According to the Mayo Clinic, common symptoms of a brain injury may include:Loss of consciousnessHeadacheNauseaFatigue, sleepinessSleeping too muchDizzinessSpeech problemsVision problems including sensitivity to lightMemory lossDepressionMood changesSigns of a severe brain injury include those above, as well as:ComaSeizuresPupil dilationClear fluid from nose or earsInability to wake upNumbness in extremitiesCombativeness and unusual behaviorSymptoms of brain injuries in children can be tougher to spot, in part because a child can’t always express what is wrong in the same way that an adult can. Symptoms may include changes in eating or nursing habits, lack of interest in toys/playtime, personality and behavioral changes, as well as any of the symptoms noted for adults.If you or someone you know is experiencing or has experienced any of the symptoms listed above, or any other unusual behavior following a head injury, proceed immediately to the emergency room for medical treatment.