Effects of auditory stimuli on comatose patients with head injury

This descriptive study was a pilot effort to determine the effect of specific sensory input on the cortical activity of a selected population of young adults with a closed head injury. The specific research questions were (1) Does the comatose patient demonstrate a response on an electroencephalogram (EEG) to a specific auditory stimulus? (2) Does the comatose patient demonstrate other types of responses to a specific auditory stimulus? The subjects were three male and two female young adults 15 to 29 years of age who had a closed head injury as the result of an automobile accident. A similarity in depth of coma was established by using the Glasgow Coma Scale. Cortical activity was recorded by EEG at the same time that auditory stimulation was introduced to the subject. Data obtained by observation during the period of EEG recording were also included by an additional measure of the subject's response to stimulation. The findings indicate that persons in a coma do respond to auditory stimulation. The responses were varied in this small sample, but some type of response did occur. Two patients demonstrated a response on EEG and the other responded by eye opening or extremity movement. The EEG alone does not appear to be useful as a measure of response to auditory stimulus. Further work needs to be done to determine what other methods measure the response of comatose patients to auditory stimulation.