Final answer:
Yes, a head injury with sufficient force can cause a bruise on the brain, typically known as a concussion, which can lead to various temporary problems and requires medical attention despite often healing on its own.
Step-by-step explanation:
A head injury of sufficient force can indeed bruise the brain, which is typically referred to as a concussion. This type of injury is common in sports and can lead to temporary problems like headache, drowsiness, and confusion that are symptomatic of the brain's response to trauma. While concussions often heal on their own within a few days, they should still be taken seriously and monitored for any signs of complication. More severe brain injuries can result from stronger impacts to the skull, potentially causing fractures and bleeding within the skull that put pressure on the brain. Symptoms of severe brain injuries vary but can include profound confusion and loss of consciousness. Any severe head impact requires immediate medical attention due to risks such as hematoma, permanent damage, and even life-threatening complications.