There are aspects of cognition that are vaguely reminiscent of markets within an economy. For example, there is specialization as well as integration within both brains and economies. One of the problems posed by specialization is how the output of the specialized module or function can be integrated seamlessly with the whole, and this is one place where economics has an answer: through the price system. (An analogue in the brain could be the amount of secretion of a neurotransmitter or growth factor.) However, economies are made up of agents with self-interest.
Is it too far a stretch to think that neurons may be self-interested in a similar way? To justify the reasoning a little bit in biological terms, neurons are eukaryotic cells. There are a host of single-celled eukaryotic animals in the wild. These animals need to function in a self-interested manner, or else they wouldn't survive. Could neurons, therefore, have co-opted the self-interested "outlook" of such animals? After all, the basic DNA may still be there, right?