Quick search Find article
Quick search
Find article

Using human extra-cortical local field potentials to control a switch*

Philip Kennedy1, Dinal Andreasen1,2, Princewill Ehirim3, Brandon King4, Todd Kirby5, Hui Mao6 and Melody Moore7

Show affiliations


Individuals with profound paralysis and mutism require a communication channel. Traditional assistive technology devices eventually fail, especially in the case of amyotrophic lateral sclerosis (ALS) subjects who gradually become totally locked-in. A direct brain-to-computer interface that provides switch functions can provide a direct communication channel to the external world. Electroencephalographic (EEG) signals recorded from scalp electrodes are significantly degraded due to skull and scalp attenuation and ambient noise. The present system using conductive skull screws allows more reliable access to cortical local field potentials (LFPs) without entering the brain itself. We describe an almost locked-in human subject with ALS who activated a switch using online time domain detection techniques. Frequency domain analysis of his LFP activity demonstrates this to be an alternative method of detecting switch activation intentions. With this brain communicator system it is reasonable to expect that locked-in, but cognitively intact, humans will always be able to communicate.


Footnote
*  Financial disclosure. Authors PK and DA may derive some financial gain from the sale of this device. A patent has been applied under US and international law: 10/675,703.
PACS

87.19.X- Diseases

87.19.R- Mechanical and electrical properties of tissues and organs

87.19.L- Neuroscience

87.85.Ng Biological signal processing

Subjects

Medical physics

Biological physics

Dates

Issue 2 (June 2004)

Received 16 March 2004, accepted for publication 19 May 2004

Published 14 June 2004



View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.