Retrograde amnesia can be caused by Alzheimer's disease, traumatic brain injury (ask an NFL player), thiamine deficiency or other insults.

逆忘式健忘症可由阿尔茨海默氏症、脑部重创、硫胺素缺乏等造成。

youdao

He suffered seizures following the assault and was found to have post traumatic amnesia.

BBC: South Bridge, Edinburgh

Psychologist Richard Samuels testified for the defense that Arias suffered from post-traumatic stress disorder and dissociative amnesia, which explained why she couldn't recall much from the day of the killing.

NPR: Jodi Arias Convicted Of First-Degree Murder