Engaging in Awkward Social Interactions in a Virtual Environment Designed for Exposure-Based Psychotherapy for People with Generalized Social Anxiety Disorder: An International Multisite Study.

The effectiveness of in virtuo exposure-based treatment of performance-only social anxiety disorder (SAD) has been demonstrated in several studies. However, few studies have validated virtual environments with participants suffering from generalized SAD. The goal of this study is to confirm the potential of a virtual environment in inducing anxiety in adults suffering from generalized SAD, compared to adults without SAD, when engaged in awkward social interactions. Differences between participants from two different countries were also explored. The sample consisted of 15 participants with SAD from Canada, 17 participants without SAD from Canada, 16 participants with SAD from Spain, and 21 participants without SAD from Spain. All participants were immersed in a control virtual environment and in an experimental virtual environment considered potentially anxiety-inducing for individuals with generalized SAD. As hypothesized, results showed that the experimental virtual environment induced a higher level of anxiety than the control environment among participants with SAD compared to those without SAD. The impact on anxiety of each socially threatening task performed during the experimental immersion was statistically significant. In terms of anxiety responses, no significant differences were found between participants from Canada and Spain. However, spatial presence and ecological validity were higher in Canadians than in Spaniards. Unwanted negative side effects induced by immersions in virtual reality were higher in the SAD group. This study highlights the importance for therapists to engage people with SAD in clinically relevant tasks while immersed in VR psychotherapeutic applications.

Development and Testing of a Portable Virtual Reality-Based Mirror Visual Feedback System with Behavioral Measures Monitoring.

Virtual Reality (VR) is a technology that has been used to provide the Mirror Visual Feedback (MVF) illusion to patients with promising results. In the present work, the goal is to design, develop and test a portable VR-based MVF system that monitors behavioral information about the performance of a simple motor task. The developed application runs in a stand-alone VR system and allows the researcher to select the real and virtual hands used to perform the motor task. The system was evaluated with a group of twenty healthy volunteers (12 men and 8 women) with ages between 18 and 66 years. Participants had to repetitively perform a motor task in four different experimental conditions: two mirror conditions (performing real movements with the dominant and with the non-dominant hand) and two non-mirror conditions. A significant effect of the experimental condition on embodiment score (p < 0.001), response time (p < 0.001), performance time (p < 0.001), trajectory length (p < 0.004) and trajectory maximum horizontal deviation (p < 0.001) was observed. Furthermore, a significant effect of the experimental moment (initial, middle and final parts of the training) on the performance time was observed (p < 0.001). These results show that the monitored parameters provide relevant information to evaluate the participant's task performance in different experimental conditions.

Power Spectral Density and Functional Connectivity Changes due to a Sensorimotor Neurofeedback Training: A Preliminary Study.

Neurofeedback is a form of neuromodulation based on learning to modify some aspects of cortical activity. Sensorimotor rhythm (SMR) oscillation is one of the most used frequency bands in neurofeedback. Several studies have shown that subjects can learn to modulate SMR power to control output devices, but little is known about possible related changes in brain networks. The aim of this study was to investigate the enhanced performance and changes in EEG power spectral density at somatosensory cerebral areas due to a bidirectional modulation-based SMR neurofeedback training. Furthermore, we also analyzed the functional changes in somatosensory areas during resting state induced by the training as exploratory procedure. A six-session neurofeedback protocol based on learning to synchronize and desynchronize (modulate) the SMR was implemented. Moreover, half of the participants were enrolled in two functional magnetic resonance imaging resting-state sessions (before and after the training). At the end of the training, participants showed a successful performance enhancement, an increase in SMR power specific to somatosensory locations, and higher functional connectivity between areas associated with somatosensory activity in resting state. Our research increases the better understanding of the relation between EEG neuromodulation and functional changes and the use of SMR training in clinical practice.

The Relationship Between Heart Rate Variability and Electroencephalography Functional Connectivity Variability Is Associated With Cognitive Flexibility.

The neurovisceral integration model proposes a neuronal network that is related to heart rate activity and cognitive performance. The aim of this study was to determine whether heart rate variability (HRV) and variability in electroencephalographic (EEG) functional connectivity in the resting state are related to cognitive flexibility. Thirty-eight right-handed students completed the CAMBIOS test, and their heart and EEG activity was recorded during 6 min in the resting state with their eyes open. We calculated correlations, partial correlations and multiple linear regressions among HRV indices, functional brain connectivity variability and CAMBIOS scores. Furthermore, the sample was divided into groups according to CAMBIOS performance, and one-way ANOVA was applied to evaluate group differences. Our results show direct and inverse correlations among cognitive flexibility, connectivity (positive and negative task networks) and heartbeat variability. Partial correlations and multiple linear regressions suggest that the relation between HRV and CAMBIOS performance is mediated by neuronal oscillations. ANOVA confirms that HRV and variability in functional brain connectivity is related to cognitive performance. In conclusion, the levels of brain signal variability might predict cognitive flexibility in a cognitive task, while HRV might predict cognitive flexibility only when it is mediated by neuronal oscillations.

Design and Validation of an FPGA-Based Configurable Transcranial Doppler Neurofeedback System for Chronic Pain Patients.

Neurofeedback is a self-regulation technique that can be applied to learn to voluntarily control cerebral activity in specific brain regions. In this work, a Transcranial Doppler-based configurable neurofeedback system is proposed and described. The hardware configuration is based on the Red Pitaya board, which gives great flexibility and processing power to the system. The parameter to be trained can be selected between several temporal, spectral, or complexity features from the cerebral blood flow velocity signal in different vessels. As previous studies have found alterations in these parameters in chronic pain patients, the system could be applied to help them to voluntarily control these parameters. Two protocols based on different temporal lengths of the training periods have been proposed and tested with six healthy subjects that were randomly assigned to one of the protocols at the beginning of the procedure. For the purposes of the testing, the trained parameter was the mean cerebral blood flow velocity in the aggregated data from the two anterior cerebral arteries. Results show that, using the proposed neurofeedback system, the two groups of healthy volunteers can learn to self-regulate a parameter from their brain activity in a reduced number of training sessions.

Altered cerebral blood flow velocity features in fibromyalgia patients in resting-state conditions.

The aim of this study is to characterize in resting-state conditions the cerebral blood flow velocity (CBFV) signals of fibromyalgia patients. The anterior and middle cerebral arteries of both hemispheres from 15 women with fibromyalgia and 15 healthy women were monitored using Transcranial Doppler (TCD) during a 5-minute eyes-closed resting period. Several signal processing methods based on time, information theory, frequency and time-frequency analyses were used in order to extract different features to characterize the CBFV signals in the different vessels. Main results indicated that, in comparison with control subjects, fibromyalgia patients showed a higher complexity of the envelope CBFV and a different distribution of the power spectral density. In addition, it has been observed that complexity and spectral features show correlations with clinical pain parameters and emotional factors. The characterization features were used in a lineal model to discriminate between fibromyalgia patients and healthy controls, providing a high accuracy. These findings indicate that CBFV signals, specifically their complexity and spectral characteristics, contain information that may be relevant for the assessment of fibromyalgia patients in resting-state conditions.

Rats with minimal hepatic encephalopathy show reduced cGMP-dependent protein kinase activity in hypothalamus correlating with circadian rhythms alterations.

Patients with liver cirrhosis show disturbances in sleep and in its circadian rhythms which are an early sign of minimal hepatic encephalopathy (MHE). The mechanisms of these disturbances are poorly understood. Rats with porta-caval shunt (PCS), a model of MHE, show sleep disturbances reproducing those of cirrhotic patients. The aims of this work were to characterize the alterations in circadian rhythms in PCS rats and analyze the underlying mechanisms. To reach these aims, we analyzed in control and PCS rats: (a) daily rhythms of spontaneous and rewarding activity and of temperature, (b) timing of the onset of activity following turning-off the light, (c) synchronization to light after a phase advance and (d) the molecular mechanisms contributing to these alterations in circadian rhythms. PCS rats show altered circadian rhythms of spontaneous and rewarding activities (wheel running). PCS rats show more rest bouts during the active phase, more errors in the onset of motor activity and need less time to re-synchronize after a phase advance than control rats. Circadian rhythm of body temperature is also slightly altered in PCS rats. The internal period length (tau) of circadian rhythm of motor activity is longer in PCS rats. We analyzed some mechanisms by which hypothalamus modulate circadian rhythms. PCS rats show increased content of cGMP in hypothalamus while the activity of cGMP-dependent protein kinase was reduced by 41% compared to control rats. Altered cGMP-PKG pathway in hypothalamus would contribute to altered circadian rhythms and synchronization to light.

A functional magnetic resonance imaging assessment of small animals' phobia using virtual reality as a stimulus.

BACKGROUND: To date, still images or videos of real animals have been used in functional magnetic resonance imaging protocols to evaluate the brain activations associated with small animals' phobia. OBJECTIVE: The objective of our study was to evaluate the brain activations associated with small animals' phobia through the use of virtual environments. This context will have the added benefit of allowing the subject to move and interact with the environment, giving the subject the illusion of being there. METHODS: We have analyzed the brain activation in a group of phobic people while they navigated in a virtual environment that included the small animals that were the object of their phobia. RESULTS: We have found brain activation mainly in the left occipital inferior lobe (P<.05 corrected, cluster size=36), related to the enhanced visual attention to the phobic stimuli; and in the superior frontal gyrus (P<.005 uncorrected, cluster size=13), which is an area that has been previously related to the feeling of self-awareness. CONCLUSIONS: In our opinion, these results demonstrate that virtual stimulus can enhance brain activations consistent with previous studies with still images, but in an environment closer to the real situation the subject would face in their daily lives.

Validation of a low-cost EEG device for mood induction studies.

New electroencephalography (EEG) devices, more portable and cheaper, are appearing on the market. Studying the reliability of these EEG devices for emotional studies would be interesting, as these devices could be more economical and compatible with Virtual Reality (VR) settings. Therefore, the aim in this work was to validate a low-cost EEG device (Emotiv Epoc) to monitor brain activity during a positive emotional induction procedure. Emotional pictures (IAPS) were used to induce a positive mood in sixteen participants. Changes in the brain activity of subjects were compared between positive induction and neutral conditions. Obtained results were in accordance with previous scientific literature regarding frontal EEG asymmetry, which supports the possibility of using this low-cost EEG device in future mood induction studies combined with VR.

Evaluating virtual reality mood induction procedures with portable EEG devices.

Virtual Environments (VEs) have been used as mood induction procedures. In this context, it is necessary to have instruments to analyze the emotional state during VE exposure. Objective techniques such as EEG should be evaluated for this purpose. The aim in this work was to study the changes in the brain activity with a portable EEG device during a negative mood induction based on a VE. A virtual park was used to induce a negative mood (sadness) in ten participants. Changes in the brain activity of subjects were compared between two moments (before and after emotional induction). Obtained results were in accordance with previous scientific literature regarding frontal EEG asymmetry, which supports the possibility of using the portable EEG as a reliable instrument to measure emotions in VE.

Measuring presence during the navigation in a virtual environment using EEG.

In the Virtual Reality field, presence refers to the sense of "being there" in the virtual world. Our aim in this work is to evaluate the usefulness of the Emotiv EPOC EEG device to measure the brain activations due to the sense of presence during the navigation in a Virtual Environment (VE), using for the analysis the sLORETA tool. We compare between two experimental conditions: free and automatic navigation through a VE. In this preliminary step, we monitored 9 healthy subjects, obtaining significant differences between the free and automatic navigation conditions in the activity of the right insula for the Theta and Alpha bands. The insula activation is related to stimulus attention and selfawareness processes, directly related with the sense of presence.

Reliability and validity of TIPS wireless ECG prototypes.

The aims of the present study are to examine the reliability and validity of the Heart Rate signal registered using two self-made wireless ECG systems, R-Tips and TipsShirt, and to compare them with another commercial ECG device typically used in psychophysiology studies. An ECG simulator was used to artificially generate signals corresponding to different cardiac frequencies. Results of the reliability study showed that the signal acquisition, signal processing and signal transmission were reliable and valid for R-Tips and TipsShirt. Consequently, these wireless ECG prototypes could be used for studies where the freedom of movements of the participants is fundamental without any loss of quality in the registered signals.

Using portable EEG devices to evaluate emotional regulation strategies during Virtual Reality exposure.

As Virtual Reality (VR) is starting to be used to train emotional regulation strategies, it would be interesting to propose objective techniques to monitor the emotional reactions of participants during the virtual experience. In this work, the main goal is to analyze if portable EEG systems are adequate to monitor brain activity changes caused by the emotional regulation strategies applied by the participants. The EEG signals captured from subjects that navigate through a virtual environment designed to induce a negative mood will be compared between three experimental groups that will receive different instructions about the emotional regulation strategies to apply. The study will allow us to validate the possibilities of portable EEG devices to monitor emotional regulation strategies during VR exposure.

Virtual representations of the self: engaging teenagers in emotional regulation strategies learning.

The aim of this paper is to present digital representations of humans (i.e., avatars) that look like the self, applied to the Mental Health (MH) field. Virtual Representations of the Self (VRS) are in our opinion a tool with a great potential for engaging teenagers in emotional regulation strategies learning and an excellent example of new technology application to the basic concept in psychology field such as Bandura's modeling [1]. VRSs have already demonstrated their potential on human behavior modification (e.g. modification of physical activity; eating habits) in general population [2]. Thus, the same technology can bring in our opinion a lot to the Mental Health field, especially in emotional regulation learning. This paper presents a theoretical background and describes the methodology that we plan to apply in order to validate the efficacy of VRSs in clinical settings. Also, the implications of such technology and future research lines are discussed.

GameTeen: new tools for evaluating and training emotional regulation strategies.

The aim of this paper is to describe GameTeen, a novel instrument for the assessment and training of Emotional Regulation (ER) strategies in adolescent population. These new tools are based on the use of 3D serious games that can be played under different settings. The evolution of ER strategies will be monitored in two ways depending on the setting where the tool is presented. Firstly, in the laboratory, physiological signals and facial expressions of participants will be recorded. Secondly, in real life settings, ecological momentary assessment tools will be used to obtain answers from the subjects using their mobile phone. The goal is to obtain more attractive and reliable tools to evaluate and train ER strategies.

Immersive virtual environments for emotional engineering: description and preliminary results.

This work aims to identify the arousal and presence level during an emotional engineering study. During the experimental sessions, a high-immersion Virtual Reality (VR) system, a CAVE-like configuration, will be used. Thirty-six volunteers will navigate through virtual houses that can be customized and that have been designed for emotional induction. Emotional induction will be obtained by stimulating the senses of sight, hearing and smell. For this purpose, the ambient lighting, music and smell will be controlled by the researcher, who will create a comfortable environment for the subject. Several physiological variables - Electrocardiogram (ECG), Respiratory signal and Galvanic Skin Response (GSR) - will be recorded during the sessions. The obtained results will help furniture companies identify the senses that have more influence on emotions and will be the basis for new studies about user needs in the sector of furniture and interior decoration.

Analysis of visual perception aspects of the virtual reality experience with transcranial Doppler monitoring.

Transcranial Doppler is a tool to measure blood flow velocity (BFV) in the main arteries of the brain that has been used in previous studies to analyze brain activity during virtual reality (VR) experiences. Increments in BFV were found during the exposure to virtual environments in comparison with baseline periods. However, due to the complexity of VR experiences, there are several factors that can be having an influence in these variations, so it is necessary to separately analyze those different aspects. In this work, we summarize our results related to visual perception. A method based on spectral analysis was used to analyze the magnitude and temporal evolution of the maximum BFV signal. Results showed that, in the presence of visual stimuli, BFV quickly rises to a maximum that is achieved after a few seconds. The contribution of the visual stimuli factor to the observed BFV variations during a VR experience can be estimated from the results of the developed work.

Contributions of functional magnetic resonance in the field of psychological treatments with virtual reality.

Many studies have been developed using brain imaging methods to investigate psychological disorders. On the other hand, there are many studies that make use of virtual reality (VR) to simulate a real condition during psychological treatments. In this research, we plan to analyze brain activity during the exposure to a virtual environment related to phobias. Our first goal is to study the possibility of activating brain areas related to phobias, specifically phobias to small animals (spiders and cockroaches), using virtual reality as stimulus, while the patient is inside a functional magnetic resonance imaging (fMRI) machine. The second goal of the research is to analyze if there are differences in the activated areas after patients have followed a psychological treatment for this specific phobia. That is why two different sessions with fMRI will be performed, before and after an intensive treatment for the phobia. In the fMRI room, participants will wear special glasses to visualize the VR environments in which they have to navigate (using also a joystick adapted to fMRI). They will have to perform some tasks while being exposed to the phobic stimuli. The VR environment used in the fMRI sessions has three different conditions: first, a clean room without spiders or cockroaches; second, the same room, but dirty and disordered (giving the sensation of having small animals, although actually there are none); third, the same dirty room but having spiders and cockroaches. It is our hypothesis that the patients will get anxious in the situation in which it is possible that the animal appears and the patterns of brain activation will be different in this condition.

A new visually evoked cerebral blood flow response analysis using a low-frequency estimation.

Transcranial Doppler (TCD) has been widely used to monitor cerebral blood flow velocity (BFV) during the performance of cognitive tasks compared with repose periods. Although one of its main advantages is its high temporal resolution, only some of the previous functional TCD studies have focused on the analysis of the temporal evolution of the BFV signal and none of them has performed a spectral analysis of the signal. In this study, maximum BFV data in both posterior cerebral arteries was monitored during a visual perception task (10 cycles of alternating darkness and illumination) for 23 subjects. A peak was located in the low-frequency band of the spectrum of the maximum BFV of each subject both during visual stimulation and repose periods. The frequency of this peak was in the range between 0.037 and 0.098Hz, depending on the subject, the vessel and the experimental condition. The component of the signal at this frequency, which is associated with the slow variations caused by the visual stimuli, was estimated. That way, the variations in BFV caused by the experimental stimuli were isolated from the variations caused by other factors. This low-frequency estimation signal was used to obtain parameters about the temporal evolution and the magnitude variations of the BFV in a reliable way, thus, characterizing the neurovascular coupling of the participants.