Final answer:
A serious head injury with symptoms such as loss of consciousness, amnesia, or seizures is referred to as a Traumatic brain injury (TBI).
Step-by-step explanation:
The term that denotes a serious head injury characterized by one or more of the following: loss of consciousness, amnesia, seizures, or a change in mental status is Traumatic brain injury (TBI). A concussion, while it can be serious, is typically less severe and usually results in temporary symptoms. However, repeated concussions can lead to lasting problems. TBIs can result from various types of impacts to the head, and some of the symptoms include profound confusion and potential alterations in mental abilities such as memory. Serious TBIs may require treatments like medicines and counseling to aid in recovery or adaptation to any disabilities incurred from the injury.