Quantifying time perception during virtual reality gameplay using a multimodal biosensor-instrumented headset: a feasibility study.

We have all experienced the sense of time slowing down when we are bored or speeding up when we are focused, engaged, or excited about a task. In virtual reality (VR), perception of time can be a key aspect related to flow, immersion, engagement, and ultimately, to overall quality of experience. While several studies have explored changes in time perception using questionnaires, limited studies have attempted to characterize them objectively. In this paper, we propose the use of a multimodal biosensor-embedded VR headset capable of measuring electroencephalography (EEG), electrooculography (EOG), electrocardiography (ECG), and head movement data while the user is immersed in a virtual environment. Eight gamers were recruited to play a commercial action game comprised of puzzle-solving tasks and first-person shooting and combat. After gameplay, ratings were given across multiple dimensions, including (1) the perception of time flowing differently than usual and (2) the gamers losing sense of time. Several features were extracted from the biosignals, ranked based on a two-step feature selection procedure, and then mapped to a predicted time perception rating using a Gaussian process regressor. Top features were found to come from the four signal modalities and the two regressors, one for each time perception scale, were shown to achieve results significantly better than chance. An in-depth analysis of the top features is presented with the hope that the insights can be used to inform the design of more engaging and immersive VR experiences.

Virtual reality and non-invasive brain stimulation for rehabilitation applications: a systematic review.

The present article reports the results of a systematic review on the potential benefits of the combined use of virtual reality (VR) and non-invasive brain stimulation (NIBS) as a novel approach for rehabilitation. VR and NIBS are two rehabilitation techniques that have been consistently explored by health professionals, and in recent years there is strong evidence of the therapeutic benefits of their combined use. In this work, we reviewed research articles that report the combined use of VR and two common NIBS techniques, namely transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS). Relevant queries to six major bibliographic databases were performed to retrieve original research articles that reported the use of the combination VR-NIBS for rehabilitation applications. A total of 16 articles were identified and reviewed. The reviewed studies have significant differences in the goals, materials, methods, and outcomes. These differences are likely caused by the lack of guidelines and best practices on how to combine VR and NIBS techniques. Five therapeutic applications were identified: stroke, neuropathic pain, cerebral palsy, phobia and post-traumatic stress disorder, and multiple sclerosis rehabilitation. The majority of the reviewed studies reported positive effects of the use of VR-NIBS. However, further research is still needed to validate existing results on larger sample sizes and across different clinical conditions. For these reasons, in this review recommendations for future studies exploring the combined use of VR and NIBS are presented to facilitate the comparison among works.

YOGA AND THE INTERPLAY BETWEEN ATTENTIONAL LOAD AND EMOTION INTERFERENCE.

This study compared 45 yoga practitioners (M age = 29.7 yr., SD = 6.4) and 45 matched controls (M age = 29.3 yr., SD = 6.2) on the performance of a behavioral task that assessed negative emotion interference during a high- and a low-attentional demand condition, as well as on state and trait anxiety scores. Outcomes were also compared between beginner and advanced practitioners. For the behavioral task, the final sample comprised 36 yoga and 38 control participants. The yoga group presented lower emotion interference in the high attentional condition, compared to the low attentional condition; rated emotional images as less unpleasant, compared to controls; and reported lower state and trait anxiety scores relative to controls. Also, emotion interference in the low attentional condition was lower among advanced practitioners and state anxiety was lower among practitioners attending more than two weekly yoga classes. The results suggested that yoga may help improve self-regulatory skills and lower anxiety. The psychological mechanisms underlying the relationship between yoga and emotion regulation should be further investigated in longitudinal studies.

Stem cell grafts as therapeutic tools for central nervous system disorders

The last few years have seen a growing interest in stem cell research. The media has helped to keep attention to the subject making it as popular as therapeutic cloning. A number of studies highlighted the importance of stem cells as prospective therapy for neurodegenerative conditions. The possibility of successful treatment for such pathologies using stem cells has raised enormous hope. Whilst in some countries biotechnologists have realised the commercial potential of the field, human stem cell research and its clinical applications have constantly been subject of ethical and legal debate. The present review brings an overview of recent aspects of stem cell research for central nervous system disorders, with special attention to Parkinson's and Alzheimer's diseases, cerebral ischemic insult and spinal cord injury. Furthermore, the ethical implications regarding the use of embryonic stem cells as a fundamentally more promising cell type are discussed.

Stem cell grafts as therapeutic tools for central nervous system disorders

The last few years have seen a growing interest in stem cell research. The media has helped to keep attention to the subject making it as popular as therapeutic cloning. A number of studies highlighted the importance of stem cells as prospective therapy for neurodegenerative conditions. The possibility of successful treatment for such pathologies using stem cells has raised enormous hope. Whilst in some countries biotechnologists have realised the commercial potential of the field, human stem cell research and its clinical applications have constantly been subject of ethical and legal debate. The present review brings an overview of recent aspects of stem cell research for central nervous system disorders, with special attention to Parkinson's and Alzheimer's diseases, cerebral ischemic insult and spinal cord injury. Furthermore, the ethical implications regarding the use of embryonic stem cells as a fundamentally more promising cell type are discussed.(AU)

Alzheimer's disease and neural transplantation as prospective cell therapy.

It has long been recognised that Alzheimer's disease (AD) patients present an irreversible decline of cognitive functions as consequence of cell deterioration in the forebrain cholinergic projection system (FCPS), particularly, in a structure called nucleus basalis of Meynert (nbM). The reduction of the number of cholinergic cells in the FCPS disrupts not just its functions and direct connexions but also the modulation of other systems causing interference in several aspects of behavioural performance including arousal, attention, learning and emotion. It is also common knowledge that AD is an untreatable degenerative disease with very few temporary and palliative drug therapies. Neural stem cell (NSC) grafts present a potential and innovative strategy for the treatment of many disorders of the central nervous system including AD, with the possibility of providing a more permanent remedy than present drug treatments. After grafting, these cells have the capacity to migrate to lesioned regions of the brain and differentiate into the necessary type of cells that are lacking in the diseased brain, supplying it with the cell population needed to promote recovery. The present article aims to review the main aspects of Alzheimer's disease and to explore the use of neural stem cells grafts as alternative treatment for the consequent functional deterioration.