Virtual reality is a video game in which a person and their real-time movements are represented on a screen in a virtual environment. This study will compare the use of multi-user virtual reality (VR) to single-user VR to determine if either provides superior engagement in upper extremity therapy and greater motivation to perform repetitive training.

Stroke survivors will participate in a longitudinal study in which they will have the opportunity to perform rehabilitative training with multi-user VR and single-user VR modes in their homes. They will use each mode for 2 weeks, completing 4 session per week, each session is 1 hour long. Upper extremity motor control, level of engagement, and active range of motion will be assessed at time points during the intervention period.

Subject evaluations will take place before the intervention, at the midpoint of intervention (between switching from multi-user to single-user modes, or vice versa), and at the end of the intervention.

The investigators hope to address two aims:

Aim 1: To determine if the use in-home multi-user virtual reality treatment results in greater engagement in therapy compared with in-home single user virtual reality treatment.

Aim 2: To determine if in-home virtual reality treatment results in greater practice

The investigators hypothesize that stroke survivors will be more engaged in therapy when training with the multi-user VR system and this will translate into greater practice.

Inclusion Criteria:

• Are between the ages of 21 and 80
• Experienced a single stroke at least 6 months prior to enrollment
• Have moderate arm impairment as indicated by a score between 4 and 6 on the Chedoke-McMaster Stroke Assessment, arm subscale
• Live within 20 miles of the Rehabilitation Institute of Chicago (as study personnel will need to travel to their home)

Exclusion Criteria:

• Other neurological, neuromuscular, or orthopedic disease
• Pain in the upper extremity with movements required in the treatment
• Contracture that limits use of the VR system
• Vision problems which would preclude the ability to use the VR system
• Cognitive or language deficits that would prevent them from understanding the tasks
• Concurrent enrollment in another intervention study involving the affected arm or hand
• Botox injection in the arm within the previous 6 months