used to detect hot flashes in men in a manner analogous to its utilization among women. Such use would improve outcome analysis of treatment studies. [source] The psychophysiology of the maternal,fetal relationshipPSYCHOPHYSIOLOGY, Issue 4 2004Janet A. Dipietro Abstract 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. [source] An alternative to Unibase/glycol as an effective nonhydrating electrolyte medium for the measurement of electrodermal activityPSYCHOPHYSIOLOGY, Issue 4 2002Sharon L. Dormire Although Unibase cream has been an effective medium for electrodermal recordings, its production has recently been discontinued. This study compared alternative media to Unibase for effectiveness. Three base creams similar to Unibase were initially compared for in vitro viscosity and effectiveness. Based upon this analysis one cream was eliminated. A volunteer sample of 6 postmenopausal women with hot flashes and 6 young women without flashes was recruited. Media were evaluated for viscosity and effectiveness of skin conductance. Results indicated that one electrolyte media produced readings within the normal range, identified true positive hot flashes, and produced few false negative readings whereas the second produced largely unreadable results with many false negative hot flashes. An appropriate substitute for Unibase as an effective electrolyte medium for measurement of electrodermal activity was identified. [source] The Clitoral Photoplethysmograph: A New Way of Assessing Genital Arousal in WomenTHE JOURNAL OF SEXUAL MEDICINE, Issue 6 2009Jeroen Gerritsen MSc ABSTRACT Introduction., In the present study, we introduce clitoral photoplethysmography as an instrument to assess clitoral blood volume (CBV). In research on female sexual functioning, vaginal pulse amplitude (VPA), as measured using vaginal photoplethysmography, has been used extensively as a measure of vaginal vasocongestion. Measurement of clitoral blood flow has thus far been problematic, mainly because of methodological constraints. Aim., To demonstrate that CBV is a valuable, easy to use complementary measure for the female sexual response, offering additional information to the VPA. Methods., Thirty women with and without female sexual dysfunction (FSD) watched neutral and erotic film clips. At the end of the erotic clip, the session was interrupted to induce inhibition of the sexual response. Another neutral clip followed the interruption. VPA and CBV were measured simultaneously, as well as skin conductance levels (SCLs), to assess the amount of sympathetic activity. Main Outcome Measures., VPA, CBV, SCL. Results., For both FSD and non-FSD women, VPA and CBV increased when sexually explicit material was presented. Changes in skin conductance significantly predicted changes in CBV (b = ,0.61, t[27] = ,3.88, P < 0.001), but not in VPA. A large increase in sympathetic activity was accompanied by a large decrease in CBV. Furthermore, a large increase in CBV at the end of the erotic film clip presentation, as compared with the neutral clip, was accompanied by a relatively small increase in VPA (b = ,0.39, t[29] = ,2.25, P < 0.033). Conclusion., CBV is a valid and sensitive tool to measure the female genital response. In the present study, it was particularly useful in investigating sexual inhibition, when used in combination with SCL. Furthermore, high CBV appeared to inhibit VPA, suggesting that VPA reflects an automatic preparatory response rather than genital arousal per se. Gerritsen J, van der Made F, Bloemers J, van Ham D, Kleiverda G, Everaerd W, Olivier B, Levin R, and Tuiten A. The clitoral photoplethysmograph: A new way of assessing genital arousal in women. J Sex Med 2009;6:1678,1687. [source] Monitoring of intra-operative nociception: skin conductance and surgical stress index versus stress hormone plasma levelsANAESTHESIA, Issue 10 2010T. Ledowski Summary ,Surgical Stress Index' and the ,Number of Fluctuations in Skin Conductance.s,1, use different methods to analyse sympathetic tone and so provide an estimate of peri-operative analgesia. The aim of our study was to investigate the relationship between these methods and stress hormone plasma levels. In 20 patients scheduled for elective surgery, values of the two methods, mean arterial blood pressure, heart rate and blood samples (to measure plasma levels of adrenaline, noradrenaline, adrenocorticotrophic hormone and cortisol) were obtained at five time points. Changes in Surgical Stress Index and the Number of Fluctuations in Skin Conductance.s,1 only partially reflected changes in plasma noradrenaline levels. Surgical Stress Index, heart rate and blood pressure, but not the ,Number of Fluctuations in Skin Conductance.s,1 changed in response to changes in depth of analgesia by showing significant differences between before and after a bolus of fentanyl. However, the overall predictive ability of both methods was poor. [source] Monitoring of sympathetic tone to assess postoperative pain: skin conductance vs surgical stress indexANAESTHESIA, Issue 7 2009T. Ledowski Summary The number of fluctuations in skin conductance per second has been described as a potential tool for monitoring postoperative pain. More recently, the surgical stress index has shown promising correlations with intra-operative painful stimuli. We compared both methods for their ability to assess postoperative pain, in 100 postoperative patients who were also asked to quantify their level of pain at different time points in the recovery room. The number of fluctuations per second and surgical stress index were significantly different between pain scoring , 5/10 and > 5/10 on a numeric rating scale (mean (SE) number of fluctuations per second 0.12 (0.02) vs 0.21 (0.03), respectively; p = 0.017, and surgical stress index 57 (1.4) vs 64 (1.9) points, respectively; p = 0.001). Both number of fluctuations in skin conductance per second and surgical stress index identified timepoints with moderate to severe pain with only moderate sensitivity and specificity. [source] | ||||||||||||||||||||||||||||