What Is Medical Extended Reality? A Taxonomy Defining the Current Breadth and Depth of an Evolving Field.

Medical extended reality (MXR) has emerged as a dynamic field at the intersection of health care and immersive technology, encompassing virtual, augmented, and mixed reality applications across a wide range of medical disciplines. Despite its rapid growth and recognition by regulatory bodies, the field lacks a standardized taxonomy to categorize its diverse research and applications. This American Medical Extended Reality Association guideline, authored by the editorial board of the Journal of Medical Extended Reality, introduces a comprehensive taxonomy for MXR, developed through a multidisciplinary and international collaboration of experts. The guideline seeks to standardize terminology, categorize existing work, and provide a structured framework for future research and development in MXR. An international and multidisciplinary panel of experts was convened, selected based on publication track record, contributions to MXR, and other objective measures. Through an iterative process, the panel identified primary and secondary topics in MXR. These topics were refined over several rounds of review, leading to the final taxonomy. The taxonomy comprises 13 primary topics that jointly expand into 180 secondary topics, demonstrating the field's breadth and depth. At the core of the taxonomy are five overarching domains: (1) technological integration and innovation; (2) design, development, and deployment; (3) clinical and therapeutic applications; (4) education, training, and communication; and (5) ethical, regulatory, and socioeconomic considerations. The developed taxonomy offers a framework for categorizing the diverse research and applications within MXR. It may serve as a foundational tool for researchers, clinicians, funders, academic publishers, and regulators, facilitating clearer communication and categorization in this rapidly evolving field. As MXR continues to grow, this taxonomy will be instrumental in guiding its development and ensuring a cohesive understanding of its multifaceted nature.

Feasibility of combining spatial computing and AI for mental health support in anxiety and depression.

The increasing need for mental health support and a shortage of therapists have led to the development of the eXtended-reality Artificial Intelligence Assistant (XAIA). This platform combines spatial computing, virtual reality (VR), and artificial intelligence (AI) to provide immersive mental health support. Utilizing GPT-4 for AI-driven therapy, XAIA engaged participants with mild-to-moderate anxiety or depression in biophilic VR environments. Speaking with an AI therapy avatar in VR was considered acceptable, helpful, and safe, with participants observed to engage genuinely with the program. However, some still favored human interaction and identified shortcomings with using a digital VR therapist. The study provides initial evidence of the acceptability and safety of AI psychotherapy via spatial computing, warranting further research on technical enhancements and clinical impact.

ChatGPT's ability to comprehend and answer cirrhosis related questions in Arabic.

BACKGROUND AND STUDY AIMS: Cirrhosis is a chronic progressive disease which requires complex care. Its incidence is rising in the Arab countries making it the 7th leading cause of death in the Arab League in 2010. ChatGPT is a large language model with a growing body of literature demonstrating its ability to answer clinical questions. We examined ChatGPT's accuracy in responding to cirrhosis related questions in Arabic and compared its performance to English. MATERIALS AND METHODS: ChatGPTs responses to 91 questions in Arabic and English were graded by a transplant hepatologist fluent in both languages. Accuracy of responses was assessed using the scale: 1. Comprehensive, 2. Correct but inadequate, 3. Mixed with correct and incorrect/outdated data, and 4. Completely incorrect.Accuracy of Arabic compared to English responses was assessed using the scale: 1. Arabic response is more accurate, 2. Similar accuracy, 3. Arabic response is less accurate. RESULTS: The model provided 22 (24.2%) comprehensive, 44 (48.4%) correct but inadequate, 13 (14.3%) mixed with correct and incorrect/outdated data and 12 (13.2%) completely incorrect Arabic responses. When comparing the accuracy of Arabic and English responses, 9 (9.9%) of the Arabic responses were graded as more accurate, 52 (57.1%) similar in accuracy and 30 (33.0%) as less accurate compared to English. CONCLUSION: ChatGPT has the potential to serve as an adjunct source of information for Arabic speaking patients with cirrhosis. The model provided correct responses in Arabic to 72.5% of questions, although its performance in Arabic was less accurate than in English. The model produced completely incorrect responses to 13.2% of questions, reinforcing its potential role as an adjunct and not replacement of care by licensed healthcare professionals. Future studies to refine this technology are needed to help Arabic speaking patients with cirrhosis across the globe understand their disease and improve their outcomes.

Recording neural reward signals in the real-world using mobile-EEG and augmented reality.

The electrophysiological response to rewards recorded during laboratory-based tasks has been well documented over the past two decades, yet little is known about the neural response patterns in 'real-world' settings. To address this issue, we combined a mobile-EEG system with an augmented reality headset (which blends high definition "holograms" within the real-world) to record event-related brain potentials (ERP) while participants navigated an operant chamber to find rewards. 25 participants (age = 18-43, Male=6, Female=19) were asked to choose between two floating holograms marking a west or east goal-location in a large room, and once participants reached the goal location, the hologram would turn into a reward (5 cents) or no-reward (0 cents) cue. Following the feedback cue, participants were required to return to a hologram marking the start location, and once standing in it, a 3 second counter hologram would initiate the next trial. This sequence was repeated until participants completed 200 trials. Consistent with previous research, reward feedback evoked the reward positivity, an ERP component believed to index the sensitivity of the anterior cingulate cortex to reward prediction error signals. The reward positivity peaked around 235ms post-feedback with a maximal at channel FCz (M=-2.60µV, SD=1.73µV) and was significantly different than zero (p < 0.01). At a behavioral level, participants took approximately 3.38 seconds to reach the goal-location and exhibited a general lose-shift (68.3% ± 3.5) response strategy and were slightly slower to return to the start location following negative feedback (2.43 sec) compared to positive feedback (2.38 sec), evidence of post-error slowing. Overall, these findings provide the first evidence that combining mobile-EEG with augmented reality technology is a feasible solution to enhance the ecological validity of human electrophysiological studies of goal-directed behavior and a step towards a new era of human cognitive neuroscience research that blurs the line between laboratory and reality.

Virtual reality in the management of stress and anxiety disorders: A retrospective analysis of 61 people treated in the metaverse.

Mental health is the second largest group of health disorders associated with prolonged disability. Treating conditions such as stress and anxiety are a global health challenge due to inadequate funding and resources. Therefore, providing virtual treatment in the metaverse may provide a novel method of treatment for these conditions. We conducted a retrospective analysis of health records of people experiencing stress and anxiety who were treated principally in the metaverse using virtual reality. The main objective was to determine if virtual mental health treatment was achievable and safe, with measurable outcomes repeated at multiple time points. Here, 61 participants health records were evaluated (50% were female, 19% male, 31% identified as other). The cohort was 45.7 ± 15.7 years of age and reported no adverse effects with outcomes measured. Specifically, anxiety (via Generalized Anxiety Disorder Scale) decreased by 34% (p = 0.002) and stress (via Perceived Stress Scale) decreased by 32% (p < 0.001) after virtual intervention. The data suggests that this method of treatment was feasible, safe, and outcomes were obtainable over a range of time points. This early data suggest that management in the metaverse for these conditions may be beneficial, however, further prospective studies are necessary to better understand these clinical findings.

Virtual reality in the management of patients with low back and neck pain: a retrospective analysis of 82 people treated solely in the metaverse.

BACKGROUND: Clinically, neck pain disorders (NPD) and non-specific low back pain (NS-LBP) are respectively the fourth and first most common conditions associated with the greatest number of years lived with disability. Remote delivery of care may benefit healthcare sustainability, reduce environmental pollution, and free up space for those requiring care non-virtual care. METHODS: A retrospective analysis was performed on 82 participants with NS-LBP and/or NPD who received exercise therapy delivered solely in the metaverse using virtually reality. The study was to determine if this was achievable, safe, had appropriate outcome measures that could be collected, and if there was any early evidence of beneficial effects. RESULTS: The study demonstrated that virtual reality treatment delivered via the metaverse appears to be safe (no adverse events or side effects). Data for more than 40 outcome measures were collected. Disability from NS-LBP was significantly reduced (Modified Oswestry Low Back Pain Disability Index) by 17.8% (p < 0.001) and from NPD (Neck Disability Index) by 23.2% (p = 0.02). CONCLUSIONS: The data suggest that this method of providing exercise therapy was feasible, and safe (no adverse events reported), that complete reports were obtained from a large selection of patients, and that software acquired outcomes were obtainable over a range of time points. Further prospective research is necessary to better understand our clinical findings.

Assessing the Accuracy of Responses by the Language Model ChatGPT to Questions Regarding Bariatric Surgery.

PURPOSE: ChatGPT is a large language model trained on a large dataset covering a broad range of topics, including the medical literature. We aim to examine its accuracy and reproducibility in answering patient questions regarding bariatric surgery. MATERIALS AND METHODS: Questions were gathered from nationally regarded professional societies and health institutions as well as Facebook support groups. Board-certified bariatric surgeons graded the accuracy and reproducibility of responses. The grading scale included the following: (1) comprehensive, (2) correct but inadequate, (3) some correct and some incorrect, and (4) completely incorrect. Reproducibility was determined by asking the model each question twice and examining difference in grading category between the two responses. RESULTS: In total, 151 questions related to bariatric surgery were included. The model provided "comprehensive" responses to 131/151 (86.8%) of questions. When examined by category, the model provided "comprehensive" responses to 93.8% of questions related to "efficacy, eligibility and procedure options"; 93.3% related to "preoperative preparation"; 85.3% related to "recovery, risks, and complications"; 88.2% related to "lifestyle changes"; and 66.7% related to "other". The model provided reproducible answers to 137 (90.7%) of questions. CONCLUSION: The large language model ChatGPT often provided accurate and reproducible responses to common questions related to bariatric surgery. ChatGPT may serve as a helpful adjunct information resource for patients regarding bariatric surgery in addition to standard of care provided by licensed healthcare professionals. We encourage future studies to examine how to leverage this disruptive technology to improve patient outcomes and quality of life.

Assessing the performance of ChatGPT in answering questions regarding cirrhosis and hepatocellular carcinoma.

BACKGROUND/AIMS: Patients with cirrhosis and hepatocellular carcinoma (HCC) require extensive and personalized care to improve outcomes. ChatGPT (Generative Pre-trained Transformer), a large language model, holds the potential to provide professional yet patient-friendly support. We aimed to examine the accuracy and reproducibility of ChatGPT in answering questions regarding knowledge, management, and emotional support for cirrhosis and HCC. METHODS: ChatGPT's responses to 164 questions were independently graded by two transplant hepatologists and resolved by a third reviewer. The performance of ChatGPT was also assessed using two published questionnaires and 26 questions formulated from the quality measures of cirrhosis management. Finally, its emotional support capacity was tested. RESULTS: We showed that ChatGPT regurgitated extensive knowledge of cirrhosis (79.1% correct) and HCC (74.0% correct), but only small proportions (47.3% in cirrhosis, 41.1% in HCC) were labeled as comprehensive. The performance was better in basic knowledge, lifestyle, and treatment than in the domains of diagnosis and preventive medicine. For the quality measures, the model answered 76.9% of questions correctly but failed to specify decision-making cut-offs and treatment durations. ChatGPT lacked knowledge of regional guidelines variations, such as HCC screening criteria. However, it provided practical and multifaceted advice to patients and caregivers regarding the next steps and adjusting to a new diagnosis. CONCLUSION: We analyzed the areas of robustness and limitations of ChatGPT's responses on the management of cirrhosis and HCC and relevant emotional support. ChatGPT may have a role as an adjunct informational tool for patients and physicians to improve outcomes.

Human anterior insula signals salience and deviations from expectations via bursts of beta oscillations.

Functional imaging studies indicate that the insula encodes the salience of stimuli and deviations from expectations, signals that can mobilize cognitive resources and facilitate learning. However, there is no information about the physiological underpinnings of these phenomena beyond changing BOLD signals. To shed light on this question, we analyzed intracerebral local field potentials (LFPs) in five patients with epilepsy of both genders performing a virtual reality task that featured varying odds of monetary rewards and losses. Upon outcome disclosure, the anterior (but not the posterior) insula generated bursts of beta oscillations whose amplitudes were lower for neutral than positive and negative outcomes, consistent with a salience signal. Moreover, beta burst power was higher when outcomes deviated from expectations, whether the outcome was better or worse than expected, indicating that the insula provides an unsigned prediction error signal. Last, in relation to insular beta bursts, many higher-order cortical areas exhibited robust changes in LFP activity that ranged from spectrally nonspecific or differentiated increases in gamma power to bursts of beta activity that closely resembled the insular beta bursts themselves. Critically, the activity of these other cortical regions was more closely tied in time to insular bursts than task events, suggesting that they are associated with particularly significant cognitive phenomena. Overall, our findings suggest that the insula signals salience and prediction errors via amplitude modulations of beta bursts, which coincide with the near simultaneous recruitment of vast cortical territories.NEW & NOTEWORTHY Functional imaging studies indicate that the anterior insula encodes salience and deviations from expectations. Beyond changing BOLD signals, however, the physiological underpinnings of these signals are unknown. By recording local field potentials in patients with epilepsy, we found that the anterior insula generates large bursts of beta oscillations whose amplitude is modulated by the salience of outcomes and deviations from expectations. Moreover, insular beta bursts coincide with the activation of many high-order cortical areas.

Scalp recorded theta activity is modulated by reward, direction, and speed during virtual navigation in freely moving humans.

Theta oscillations (~ 4-12 Hz) are dynamically modulated by speed and direction in freely moving animals. However, due to the paucity of electrophysiological recordings of freely moving humans, this mechanism remains poorly understood. Here, we combined mobile-EEG with fully immersive virtual-reality to investigate theta dynamics in 22 healthy adults (aged 18-29 years old) freely navigating a T-maze to find rewards. Our results revealed three dynamic periods of theta modulation: (1) theta power increases coincided with the participants' decision-making period; (2) theta power increased for fast and leftward trials as subjects approached the goal location; and (3) feedback onset evoked two phase-locked theta bursts over the right temporal and frontal-midline channels. These results suggest that recording scalp EEG in freely moving humans navigating a simple virtual T-maze can be utilized as a powerful translational model by which to map theta dynamics during "real-life" goal-directed behavior in both health and disease.

Qualitative Validation of a Novel VR Program for Irritable Bowel Syndrome: A VR1 Study.

INTRODUCTION: Although gut-directed psychotherapies are effective for irritable bowel syndrome (IBS), they are rarely prescribed, given a paucity of trained clinicians. Virtual reality (VR) offers a solution by allowing patients to self-practice these techniques in a standardized manner. METHODS: A multidisciplinary team developed IBS/VR, a program that transports users into immersive VR worlds that teach patients about the brain-gut axis, cognitive behavioral therapy, and gut-directed meditation. We tested IBS/VR in Rome IV IBS patients and used inductive analysis to evaluate perceptions and identify recommendations. RESULTS: We achieved thematic saturation after 9 interviews; 3 additional interviews revealed no emergent themes. After making 23 software changes based on patient feedback, we conducted 3 additional interviews which confirmed thematic saturation (N = 15 total). DISCUSSION: This study offers initial validation of the first VR program designed for IBS.

Using Virtual Reality to Improve Antiretroviral Therapy Adherence in the Treatment of HIV: Open-Label Repeated Measure Study.

BACKGROUND: Nonadherence to HIV medications is a serious unsolved problem and is a major cause of morbidity and mortality in the HIV-positive population. Although treatment efficacy is high if compliance is greater than 90%, about 40% of people with HIV do not meet this threshold. OBJECTIVE: This study aimed to test a novel approach to improve medication adherence by using a low-cost virtual reality (VR) experience to educate people with HIV about their illness. We hypothesized that people with HIV would be more likely to be compliant with the treatment following the 7-minute experience and, therefore, should have decreasing viral load (VL), increasing cluster of differentiation 4+ (CD4+) cell counts, and improved self-reported adherence. METHODS: We showed the VR experience to 107 participants with HIV at a county hospital in Los Angeles, California. Participants were asked to self-report how often they take their medications on a Likert-scale. The self-reported question (SRQ) was given before and at least 2 weeks after the VR experience. We also compared VL and CD4+ cell counts before and on average 101 days after the experience. VL and CD4+ were obtained per the clinic's standard care protocol. Two-tailed paired t tests were performed on the initial and follow-up SRQ scores, VL, and CD4+. We restricted the CD4+ analysis to participants who had a pre-CD4+ below normal (defined as 500 cells/mm3). To reduce the possibility that VL were trending down and CD4+ were trending up regardless of the VR experience, 2 serial VL and CD4+ obtained before the experience were also compared and analyzed. Immediately following the VR experience, participants were given a 4-question Likert-type postexperience questionnaire (PEQ) that assessed their opinions about the experience. RESULTS: SRQ scores improved from pre to post experience with high significance (P<.001). VL decreased from pre to post experience by 0.38 log10 copies/mL (95% CI 0.06-0.70; P=.02). In contrast, the 2 serial VL obtained before the experience showed no statistically significant changes. There was also a statistically significant increase in CD4+ (95% CI -3.4 to -54.3 cells/mm3; P=.03). Analysis of the PEQ revealed that VR was comfortable for almost all of the participants and that most participants believed the experience to be educational and that it would improve their medication adherence. CONCLUSIONS: The findings suggest that the low-cost VR experience caused an increased rate of antiretroviral therapy adherence that resulted in a decrease of VL and an increase of CD4+. Further studies are required to explore the duration of this effect and whether these results are generalizable to other treatment settings and populations.