Comparison of Immersive and Non-Immersive Virtual Reality Rehabilitation in Parkinson's Disease

Parkinson's disease is a progressive neurodegenerative disorder characterized by motor impairments such as gait dysfunction, postural instability, mobility limitations, and freezing of gait, as well as cognitive deficits affecting attention, executive function, and dual-task performance. These impairments contribute substantially to disability, fall risk, and reduced quality of life.

Virtual reality-based rehabilitation has emerged as a promising approach for delivering task-oriented, repetitive, and engaging interventions that simultaneously address motor and cognitive domains. However, immersive and non-immersive virtual reality systems differ substantially in their interaction characteristics, sensory feedback, and degree of user immersion, and their comparative effects in Parkinson's disease remain insufficiently understood.

The purpose of this pilot randomized comparative study is to evaluate the feasibility, safety, and preliminary clinical effects of immersive virtual reality (IVR) compared with non-immersive virtual reality (NIVR) rehabilitation in individuals with idiopathic Parkinson's disease.

Participants diagnosed with Parkinson's disease will be allocated to one of two intervention groups. The IVR group will receive rehabilitation using the KINESIX XR platform delivered through a head-mounted display with real-time motion tracking and three-dimensional interactive environments. The NIVR group will receive rehabilitation using the Active Arcade exergaming platform delivered on a tablet device. Both interventions will be supervised and delivered over a six-week period, consisting of ten treatment sessions in addition to baseline and post-intervention assessments.

Outcome measures will include spatiotemporal gait parameters, functional mobility, dual-task performance, turning ability, freezing of gait symptoms, cognitive function, adherence to treatment, and safety outcomes. Assessments will be conducted at baseline and immediately following completion of the intervention program.

The results of this study are expected to provide preliminary evidence regarding the differential motor and cognitive responses associated with immersive and non-immersive virtual reality rehabilitation and will support the development of future adequately powered clinical trials in Parkinson's disease rehabilitation.

Inclusion criteria

• Age between 45 and 75 years.
• Diagnosis of idiopathic Parkinson's disease.
• Hoehn and Yahr stage between 1.5 and 4.
• Ability to walk independently or with an assistive device (cane or walker).
• Low to moderate fall risk, defined as a Timed Up and Go (TUG) score <20 seconds.
• Ability to provide written informed consent.

Exclusion criteria

• Diagnosis of other neurological or movement disorders.
• Severe cognitive impairment, defined as a Montreal Cognitive Assessment (MoCA) score <18.
• Severe visual impairment not correctable with lenses.
• History of epilepsy.
• Uncontrolled psychiatric disorders.
• Previous deep brain stimulation.