RT Book, Section
A1 Brust, John C. M. 
SR Print(0)
ID 1180669405
T1 Examination of the Comatose Patient
T2 Practice of Neural Science: A Case-Based Approach
YR 1
FD 1
PB 
PP New York, NY
SN 9781264258956
LK neurology.mhmedical.com/content.aspx?aid=1180669405
RD 2024/04/19
AB Consciousness  is  awareness  of  oneself  and  one’s  environment;  it  requires  both  arousal  and  mental  content.  The  anatomic  substrate  for  arousal  is  the  reticular  activating  system  of  the  brain  stem  and  thalamus;  the  anatomic  substrate  for  mental  content  is  the  cerebrum.  Impaired  consciousness  thus  follows  either  small  brain  stem  lesions  or  large  bilateral  cerebral  lesions.  Temporary  loss  of  consciousness  can  follow  sudden  severe  lesions  within  a  single  cerebral  hemisphere,  for  example,  intracerebral  hemorrhage.  The  mechanism  is  a  poorly  understood  transsynaptic  functional  suppression  of  the  opposite  hemisphere  referred  to  as  diaschisis  and  reflected  in  decreased  blood  flow,  oxygen  uptake,  and  glucose  metabolism.  Prolonged  or  permanent  loss  of  consciousness,  however,  indicates  damage—structural  or  metabolic—either  to  the  cerebral  hemispheres  bilaterally  or  to  the  reticular  activating  system.