The common theme that arises from central nervous system (CNS) injury research is how basic studies can inform the development of therapies. In each of the primary CNS injuries—spinal cord injury, stroke, and brain tumors—treatments are lacking, in large part because of the complexity of the underlying processes.

Research has therefore mainly focused on unraveling the processes of cell death, nerve regeneration, and tumor genesis, with the ever-present goal of translating that knowledge into molecularly targeted treatments that prevent or repair nervous system damage.

Harnessing Thoughts

In one of the year’s biggest headline grabbers, a paralyzed man controlled a computer using thoughts. This advance is the culmination of decades of basic research on the brain’s motor control center (also discussed in the Neuroethics section, page 36). A pilot study on this one patient, reported in Nature by John Donoghue of Brown University and a Harvard-based team of collaborators, proved the concept that a brain-computer interface can record neural activity from a person’s primary motor cortex and translate it into specific actions on external devices.¹

Brain-computer interface: In a pilot study, a brain-computer interface allowed a single patient with paralysis to operate a computer using only his thoughts. Paired with a muscle stimulator system, such technology may one day allow people who are paralyzed to move their limbs again. (Illustration courtesy of Cyberkinetics Neurotechnology Systems, Inc.)

The man in the study, paralyzed from the neck down in a spinal cord injury three years ago, was able to open e-mail messages, operate a television and light switches, open and close a prosthetic hand, and perform rudimentary actions with a multijointed arm. The work represents an early step toward thought-powered robotics, which are envisioned as tools to help restore some degree of independence to people paralyzed by central nervous system damage. The authors were careful to note that the technology requires further refinement before it can be practically applied beyond a research setting. 

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