Made of gelatinous neural mass; soft tofu (very squishy) Anchors itself at sutures (where bones greenish layer under gray. Makes a 1500 g brain into a functional mass of 50 g. Direct blow to head, face or neck, or elsewhere on the body with impulsive force transmitted to head. Impact direct impact to the head mechanism. Impulse-inertial hit somewhere else on the body (usually trunk), which causes a whiplash-like momentum. Biomechanics #2: brain is not a free floating mass, it is like a ball anchored at the bottom. Concussions result from the angular acceleration of the brain (sort of like flexion and extension) and not from shifting linearly back and forth. Vascular, neural, dural tissues tether it to the front of the base of the skull: brain rotates around its anchor point (like tether ball). Biomechanics #3: tension (strain) and compression (pressure) Coup countercoup phenomenon; tension and compression caused concussion.