From: david gobel (davegobel@erols.com)
Date: Thu Feb 11 1999 - 17:31:48 MST
the mind boggles...the world turns...dave gobel
Exp Brain Res 1999 Jan;124(2):223-32
The thought translation device: a neurophysiological approach to
communication in total motor paralysis.
Kubler A, Kotchoubey B, Hinterberger T, Ghanayim N, Perelmouter J, Schauer
M, Fritsch C, Taub E, Birbaumer N
Institute of Medical Psychology and Behavioral Neurobiology, University of
Tubingen, Germany.
[Medline record in process]
A thought translation device (TTD) for brain-computer communication is
described. Three patients diagnosed with amyotrophic lateral sclerosis
(ALS), with total motor paralysis, were trained for several months. In order
to enable such patients to communicate without any motor activity, a
technique was developed where subjects learn to control their slow cortical
potentials (SCP) in a 2-s rhythm, producing either cortical negativity or
positivity according to the task requirement. SCP differences between a
baseline interval and an active control interval are transformed into
vertical or horizontal cursor movements on a computer screen. Learning SCP
self regulation followed an operant-conditioning paradigm with
individualized shaping procedures. After prolonged training over more than
100 sessions, all patients achieved self-control, leading to a 70-80%
accuracy for two patients. The learned cortical skill enabled the patients
to select letters or words in a language-supporting program (LSP) developed
for inter-personal communication. The results demonstrate that the fast and
stable SCP self-control can be achieved with operant training and without
mediation of any muscle activity. The acquired skill allows communication
even in total locked-in states.
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 15:03:02 MST