Optimizing Motor Imagery Neurofeedback with Multimodal Immersive Virtual Reality and Motor Priming

Stroke is among the leading causes of long-term disabilities leaving an increasing number of people with cognitive and motor impairments, loss of independence in their daily life and with a high societal cost. So far, the development of Brain–Computer Interfaces (BCIs) that translate brain activity into control signals in computers or external devices provides new strategies to overcome stroke-related motor limitations.

Recent studies demonstrated the brain's capacity for functional and structural plasticity and recovery even in severe chronic stroke. However, it is not fully clear how we can exploit the neurobiological mechanisms underlying recovery. This is the case for restorative BCI research. There is currently no standardized and accepted treatment for the use of BCIs with patients suffering from acute or chronic motor impairments.

In this study we investigated with 9 healthy participants the role of multimodal virtual reality (VR) simulations and of motor priming (MP) in a motor imagery BCI training. In order to overcome the current limitations and improve MI-BCI based motor rehabilitation paradigms, we have developed a novel prototype that makes use of multimodal feedback, in an immersive VR environment delivered through a Head Mounted Display (HMD), and that is integrated in a MI-BCI motor training task. Subsequently we designed, assessed and compared 3 MI-BCI neurofeedback paradigms based on the following criteria: 1) to improve user performance, and 2) to maximize the engagement of sensory-motor networks in the MI-BCI task. We studied the role of motor priming and of multimodal VR feedback compared to a control MI-BCI setting using the standard feedback provided by bars and arrows.

Our findings show improved BCI performance for VR and MP conditions, as well as the capacity to modulate and enhance brain activity patterns. Our data suggest that both VR and MP can be useful to promote neural activation and neuroplastic changes in the rehabilitation of stroke patients a motor imagery neurofeedback paradigm.

Reference:

Optimizing Motor Imagery Neurofeedback through the Use of Multimodal Immersive Virtual Reality and Motor Priming. A Vourvopoulos, J Muñoz, S Bermúdez i Badia, 2015 International Conference on Virtual Rehabilitation (ICVR), Valencia, 2015.