what is transient global a
home / medterms medical dictionary a-z list / transient global amnesia definition Medical Definition of Transient global amnesia Transient global amnesia: A passing episode of short-term memory loss without other signs or symptoms of neurological impairment. In transient global amnesia (TGA) the individual does not lose consciousness but does lose the ability to form new lasting memories. Motor function is not affected. The individual may be disoriented to place and time, may recognize that something is wrong, and may become distressed at this realization.