lost and blank


I have a question on the sentences below:

I’m sorry, professor, but I’m blank. Would you be so kind as to rephrase the question? Maybe that’ll help my memory.

Here, the speaker seems to be daydreaming while the professor is teaching. Am I right in understanding this?

He’s got blue eyes and curly hair. He also looks permanently lost. I’m sure you’ll recognise him.

look permanently lost – does it mean it seems like that he lost his sight? Or he seems dazed or blank? I’m curious.

Thank you in advance,

To me, it means something like this:

You will have no trouble recognizing him. He has blue eyes and curly hair. He also always appears as if he doesn’t know where he is. His facial expression shouts: “Where am I?”

Hi, your first sentence sounds a little off to me. I think the speaker means “drawing a blank” idioms.thefreedictionary.com/draw+a+blank

He asks the professor to rephrase the question, not repeat it. And he says the problem is his memory, not that he wasn’t paying attention. These seem to imply he doesn’t know the answer, not that he was daydreaming.