In addition to monitoring levels of consciousness, the study also tested the ability of the participants’ brains to process sounds that were not words. The participants were played a series of unpleasant sounds both while awake and while under general anesthesia. The results of the EEG demonstrated that brains react more quickly to familiar sounds, even if unpleasant. This pattern was consistent for unpleasant sounds that were played for study participants while under general anesthesia. Essentially, participants reacted more quickly to the sounds that were more familiar.
Previous studies have allowed researchers to monitor changes in brain waves that match changes in consciousness. This study, due to the close monitoring and specificity of the drugs administered, allowed researchers to identify changes in the brain due to drugs and changes that were a direct result of changing states of consciousness. This study confirms the previously suggested theory that anesthesia doesn’t turn off the brain; rather it prevents certain parts of the brain from communicating freely.