Learn more about what happens to the brain in a car crash.
Bird's-Eye View Animation of a Mild Traumatic Brain Injury in a Car Crash
In addition to the deceleration forces, rotational forces are typically involved in most collisions. The combination of rotational and deceleration forces results in traumatic forces on the brain that may be far greater than the force of the collision may imply. This combination of forces is very similar to combining cold temperatures with high winds. Either alone may be tolerable, but when temperatures of 30 degrees are combined with winds of 30 miles per hour, the net effect can be quite chilling. When the skull and brain are viewed and sectioned from above, it can be seen that the brain consists of two halves that are connected by only a few central structures. One of these structures is called the corpus callosum. The corpus callosum consists of axons that allow for communication between the opposite sides of the brain. The front of the corpus callosum is called the genu. The two halves of the brain are separated by a tough ligamentous structure called the falx. The falx is rigidly fixed to the skull in the front, back, top, and bottom of the skull. [Corpus Callosum Injury During Sudden Deceleration and Rotation] During the violence of an impact involving the combined sudden deceleration and rotational forces, similar to the one shown in earlier animation sequences, the corpus callosum can often become injured. The injuries occur because the soft, friable brain reacts in a very fluid-like way as a result of the violent forces. The left side of the brain impacts against the falx, and the right side of the brain pulls away from the falx. Because the falx is rigid, the axons that comprise the corpus callosum are torn and broken. Again, thousands of axons may be torn without being evident on imaging studies.
Posted on BrainLine December 15, 2008.