RT Book, Section A1 Simon, Roger P. A1 Aminoff, Michael J. A1 Greenberg, David A. SR Print(0) ID 1148739152 T1 Coma T2 Clinical Neurology, 10e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9781259861727 LK neurology.mhmedical.com/content.aspx?aid=1148739152 RD 2023/12/01 AB Coma is a sleep-like state with no purposeful response to the environment and from which the patient cannot be aroused. The eyes are closed and do not open spontaneously. The patient does not speak, and there is no purposeful movement of the face or limbs. Verbal stimulation produces no response. Painful stimulation may produce no response or nonpurposeful reflex movements mediated through spinal cord or brainstem pathways. Coma results from a disturbance in the function of the brainstem reticular activating system above the mid pons or of both cerebral hemispheres (Figure 3-1).