LENS Neurofeedback offers hope to victims of stroke, brain trauma, and other conditions

I do wonder how documented the research is on the usefulness of this.
http://www.redwoodtimes.com/garbervillenews/ci_21304600

LENS neurofeedback provider Melissa Wessel drives from Windsor in Sonoma County to Humboldt County every other week to see her local clients, who include people recovering from brain damage, stroke, and a variety of neurological conditions, including post-traumatic stress disorder, attention deficit disorder, autism, anxiety, and depression.
LENS, which stands for "Low Energy Neurofeedback System," uses a low-powered electromagnetic field to carry feedback from specific sites on a client’s brain. This feedback, which is slightly different than the signal sent from the brain, "gently nudges" an injured or disordered brain toward better function.
The history of LENS began about 40 years ago when the public first became aware of biofeedback as a treatment for a variety of conditions including stress, depression, anxiety, and pain.
"If you remember, with biofeedback you would be hooked up with something on your hand or arm, and you would work at changing your body temperature or your heart rate, and you would learn how to control your body and your biological functions," Wessel recalled.
With neurofeedback, which was originally called "brain entrainment," the client was connected to a computer that read his or her brainwaves. The client then played a game, such as driving a virtual car down a road on the computer screen, using only feedback from his or her brain.
The brain produces several kinds of waves, including alpha waves, beta waves, and delta waves. In different illnesses or conditions, one or more categories of waves originating from various parts of the brain can be hyperactive or hypersuppressed, causing the client’s symptoms.
Rest at the link.