Stroke help from brain link reported
Stroke patients could improve motor function by connecting brain their signals with a computer.
University of Adelaide researchers have published a proof-of-principle paper describing how a brain-computer interface (BCI) can be used to produce a 36 per cent improvement in motor function of a stroke-damaged hand.
The BCI measures brain electrical signals via nodes on the surface of the scalp.
When the subject imagines performing a specific motor function, like grasping an object, the BCI takes the electrical signals and transmits them to a computer, which uses advanced software to interpret brain signals and supplies a sensory feedback to the hand.
“In the majority of strokes, the area of the brain that sends motor commands to the muscles becomes partly damaged and thereby degrades motor functions of the affected parts,” says researcher Dr Sam Darvishi.
“During the early phases of motor learning (such as when we are toddlers) our brain and body learn how to work in harmony when the brain commands the target muscles and then receives feedback via seeing and feeling the body movement. After a stroke the brain needs to re-train the lost skills.
“BCIs have been proposed as an alternate therapy for stroke patients. They have shown some level of promise but, to date, haven’t been particularly effective.
“Our theory is that to achieve clinical results with BCIs we need to have the right feedback to the brain at the right time; we need to provide the same feedback that we receive during natural motor learning, when we are seeing and feeling the body’s movement. We also found there should be a short delay between the brain activation and the activation of target muscles.”
The researchers designed a specific BCI to meet these requirements. In a single case study of one patient they achieved 36 per cent improvement in hand motor function in just 10 training sessions of 30 minutes each.
“This was only a single patient so we can’t generalise the outcome to a whole stroke population,” says Dr Darvishi.
“However it certainly shows enough promise for a larger study of stroke patients to see if this could be a feasible therapy for stroke rehabilitation.
“This would be a major step towards helping stroke patients recover from debilitating damage.”