From: goetz@cs.buffalo.edu (Phil Goetz)
Subject: Re: LEGAL: Epilepsy health warnings
Date: Mon, 8 Feb 1993 16:34:41 GMT
Organization: State University of New York at Buffalo/Comp Sci



In article <1jvoevINNkgv@shelley.u.washington.edu>
diego@minerva.st.dsi.unimi.it (Diego Montefusco) writes:

>I recall that everyone suffering from epilepsy has some kind of "critical"
>frequency, which (if I recall right) is the one her/his brain works at when
>having a crisis (sp?). If s/he gets a visual stimulation at the frequency,
>like when driving in a straight road with trees on the sides and the sun
>appearing and disappearing through the trees, an epileptic attack can be
>induced.

The worst frequency is around 10 Hz.  This is the frequency of the
alpha rhythm, if I recall correctly, which basically takes over the
brain in an epilectic fit.  Visual stimulation is mapped fairly
directly onto visual cortex in Brodmann's area 17, so it can set up a
wave.  So avoid 10Hz.

Why can't we stop fits with implanted electrodes that sense and break
up large 10Hz alpha rhythms?

Phil
goetz@cs.buffalo.edu