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.

Electrodermal Orienting Response During Active-Alert Hypnosis: Do Verbal Suggestions Influence Automatic Attentional Processes?

This study explored the influence of suggestions on differences in electrodermal laterality of the skin conductance orienting response (SCR). Thirty-two participants were randomly assigned to either permitting or excluding suggestions. During the dream task in the permitting condition the suggestion was: "You are aware of your surroundings and any distractions that might disturb your dream," while in the excluding condition the wording was: "No outside stimulus will disturb your sleep." Participants were presented with 12 standards and 2 deviant computer-generated tones during active-alert hypnosis and musical control conditions in a mixed within-between design. High hypnotizables produced higher SCRs after permissive compared to excluding suggestions during hypnosis, while low hypnotizables did the same in the control condition. Study limitations include some loss of data due to equipment failure and relative homogeneity of sample, therefore results cannot be considered definitive.

Altered States of Consciousness during Exercise, Active-Alert Hypnosis, and Everyday Waking State.

This retrospective study was a nonrandomized comparison of exercisers' (runners and participants of a spinning class) states of consciousness with subjects of active-alert hypnosis (AAH) and students in a class (control). Three hundred and seventy-five participants completed the Phenomenology of Consciousness Inventory (PCI). Runners, spinners, and participants of AAH scored higher on the altered experience and altered state of awareness dimensions of the PCI than the control group. Runners scored higher than participants of AAH and the control condition on the rationality dimension, and spinners scored higher than participants in the AAH condition. The AAH group scored lowest on the self-awareness dimension. On the volitional control dimension, the spinning and control groups scored significantly higher than the runner and AAH groups. The results suggest that exercise may lead to states of consciousness similar to AAH and thus increase responsiveness to a coach's training suggestions.

Phenomenological Experiences during Active-Alert Hypnosis: Comparison of Hypnotist and Subject.

There has been increasing clinical interest in active-alert hypnosis (AAH). However, relatively few studies have been devoted to studying its properties systematically. The present study compared the subjective experiences of subjects (31) and hypnotists (5) during AAH, using Pekala's Phenomenology of Consciousness Inventory (PCI), the Dyadic Interactional Harmony (DIH) scale and the Archaic Involvement Measure (AIM). Results demonstrated similarities between the experiences of subjects and hypnotists. The only significant difference between the subjects' and the hypnotists' experiences was shown by the PCI, which highlighted the differences stemming from the different roles of hypnotist and subject during the AAH. The study suggests it may be important to examine subjective descriptors in the exploration of personal experiences in studies of AAH.

Bilateral comparison of traditional and alternate electrodermal measurement sites.

Advances in mobile and wireless technology have expanded the scope of electrodermal research. Since traditional electrodermal measurement sites are not always suitable for laboratory research and are rarely appropriate for ambulatory measurements, there is a need to explore and contrast alternate measurement locations. We evaluated bilateral electrodermal activity (EDA) from five measurement sites (fingers, feet, wrists, shoulders, and calves). In a counterbalanced, randomized, within-subjects design study, participants (N = 115) engaged in a 4-min-long breathing exercise and were exposed to emotionally laden and neutral stimuli. High within-subject correlations were found between the EDA measured from fingers bilaterally (r = .89), between the left fingers and both feet (r = .72). Moderate correlations were found between EDA measured from the left fingers and wrists (r = .30 and r = .33), low correlations between the left fingers and the shoulders (r = -.03 and r = -.06) or calves (r = .05 and r = .14). Response latency was the shortest on the fingers while it was the longest on the lower body. Short response windows would miss some of the responses from the palmar surfaces and a substantial number from other evaluated locations. The fingers and the feet are the most reliable locations to measure from, followed by the wrists. We suggest setting site-specific response windows for different measurement locations. An investigation of repeatability showed that within-subject correlations, response frequencies, response amplitudes show a similar pattern from the first measurement time to a later one.

Obimon: An open-source device enabling group measurement of electrodermal activity.

Electrodermal activity (EDA) provides the means to gauge the activity of the sympathetic nervous system. Assessment of EDA for research purposes requires measurement systems that are sensitive to small changes in arousal in the full measurement range, collecting, storing, and monitoring data. The objective behind designing a new open-source device was to be able to measure EDA simultaneously on many subjects, monitoring their activity in real time remotely and collecting high precision data suitable for analyses. To assure feasibility of simultaneous measurements on multiple subjects, the devices must be compact and wearable, without compromising data quality. Experiments were carried out using synchronized devices in group and single subject environments. Validity of EDA measurements of Obimon was demonstrated compared to a reference system (Nexus) during a breathing exercise, a short movie, and while exposed to loud computer-generated tones, using Pearson correlation, Passing-Bablok regression, and Bland-Altman analysis. Seamless management of several Obimons and real-time visualization of EDA via Android phone/tablet application from a large number of participants was demonstrated. Based on analyses of the data collected, we conclude that the Obimon device presented here is a valid and feasible tool for collecting EDA in single or multisubject environments.

BILATERAL ELECTRODERMAL ACTIVITY IN THE ACTIVE-ALERT HYPNOTIC INDUCTION.

Shifts in hemispheric dominance were previously proposed to play a role in hypnosis. Participants (N = 32) were exposed to an active-alert hypnosis induction and a music-control condition while electrodermal activity was registered bilaterally, providing information on alterations in hemispheric dominance. The results suggest that highly hypnotizable participants show a shift to right-sided and low hypnotizable participants demonstrated a shift to left-sided electrodermal dominance in response to the induction, whereas no change in laterality is present in the control condition. Additionally, the authors found that self-reported hypnosis experiences were also associated with a shift in laterality. These results underline the importance of the shift to right hemispheric activity in hypnosis and underscore the importance of hemispheric changes in shaping subjective experience.

CHANGES IN OXYTOCIN AND CORTISOL IN ACTIVE-ALERT HYPNOSIS: Hormonal Changes Benefiting Low Hypnotizable Participants.

It is increasingly clear that oxytocin and cortisol play an intricate role in the regulation of behavior and emotions impacting health, relationships, and well-being. Their long-term, cross-generational effect makes them an important focus of the present study. This exploratory research examined changes in oxytocin and cortisol levels and their correlations with different phenomenological measures in both hypnotist and subject during active-alert hypnosis. The level of oxytocin increased whereas the level of cortisol decreased in the hypnotist. When comparing the oxytocin changes of subjects with their hypnotizability, those with low hypnotizability scores experienced an increase in oxytocin, and those with medium and high hypnotizability scores showed no change or decrease. This could explain why clients' hypnotizability is not considered an important factor during hypnotherapy.