Final answer:
Signs of head injury can appear immediately or take time to develop. Mild brain injuries may have symptoms within hours or days, while serious brain injuries may show signs like loss of consciousness, confusion, or trouble talking and moving.
Step-by-step explanation:
Signs of head injury can appear immediately after a blow to the head or may take some time to develop. For mild brain injuries like a concussion, symptoms may appear within a few hours or even days after the incident. These symptoms may include headache, drowsiness, confusion, and temporary problems.
On the other hand, for serious brain injuries that cause permanent damage, symptoms may include loss of consciousness, profound confusion, trouble talking or controlling body movements. The symptoms of a stroke, which is a type of brain injury, usually occur within seconds or minutes after the injury.
It is important to note that a single concussion is unlikely to cause permanent damage, but repeated concussions can lead to long-term difficulties.