Experimental head impact and whiplash injury experiments have been conducted in 3 sub-human primate species in order to define tolerance thresholds for onset of cerebral concussion. Preliminary analysis of our data support a hypothesis that approximately half of the potential for brain injury during impact to the unprotected movable head is related to head rotation, the remaining brain injury potential of the blow is related to the contact phenomena of the impact.

Data derived in these experiments is compared with values predicted from some scaling considerations previously developed. Predictions are made that the levels of head rotation during whiplash, in excess of 1800 rad./sec², will probably result in cerebral concussion in man.