My mind was a blank and I couldn't remember her name.

我脑子里是一片空白，记不起她的名字了。

《牛津词典》

I'm sorry, but my mind is a blank.

很抱歉，可是我脑子里一片空白。

《柯林斯英汉双解大词典》

Suddenly, my mind was blank.

突然地，我脑中一片空白。

youdao

My mind went blank.

BBC: Indian parliament attack kills 12

In a "busy" environment, I will eventually go into sensory overload and my mind will go blank.

CNN: Asperger's: My life as an Earthbound alien

Ms. PROSE: Historical fiction in the first person - I mean my mind is now going blank.

NPR: Could You Be the Great American Novelist?