Auditory stimulation effect on a comatose survivor of traumatic brain injury

The purposes of this case study were (1) to determine whether a comatose patient responded differentially to four types of auditory stimuli--voices of family members and friends, classical music, popular music, and nature sounds--and (2) to determine what physiological measures and behavioral observations best captured changes in responsiveness. The patient participated in 28 sessions that were videotaped for later behavioral analysis. During all sessions, measures were taken of pulse rate, respiration rate, and skin resistance. Visual inspection of the data and Auto Regressive Integrated Moving Average (ARIMA) analyses revealed greater increases in responsiveness with the presentation of taped voices of family and friends than with other types of taped stimuli. Behavioral observations of body movements and measures of pulse rate were superior to observations of facial expressions and measures of respiration rate and galvanic skin response in revealing changes in responsiveness. Despite extreme diversity among comatose persons, the research findings support the contention that responses to various auditory stimuli differ and are measurable with relatively simple behavioral and physiological observations.