How to Catch Brain Waves in a Net
From: IEEE Spectrum - 08/21/2014
By: Nitish V. Thakor

A mesh of electrodes draped over the cortex could be the future of
brain-machine interfaces

Last year, an epilepsy patient awaiting brain surgery at the renowned Johns
Hopkins Hospital occupied her time with an unusual activity. While doctors
and neuroscientists clustered around, she repeatedly reached toward a video
screen, which showed a small orange ball on a table. As she extended her
hand, a robotic arm across the room also reached forward and grasped the
actual orange ball on the actual table. In terms of robotics, this was
nothing fancy. What made the accomplishment remarkable was that the woman was
controlling the mechanical limb with her brain waves.

The patient had a mesh of electrodes inserted beneath her skull and draped
over the surface of her brain. These electrodes produced an
electrocorticogram (ECoG), a record of her brain’s activity.

ECoG systems provide a better signal-to-noise ratio than EEG, and the data
includes high-frequency components that EEG can’t easily capture. ECoG
systems also do a better job of extracting the most useful information from
the brain, as an electrode placed over the motor cortex can specifically
listen in on the electrical activity most relevant for controlling a
prosthetic arm. Similarly, electrodes draped over the brain areas associated
with speech can capture signals associated with verbal communication.

Read the entire article at:
http://spectrum.ieee.org/biomedical/bionics/how-to-catch-brain-waves-in-a-net

Links:
Nathan Crone
http://www.hopkinsmedicine.org/profiles/results/directory/profile/0006037/nathan-crone

Johns Hopkins University Neuroengineering Lab
http://web1.johnshopkins.edu/nthakor/