A concussion is a traumatic brain injury that affects your brain function. Effects are usually temporary. After a bump on the head, look for signs such as headache, sensitivity to light, eye pain or fatigue, neck pain or stiffness, imbalance, impaired depth perception, difficulty remembering things, or changes in sleep patterns. If you’re experiencing these symptoms or if you simply have the sense that you’re not okay, consult a doctor for a complete assessment. Seeing your doctor early will give them the ability to tailor a treatment plan to your symptoms if you are diagnosed with a concussion.