What is the term for a temporary loss or alteration of brain function without actual physical damage to the brain?

The term that refers to a temporary loss or alteration of brain function without any actual physical damage to the brain is a concussion. A concussion is classified as a mild traumatic brain injury that results from a blow to the head or a sudden jolt to the body, which causes the brain to move rapidly back and forth within the skull. This movement can lead to chemical changes in the brain and disrupt normal brain function, leading to symptoms such as confusion, headaches, dizziness, and memory disturbances.

In the context of other options, while coma is a state of prolonged unconsciousness and syncope refers to a temporary loss of consciousness due to a drop in blood flow to the brain, these conditions are more severe and involve actual clinical implications beyond altered function. Aphasia, on the other hand, specifically describes a language disorder that affects a person's ability to communicate, which is different from the overall functional alterations seen in a concussion. Thus, concussion is the appropriate term to use in this scenario.