Dr. Gerwin SchalkThe NewScientist article Brain blanket boosts mind control said
With a sheet of electrodes placed over the brain, people can quickly learn to move a cursor around a computer screen using their thoughts. Early trials suggest that this new procedure could overtake more established brain-computer interfaces (BCIs).
BCIs will one day transform the lives of people with disabilities and neurological disorders affecting their ability to move or communicate, says neuroscientist Gerwin Schalk at the Wadsworth Center, New York State Department of Health, US.
The two established techniques involve inserting electrodes into the brain or attaching them onto the scalp. These approaches have let people control robotic limbs, steer wheelchairs, type messages and walk in virtual worlds using thought alone.
Schalk and colleagues at Albany Medical College, Washington University in St Louis, University of Washington, Seattle, and the University of Wisconsin at Madison, all US, think a third approach will face fewer hurdles.
They cover part of the brain’s surface with a polymer sheet containing a grid of electrodes 2 millimeters in diameter and spaced 10 mm apart, a method called electrocorticography (ECOG). Such electrode grids are often placed in people with severe epilepsy to identify the focus of seizures within the brain.
“These grids are thin like a sheet of paper,” says Schalk. “The electrodes record signals similar to those recorded by electrodes on the scalp, but with much greater fidelity.”
Gerwin Schalk, Ph.D. is
Research Scientist, Wadsworth Center, Nervous System Disorders, New York
State Department of Health. He is also
Department of Neurology, Albany Medical College, Albany, New York and
Adjunct Assistant Professor,
Department of Neurosurgery, Washington University in St.
Louis, St. Louis, Missouri.
His main professional interest is technical innovation at the intersection of science, engineering, and economics. His current primary research interest is the further development of brain-computer interface (BCI) technology.
BCI systems are devices that can provide non-muscular communication and control options to people with severe motor disabilities. To remove the impediments that currently impede translation of BCI technical demonstrations into clinical practice, Gerwin is currently designing innovative software and novel signal processing techniques, and validating a new sensor modality.
The software engineering efforts are centered on BCI2000, a general-purpose software system for brain-computer interfacing and brain monitoring. This NIH-funded system supports implementation of any BCI system and already supports a variety of input devices, brain signals, and user applications. BCI2000 is currently in use by more than 120 laboratories world-wide that use the system for a variety of studies.
The signal processing efforts are focused on the development and implementation of SIGFRIED, a novel real-time signal visualization technique for complex brain signals. SIGFRIED can translate ongoing complex brain signals into an output that can be easily understood by non-experts. Possible applications include intraoperative mapping of cortical function and BCI control that does not require laborious calibration by BCI experts.
Sensor validation is centered on the evaluation of sensors placed subdurally on the surface of the brain as a signal source for BCI control. These electrocorticographic (ECoG) sensors support higher spatial resolution, higher bandwidth, and less susceptibility to noise compared to sensors placed on the scalp, and presumably have less clinical risk and stability problems than electrodes implanted within the brain. This development and validation effort promises to lead to more powerful but yet clinically practical BCI systems.
Gerwin coauthored A brain-computer interface using electrocorticographic signals in humans, EEG-based communication: presence of an error potential, The Interaction of a New Motor Skill and an Old One: H-Reflex Conditioning and Locomotion in Rats, Electrocorticography-Based Brain Computer Interface The Seattle Experience, Temporal transformation of multiunit activity improves identification of single motor units, The BCI Competition 2003: Progress and Perspectives in Detection and Discrimination of EEG Single Trials, and Spectral Changes in Cortical Surface Potentials during Motor Movement. Read the full list of his publications!
Gerwin earned his B.S. in Electrical Engineering and Computer Science at Graz University of Technology, Graz, Austria in 1995. He earned his M.S. in Electrical Engineering and Computer Science (Application area: medical informatics with a focus on image processing and artificial intelligence) at Graz University of Technology, Graz, Austria in 1999. He earned another M.S. in Information Technology (Application area: eBusiness) at Rensselaer Polytechnic Institute; Troy, NY, USA in 2001. He earned his Ph.D. in Computer and Systems Engineering at Rensselaer Polytechnic Institute; Troy, NY, USA in 2006. He holds the patent Brain computer interface.