Occasional problem with my keyboard

I have an old MacBook Pro. Every once in a while, the keyboard isn't responsive--in that I'll press the letter and nothing happens. It usually is the top row of letters, mainly e-r-t-y-u-i-and o. If I tap it a bunch of times, it eventually works. And it seems to help if I blow really hard at the letters.

Is there anything I can do to resolve this? I'd rather not have to buy a new computer.