Brain Concussion

Brain concussion (from Latin concussio — shaking, concussion) is the most common and mild form of traumatic brain injury, characterized by a transient disturbance of nervous system functions without visible macroscopic damage to brain tissue.

Etiology and pathophysiology

The pathogenesis is based not on structural but exclusively on functional and microscopic damage to nerve cells. The mechanism of injury typically involves rapid acceleration, deceleration, or rotation of the head (for example, during falls, impacts, or traffic accidents).

A false neurometabolic cascade is triggered at the cellular level. Neuronal cell membranes temporarily stretch, leading to a chaotic release of potassium ions outside and a massive influx of calcium into the cell. An acute energy crisis develops: the brain requires a lot of glucose to restore balance, but capillary spasm critically reduces its delivery. This temporary ‘energy starvation’ of cells accounts for the symptoms.

Clinical significance

The clinical presentation manifests immediately after impact. Classical signs include brief loss of consciousness (lasting several seconds to several minutes), stupor, severe headache, nausea, and single vomiting. An extremely specific symptom is amnesia — the patient cannot remember events directly leading up to the injury or occurring immediately after it.

The diagnosis is based on clinical symptoms. Standard computer or magnetic resonance scans do not reveal any hemorrhages, swelling, or fractures in cases of pure concussion. The treatment is conservative, based on strict cognitive and physical rest (limiting screen use, reading, and activity) to allow the brain time to recover its energy balance.