You could say he's receptive - able or quick to receive knowledge, ideas, etc.: a receptive mind.

But if he's exceptionally so, maybe hyper-receptive (hyphenated or not), but this can have negative connotations, particularly in medical contexts.

You could say he's receptive - able or quick to receive knowledge, ideas, etc.: a receptive mind.

If he's exceptionally so, maybe hyper-receptive (hyphenated or not). But this can have negative connotations, particularly in medical contexts.