Dementia is a broad term used to describe a decline in cognitive ability, while amnesia is an impairment of memory caused by damage to certain areas of the brain. While both conditions have similar signs and symptoms, they are fundamentally different and require different treatments.

amnesia noun am· ne· sia am-ˈnē-zhə Synonyms of amnesia 1 : loss of memory due usually to brain injury, shock, fatigue, repression, or illness 2 : a gap in one's memory 3 : the selective overlooking or ignoring of events or acts that are not favorable or useful to one's purpose or position …

Transient global amnesia (TGA) is a clinical syndrome characterized by the acute onset of anterograde amnesia (the inability to form new memories) . Patients with TGA frequently ask repetitive questions reflecting disorientation and may have variable inability to recall general or personal information (retrograde amnesia) while the episode lasts.