The Doctor was still listening, but it took him a few moments to respond - he was working on a particularly delicate bit of the filter. In fact, he had what appeared to be a small key in his hand and he was holding it up to the light so that he could examine it.
Then it went back into his pocket. Yes, if he could keep Fred close enough, he should be able to extend the field to her. Link the sets of glasses and they'd be fine.
"It wouldn't be the first time someone had told stories about me." The Doctor commented, finally. The thought of being a story in someone else's time and place didn't bother him, or didn't appear to bother him. He barely glanced up, and it was the phrase 'those of us who are a little different' that got his attention.
"How're you different? You've human readings." Granted, she was exceptionally bright for a human, but that went without saying. "Human vital signs, human reactions to drugs."