The Influence of Virtual Forest Walk on Physiological and Psychological Responses

The authors of this paper sought to investigate the impact of virtual forest therapy based on realistic versus dreamlike environments on reducing stress levels. Today, people are facing an increase in stress levels in everyday life, which may be due to personal life, work environment, or urban area expansion. Previous studies have reported that urban environments demand more attention and mental workload than natural environments. However, evidence for the effects of natural environments as virtual forest therapy on stress levels has not yet been fully explored. In this study, a total of 20 healthy participants completed a letter-detection test to increase their stress level and were then randomly assigned to two different virtual environments representing realistic and dreamlike graphics. The participants’ stress levels were assessed using two physiological methods that measured heart rate and skin conductance levels and one psychological method through the Profile of Mood States (POMS) questionnaire. These indicators were analyzed using a sample t-test and a one-way analysis of variance. The results showed that virtual forest environments could have positive stress-relieving effects. However, realistic graphics were more efficient in reducing stress. These findings contribute to growing forest therapy concepts and provide new directions for future forest therapy research.

Electrochemical Skin Conductance Alterations during Spinal Cord Stimulation: An Experimental Study

Despite the well-known clinical effects of spinal cord stimulation (SCS), the mechanisms of action have not yet been fully unraveled. The primary aim of this study was to measure whether electrochemical skin conductance, as a measure of peripheral sympathetic autonomic function, is altered by SCS. A second aim was to compare skin conductance levels of patients with failed back surgery syndrome (FBSS) with age- and sex-matched healthy controls. Twenty-three patients with FBSS treated with SCS participated in this study. Sudomotor function was measured with the SudoscanTM instrument on the hands and feet during SCS on and off states. Difference scores in skin conductance between patients and age- and sex-matched healthy controls were calculated. Normal sudomotor function at the painful lower limb was revealed for 61% of the patients when SCS was activated. Skin conductance levels were not altered between on and off states of SCS. Differences in scores between patients and healthy controls were significantly different from zero. This study showed that SCS does not influencing the sympathetic nervous system in patients with FBSS, as measured by skin conductance levels. Moreover, it suggested that there is no normalization of the functioning of the sympathetic nervous system, despite the effectiveness of SCS to reduce pain intensity.

Using Ultrasonic Haptics Within an Immersive Spider Exposure Environment to Provide a Multi-Sensorial Experience

A proof of concept virtual reality system is presented that integrates ultrasonic feedback sensations to provide a demonstrative virtual reality exposure therapy environment containing multiple scenarios with virtual spiders. This system and environment were utilised to conduct a study containing 35 participants with the goal of investigating the effect the environment could have on their level of anxiety. This level of anxiety was measured in three different forms: changes in frontal asymmetry analysis of EEG data, changes in skin conductance levels and subjective units of distress. The Fear of Spiders Questionnaire was used to determine which participants in the study reported to be moderately afraid of spiders. For these participants all three measurement forms for anxiety showed statistically significant increases in a comparison between baseline and scenarios with the virtual spiders. A statistically significant correlation between scores on the Fear of Spiders Questionnaire and changes in anxiety shows the system to have had a greater effect on the anxiety levels of those who were more afraid of spiders, than those who were not. There was also a statistically significant correlation discovered between immersion and increase in anxiety, highlighting the significance of immersion in future virtual reality exposure therapy applications.

Your pleasure is mine; when people share a musical emotional experience during a live music performance in a concert hall

Over the years, several publications have proposed that musical sound could be an ancestral emotional way of communication, thus positing an ancestral biological function for music. Understanding how musical emotions, and the pleasure derived from music regardless of the musical valence, can be shared between individuals is a fascinating question, and investigating it can shed light on the function of musical reward. Is the pleasure felt at the individual level transmitted on a collective level? And if so, how? We investigated these questions in a natural setting during an international competition for orchestra conductors. Participants (n=15) used a dedicated smartphone app to report their subjective emotional experiences in real time during a concert. We recorded participant’s electrodermal activity (EDA) and cerebral activity with electroencephalography (EEG). The overall behavioral real time ratings suggest a possible social influence on the reported and felt pleasure. The physically closer the participants, the more similar their reported pleasure. We estimated the inter-individual cerebral coherence, which indicates the degree of mutual cerebral information between pairs of participants in the frequency domain. The results show that when people simultaneously reported either high or low pleasure, their cerebral activities were closer than for simultaneous neutral pleasure reports. Participants’ skin conductance levels were also more coupled when reporting higher emotional degrees simultaneously. More importantly, the participants who were physically closer had higher cerebral coherence, but only when they simultaneously reported intense pleasure. We propose that mechanisms of emotional contagion and/or emotional resonance could explain why a form of ‘emotional connecting force’ could arise between people.

The critical role of mental imagery in human emotion: insights from fear-based imagery and aphantasia

One proposed function of imagery is to make thoughts more emotionally evocative through sensory simulation, which can be helpful both in planning for future events and in remembering the past, but also a hindrance when thoughts become overwhelming and maladaptive, such as in anxiety disorders. Here, we report a novel test of this theory using a special population with no visual imagery: aphantasia. After using multi-method verification of aphantasia, we show that this condition, but not the general population, is associated with a flat-line physiological response (skin conductance levels) to reading and imagining frightening stories. Importantly, we show in a second experiment that this difference in physiological responses to fear-inducing stimuli is not found when perceptually viewing fearful images. These data demonstrate that the aphantasic individuals' lack of a physiological response when imaging scenarios is likely to be driven by their inability to visualize and is not due to a general emotional or physiological dampening. This work provides evidence that a lack of visual imagery results in a dampened emotional response when reading fearful scenarios, providing evidence for the emotional amplification theory of visual imagery.

The Arousal Effect of Exclusionary and Inclusionary Situations on Social Affiliation Motivation and Its Subsequent Influence on Prosocial Behavior

Given the negative costs of exclusion and the relevance of belongingness for humans, the experience of exclusion influences social affiliation motivation, which in turn is a relevant predictor of prosocial behavior. Skin conductance is a typical measure of the arousal elicited by emotions. Hence, we argued that both inclusion and exclusion will increase skin conductance level due to the increase of either positive affect or anger affects, respectively. Moreover, we argued that emotional arousal is also related to social affiliation motivation and prosocial behavior. A total of 48 students were randomly allocated to either an inclusionary or exclusionary condition and their skin conductance levels were recorded during an experiment in which they completed an online questionnaire and played the game “Cyberball.” Results indicated that (a) individuals who perceived high exclusion felt angrier than individuals perceiving high inclusion, who feel positive affect; (b) no differences were evidenced in terms of skin conductance between exclusion and inclusion situations; (c) over-aroused individuals were less motivated to affiliate; and (d) individuals with lower affiliation motivation behaved in a less prosocial way. The results were congruent to the argument that behaving prosocially may be a way to gain the desired affiliation.

Physiological synchrony is associated with cooperative success in real-life interactions

Cooperation is pivotal for society to flourish. To foster cooperation, humans express and read intentions via explicit signals and subtle reflections of arousal visible in the face. Evidence is accumulating that humans synchronize these nonverbal expressions and the physiological mechanisms underlying them, potentially influencing cooperation. The current study is designed to verify this putative linkage between synchrony and cooperation. To that end, 152 participants played the Prisoner’s Dilemma game in a dyadic interaction setting, sometimes facing each other and sometimes not. Results showed that synchrony in both heart rate and skin conductance level emerged during face-to-face contact. However, only synchrony in skin conductance levels predicted cooperative success of dyads. Crucially, this positive linkage was strengthened when participants could see each other. These findings show the strong relationship between our bodily responses and social behavior, and emphasize the importance of studying social processes between rather than within individuals in real-life interactions.

Moments that Matter? On the Complexity of using Triggers Based on Skin Conductance to Sample Arousing Events within an Experience Sampling Framework

To sample situations that are psychologically arousing in daily life, we implemented an experience sampling strategy in which 82 Dutch young adults ( Mage = 20.73) were triggered based on random time intervals and based on physiological skin conductance scores across a period of 5 days. When triggered, participants had to fill in short surveys on affect, situational characteristics and event characteristics on their smartphone. We found theoretically expected relationships between the skin conductance signal on the one hand and self–reported arousal and positive energy (e.g. energetic and enthusiastic) on the other hand, although effect sizes were small. Unexpectedly, none of the negative affective scales (i.e. irritation, anxiety, and negative valence) were predicted by skin conductance levels. Despite the (partial) validity of the signal, a simple algorithm that triggered the survey based on relative increases of skin conductance levels produced counterintuitive results due to a dependence between level and slope. Additional exploratory analyses highlighted other skin conductance signal characteristics (i.e. autocorrelation, number of peaks, and change points) that might be worth examining when designing future algorithms to sample arousing moments. Overall, our experiences highlight not only the promise but also the complexity of real–time measurement of physiological processes in daily life. © 2020 The Authors. European Journal of Personality published by John Wiley & Sons Ltd on behalf of European Association of Personality Psychology

A syncing feeling: Reductions in physiological arousal in response to observed social synchrony

Synchronized movements are often key elements in activities where social bonding and emotional connection are a shared goal, such as religious gatherings, sporting events, parties, and weddings. Previous studies have shown that synchronous movements enhance prosocial attitudes and affiliative behaviors. Similarly, observers attribute more social closeness to people moving synchronously together than people moving asynchronously. The mechanisms by which synchrony modulates these attributions are not well understood. In the present study, we ask whether viewing synchronous activities increases physiological arousal as measured by skin conductance, and whether group size impacts this effect. Undergraduates viewed a series of short videos depicting people moving either (1) in or out of synchrony with each other and (2) in a large or small group. Participants’ skin conductance was measured. Change in skin conductance levels and response counts were attenuated while watching synchronous movement, but only in the large-group condition. Post-hoc analyses suggest that viewer enjoyment/interest in the large-group synchronous videos mediated this association for phasic skin conductance responses, but no evidence of mediation was found for tonic skin conductance levels. Results extend previous research on affiliative effects of first-person interpersonal synchrony and demonstrate that watching others moving synchronously has an attenuating effect on observers’ physiological state.

Threat rapidly discrupts Reward Reversal Learning

Threat changes cognition to facilitate adaptive coping. However, when threat becomes overwhelming, this may be deleterious for mental health especially in vulnerable individuals. Flexible decision-making was probed with a reward reversal task to investigate, how well healthy participants (N=34) can adapt to changes in reward contingency when they expect adverse events (i.e. electric shocks). Relative to a safe control condition, threat-of-shock significantly impaired reward reversal learning. Moreover, enhanced self-reported threat ratings and elevated skin conductance levels support the successful induction of stressfull and aversive apprehensions. Findings are in line with existing literature showing stress-induced inhibition of goal-directed behavior, at advantage of a reflexive (habitual) response style. Notably, reversal learning was rapidly restored with the omission of threat through several cycles of threat and safety contexts within one experimental session. These results extend the current literature and illuminate the immediate consequence of a sustained threatening stressor (and its removal) on decision-making. Better knowledge of the immediate effects of anticipatory anxiety on behavior can improve understanding of psychopathology and may be informative for the development of effective therapy of anxiety and emotion dysregulation.