Effects of Parkinson’s disease on optic flow perception for heading direction during navigation

Visuoperceptual disorders have been identified in individuals with Parkinson’s disease (PD) and may affect the perception of optic flow for heading direction during navigation. Studies in healthy subjects have confirmed that heading direction can be determined by equalizing the optic flow speed (OS) between visual fields. The present study investigated the effects of PD on the use of optic flow for heading direction, walking parameters, and interlimb coordination during navigation, examining the contributions of OS and spatial frequency (dot density). Twelve individuals with PD without dementia, 18 age-matched normal control adults (NC), and 23 young control adults (YC) walked through a virtual hallway at about 0.8 m/s. The hallway was created by random dots on side walls. Three levels of OS (0.8, 1.2, and 1.8 m/s) and dot density (1, 2, and 3 dots/m2) were presented on one wall while on the other wall, OS and dot density were fixed at 0.8 m/s and 3 dots/m2, respectively. Three-dimensional kinematic data were collected, and lateral drift, walking speed, stride frequency and length, and frequency, and phase relations between arms and legs were calculated. A significant linear effect was observed on lateral drift to the wall with lower OS for YC and NC, but not for PD. Compared to YC and NC, PD veered more to the left under OS and dot density conditions. The results suggest that healthy adults perceive optic flow for heading direction. Heading direction in PD may be more affected by the asymmetry of dopamine levels between the hemispheres and by motor lateralization as indexed by handedness.Published versio

Entrenamiento motor en el continuo de la realidad a la virtualidad

Introducción. La trasformación de la capacidad de movimiento de las personas es un reto que el fisioterapeuta asume como estrategia de aprendizaje motor.Objetivo. Plantear los referentes teóricos y prácticos más relevantes en el uso de ambientes terapéuticos en el continuo de la realidad a la virtualidad en el entrenamiento motor de pacientes con accidente cerebrovascular y enfermedad de Parkinson. Materiales y métodos. Revisión de la literatura que analiza y aporta de manera conceptual, en el área de la rehabilitación y la fisioterapia, información sobre entrenamiento y aprendizaje motor.Resultados. Se evidencia potencial en el uso de la realidad virtual para la rehabilitación de alteraciones del movimiento debidas a disfunciones neurológicas. Las herramientas tecnológicas propias de la realidad virtual permiten un mayor conocimiento de los resultados con respecto a las características del movimiento, lo cual ayuda a mejorar el aprendizaje motor, en comparación con el entrenamiento tradicional.Conclusiones. Se requiere objetivar el proceso de rehabilitación para medir con precisión los cambios que producen estrategias de aprendizaje en las capacidades de movimiento de las personas con deficiencias del sistema neuromuscular para generar evidencia del impacto que tienen los programas de entrenamiento motor en el continuo de la realidad a la virtualidad.Introduction: The transformation of people’s movement capacity is a challenge that physiotherapists address as a motor learning strategy.Objective: To gather the most relevant theoretical and practical references on the use of therapeutic environments in the realityvirtuality continuum regarding motor training in stroke and Parkinson’s patients.Materials and methods: Literature review that analyzes and contributes conceptual information on training and motor learning in the field of rehabilitation and physiotherapy.Results: The potential of the use of virtual reality in movement disorder rehabilitation processes due to neurological dysfunctions is observed. The technological tools for virtual reality allow a better understanding of the results with respect to the characteristics of the movement, which helps to improve motor learning in comparison with traditional training.Conclusions: It is necessary to objectify the rehabilitation process to accurately measure the changes generated by learning strategies in the movement abilities of patients with neuromuscular system disorders in order to obtain evidence of the impact that motor training programs have on the reality-virtuality continuum

Virtual Aesthetics and Ethical Communication: Towards Virtuous Reality Design

This thesis argues that ethics can and should be applied to Second Life avatar design and behavior. Second Life is a unique virtual reality due to its connection to the physical world primarily through financial devices. Users buy and sell virtual and physical goods over these networks; the avatar, it is argued, is the primary instrument for persuasion in these contexts. Avatars facilitate a virtual aesthetic that is primarily \u27natural.\u27 By creating aesthetic avatars, the developers of Second Life enable audiences to affectively associate with other \u27residents.\u27 Not only is the avatar designed for aesthetic appeal, but it enables users to move, act, and interact in an online environment--to vicariously experience the emotions that accompany those actions. In the real world, individuals\u27 actions have ethical consequences. Behavior in Second Life, it is argued, should be subject to ethics as determined by democratic communities of users