The IpsiHand home system, which reads electrical brain signals, improved arm movement after stroke more than exercise
The IpsiHand home system, which reads electrical brain signals, improved arm movement after stroke more than exercise
On August 13, the randomized BCI-REHAB trial was published. Its primary analysis included 62 people with chronic impairment of arm movement after stroke. The trial compared the IpsiHand home brain-computer interface with exercise. The system converts an attempt to move the affected hand into finger movement, while the control group exercised the arm on the same schedule.
For some people, an attempt to move the arm after a stroke no longer produces movement of the hand. IpsiHand builds rehabilitation around this attempt. EEG, which records electrical brain activity from the surface of the head, detects a signal pattern associated with imagined movement of the affected hand in the hemisphere not damaged by the stroke. When the system recognizes this pattern, a device attached to the hand opens and closes the fingers into a three-finger pinch.
Earlier studies showed that this signal could be used to control hand movement. BCI-REHAB tested whether coupling the signal to movement improved rehabilitation more than an equal amount of home exercise. Before assignment, each participant was tested to determine whether the EEG signal was strong enough to control the device. The primary analysis included 37 people assigned to IpsiHand and 25 assigned to a program of hand, wrist, elbow, and shoulder movements. The program also included everyday tasks, such as opening a drawer or lifting a cup. Both groups were instructed to train for one hour a day, five days a week, for 12 weeks.
The UEFM scale rates arm movement from 0 to 66 points. It was measured before training began and after 12 weeks. Specialists who did not know each participant's group assignment later reviewed video recordings of the assessments. In the primary statistical model, the mean improvement was 6.0 points with IpsiHand and 1.5 points with exercise, a difference of 4.5 points. The researchers had predefined an improvement of 5.25 points as clinically meaningful. In their model, 55.5% of participants using IpsiHand reached this threshold, compared with 9.6% in the control group.
On average, 5.5 years had passed since the stroke. Over 12 weeks, coupling an attempt to move with finger movement produced a greater improvement in arm function in this group than home exercise of the same duration.