ABSTRACT
Even after the most severe strokes there is some kind of recovery in those who do not immediately die. The most common sequence of events is coma followed by recovery to consciousness. The reasons that brain damage causes coma are not entirely known. Strokes that affect the cerebral hemispheres alone (supratentorial strokes) may not produce coma unless they cause massive damage. These strokes may produce paralysis or speech impairment against a background of clear consciousness while the patient struggles to carry on with normal activities. The emotion usually described in retrospect is that of being puzzled or bewildered. It is unusual for the patient to realize immediately that it is a stroke that has caused the perplexing disability. Strokes that affect the pons and brainstem are more likely to cause coma, presumably by specifically affecting the reticular activating system (Frank and Biller, 1992), but it is possible, as described earlier, for such strokes to present as states of confusion.
