他在遭受失去记忆的痛苦。

He was suffering from the loss of the memories.

youdao

他的病使他失去了记忆。

His illness caused him to lose his memory.

《柯林斯英汉双解大词典》

你失去了你的记忆。

You lose your memory.

youdao

And I forget where Napoleon actually dies, but he's got memories of getting sick and ill and the light begins to fade and he goes unconscious.

我不记得拿破仑在哪里去世了，但他有生病的记忆,生命之光慢慢变弱，然后失去了意识。

耶鲁公开课 - 死亡课程节选

I may lose some of my previous beliefs,lose some of my previous memories, but that's okay as long as it's a slowly-evolving personality with enough overlap.

也许会失去先前一些信仰和记忆，只要这是相似度够高的缓慢进化就可以了。

耶鲁公开课 - 死亡课程节选