Electrocorticography (ECoG) neural interfaces are devices currently used to pinpoint the source of epileptic seizures. Placed directly on the surface of the brain, they can read the brain’s electric signals for external processing. Researchers from Washington University School of Medicine in St. Louis and the Wadsworth Center in Albany, NY are working on miniaturizing electrocorticography devices to make them smaller and implantable under the scalp for many years. Working with Neurolutions, a St. Louis startup, the developers hope to create a system that can control prosthetic devices, wheelchairs, and computers by paralyzed folks.
From MIT Tech Review:
Most efforts to build neural interfaces have focused on either electroencephalography (EEG), a noninvasive technology that records electrical activity from the scalp, or electrodes implanted into the brain. ECoG represents an intermediate between the two: because it records directly from the brain, it can provide a higher level of control than EEG, which is susceptible to distortion as the signal travels through the skull and as the patient moves. In addition, ECoG’s position on the surface of the brain may present fewer health issues than electrodes that penetrate brain tissue.
Because ECoG is used in epilepsy patients, researchers have already been able to conduct proof of principle experiments on a much wider scale than has been done using other invasive technologies. Tests of more than 20 patients have shown that people can quickly learn to move a cursor on a computer screen using their brain activity. Researchers first ask patients to imagine performing a certain action, such as moving a computer cursor to the left. They then identify changes in the frequency of electrical signals that correlate with that movement and use those to control the computer. The patient learns to more precisely control his or her brain activity and hence more reliably performs the task within half an hour.
Read on at MIT Technology Review…
Image credit: Eric Leuthardt, Washington University School of Medicine