The Influence of Visual and Auditory Stimuli on the Electroencephalographic Tracing of Petit Mal

Light stimuli affect the alpha rhythm according to the "all or none" law. 2. Light stimuli have a delayed reaction time in short petit-mal attacks. 3. Light stimuli are not perceived in long petit-mal attacks. 4. Both light and sound stimuli tend to terminate moderately severe petit-mal seizures-the sound being much more effective. 5. When both fail to provoke a response, unconsciousness may be presumed. 6. This method of determining the impairment of consciousness may be useful in: (a) Estimating the severity of petit-mal seizures. (b) The effectiveness of anticonvulsant therapy on the spells.