He says he has amnesia and can't remember his name.他说他有健忘症, 记不住他的名字。

It could have happened when he was suffering from amnesia.那可能是在他得遗忘症时发生的。

the Opposition's selective amnesia about their own record when in power在野党对自身过去执政记录的选择性遗忘

The huge support in opinion polls for military action indicates a collective amnesia of our moral tradition.民意调查中对军事行动的巨大支持显示出我们对道德传统的集体失忆。