Development of a virtual reality based microsurgery trainer

Master'sMASTER OF ENGINEERIN

Factors of Micromanipulation Accuracy and Learning

Micromanipulation refers to the manipulation under a microscope in order to perform delicate procedures. It is difficult for humans to manipulate objects accurately under a microscope due to tremor and imperfect perception, limiting performance. This project seeks to understand factors affecting accuracy in micromanipulation, and to propose strategies for learning improving accuracy. Psychomotor experiments were conducted using computer-controlled setups to determine how various feedback modalities and learning methods can influence micromanipulation performance. In a first experiment, static and motion accuracy of surgeons, medical students and non-medical students under different magniification levels and grip force settings were compared. A second experiment investigated whether the non-dominant hand placed close to the target can contribute to accurate pointing of the dominant hand. A third experiment tested a training strategy for micromanipulation using unstable dynamics to magnify motion error, a strategy shown to be decreasing deviation in large arm movements. Two virtual reality (VR) modules were then developed to train needle grasping and needle insertion tasks, two primitive tasks in a microsurgery suturing procedure. The modules provided the trainee with a visual display in stereoscopic view and information on their grip, tool position and angles. Using the VR module, a study examining effects of visual cues was conducted to train tool orientation. Results from these studies suggested that it is possible to learn and improve accuracy in micromanipulation using appropriate sensorimotor feedback and training

Development of a virtual reality based microsurgery trainer

Master'sMASTER OF ENGINEERIN

Enhancing learning outcomes through multisensory integration: A fMRI study of audio-visual training in virtual reality

The integration of information from different sensory modalities is a fundamental process that enhances perception and performance in real and virtual environments (VR). Understanding these mechanisms, especially during learning tasks that exploit novel multisensory cue combinations provides opportunities for the development of new rehabilitative interventions. This study aimed to investigate how functional brain changes support behavioural performance improvements during an audio-visual (AV) learning task. Twenty healthy participants underwent a 30 min daily VR training for four weeks. The task was an AV adaptation of a ‘scanning training’ paradigm that is commonly used in hemianopia rehabilitation. Functional magnetic resonance imaging (fMRI) and performance data were collected at baseline, after two and four weeks of training, and four weeks post-training. We show that behavioural performance, operationalised as mean reaction time reduction in VR, significantly improves. In separate tests in a controlled laboratory environment, we showed that the behavioural performance gains in the VR training environment transferred to a significant mean RT reduction for the trained AV voluntary task on a computer screen. Enhancements were observed in both the visual-only and AV conditions, with the latter demonstrating a faster response time supported by the presence of audio cues. The behavioural learning effect also transfers to two additional tasks that were tested: a visual search task and an involuntary visual task. Our fMRI results reveal an increase in functional activation (BOLD signal) in multisensory brain regions involved in early-stage AV processing: the thalamus, the caudal inferior parietal lobe and cerebellum. These functional changes were only observed for the trained, multisensory, task and not for unimodal visual stimulation. Functional activation changes in the thalamus were significantly correlated to behavioural performance improvements. This study demonstrates that incorporating spatial auditory cues to voluntary visual training in VR leads to augmented brain activation changes in multisensory integration, resulting in measurable performance gains across tasks. The findings highlight the potential of VR-based multisensory training as an effective method for enhancing cognitive function and as a potentially valuable tool in rehabilitative programmes

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 13th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2022, held in Hamburg, Germany, in May 2022. The 36 regular papers included in this book were carefully reviewed and selected from 129 submissions. They were organized in topical sections as follows: haptic science; haptic technology; and haptic applications

Electrophysiologic assessment of (central) auditory processing disorder in children with non-syndromic cleft lip and/or palate

Session 5aPP - Psychological and Physiological Acoustics: Auditory Function, Mechanisms, and Models (Poster Session)Cleft of the lip and/or palate is a common congenital craniofacial malformation worldwide, particularly non-syndromic cleft lip and/or palate (NSCL/P). Though middle ear deficits in this population have been universally noted in numerous studies, other auditory problems including inner ear deficits or cortical dysfunction are rarely reported. A higher prevalence of educational problems has been noted in children with NSCL/P compared to craniofacially normal children. These high level cognitive difficulties cannot be entirely attributed to peripheral hearing loss. Recently it has been suggested that children with NSCLP may be more prone to abnormalities in the auditory cortex. The aim of the present study was to investigate whether school age children with (NSCL/P) have a higher prevalence of indications of (central) auditory processing disorder [(C)APD] compared to normal age matched controls when assessed using auditory event-related potential (ERP) techniques. School children (6 to 15 years) with NSCL/P and normal controls with matched age and gender were recruited. Auditory ERP recordings included auditory brainstem response and late event-related potentials, including the P1-N1-P2 complex and P300 waveforms. Initial findings from the present study are presented and their implications for further research in this area —and clinical intervention—are outlined. © 2012 Acoustical Society of Americapublished_or_final_versio

C-9 and Other Microgravity Simulations

This document represents a summary of medical and scientific evaluations conducted aboard the C-9 or other NASA-sponsored aircraft from June 30, 2006, to June 30, 2007. Included is a general overview of investigations manifested and coordinated by the Human Adaptation and Countermeasures Office. A collection of brief reports that describe tests conducted aboard the NASA-sponsored aircraft follows the overview. Principal investigators and test engineers contributed significantly to the content of the report, describing their particular experiment or hardware evaluation. Although this document follows general guidelines, each report format may vary to accommodate differences in experiment design and procedures. This document concludes with an appendix that provides background information about the Reduced Gravity Program