Methodological considerations in the neuropsychological study of central nervous system underarousal with a specific emphasis on coma

Several obstacles exist that impede the scientific study of pathological underarousal (stupor and coma). For instance, there is a lack of a clear, rational, standardized taxonomy with which to describe the phenomenon. Moreover, there is considerable confusion of the construct of arousal with other neurobehavioral constructs. The field also suffers from a general lack of acceptably reliable and valid instruments, especially measures of long-term outcome. Additionally, current treatments for chronic pathological underarousal are frequently presumptive and applied haphazardly, and thus do little to elucidate the process of recovery. It is suggested that biomedical and neuropsychological approaches to the study and treatment of pathological underarousal are complementary and that it is useful to view pathological underarousal as a behavioral, as well as a medical, phenomenon.