After hearing about Alex the African Gray Parrot, and knowing how intelligent ravens are, just how smart could a brain of that size become?
I would like to limit the responses to current known or theoretical science in order to have as much realism as possible, despite the fact that this would be for a decidedly non-human race (about the size and dimensions of a pygmy gibbon). I'm also referring to biological brains only, naturally evolved.
By max capacity I mean intelligence we could expect. It might be easiest to make educated guesses in the form of "IQ". If you have a better understanding of cell structure of the brain, number of cells that could exist in what density, etc. then I'd love to hear about that too.