Brain Concussion Theories
There exist two commonly accepted theories to explain brain concussion. According to shear-strain theory (e.g., Holbourn, 1943), the brain damage is mainly due to the high shear strains in the brain tissue caused by rotational acceleration and relative motion between the brain and the skull. On the other hand, according to cavitation theory (e.g., Gross, 1958), the brain tissue damage is caused by the sudden collapse of small bubbles that appear on the opposite location of the impact (see below). These bubbles are generated as consequence of the negative pressure developed due to the translational acceleration of the brain. This mechanism, combined with the deformation and posterior restitution of the skull results in cavitations that extend to all of the brain mass.
Cavitation at the opposite side of the impact due to a intense low pressure in the intracranial fluid
(from Gross, 1958)
