ABSTRACT
Consciousness is a term that can be defined either in strictly medical terms, as in the differentiation between those who are comatose and unresponsive after head injury and those who have “emerged” from coma (Plum & Posner, 1980), or in more philosophical terms, such as references to wakefulness, awareness, knowledge etc. (e.g., Anthony, 1999). Cartlidge (2001) describes consciousness as being characterised by “an awareness of self and environment and an ability to respond to environmental factors” (p. 18). He further defines consciousness as having two components-arousal or wakefulness and awareness of self. However, consciousness is difficult to define in an “all or nothing” context-it is more appropriate to consider it as a continuum rather than a discrete event; that is, patients can progress or deteriorate from one “level” of consciousness to another sometimes. In the more acute stages after brain injury, i.e., during acute coma, this can occur several times a day.
