Head injuries constitute a major percentage of the cases of trauma admitted to a children's hospital. Over a period of four years, from January, 1954, to December, 1958, 2,200 cases with a diagnosis of craniocerebral injury were admitted to the neurosurgical service at the Hospital for Sick Children in Toronto. Many of these cases were severely injured, and were admitted in a state of decerebrate rigidity. Decerebrate rigidity in humans from varied causes has always been associated with a more or less hopeless prognosis. The signs of profound unconsciousness, with associated exterior rigidity in the extremities, plus bilateral plantar extensor responses and pinpoint pupils indicate a severe lesion at the midbrain. Many authors have pointed out that there may also be associated signs of injury to the hypothalamus, producing the symptoms of sham rage, diabetes insipidus, loss of thermal control, personality changes, as well as changes in the control of