Um, I wrote the article based upon a loose sense of what was going on, so the link with displacement activity may be from me or from someone else. The link to TDL is me—it may or may not be true, but it seems like a likely candidate for the mechanism in operation. For example, read the wikipedia article on TD Learning :
Dopamine cells appear to behave in a similar manner. In one experiment measurements of dopamine cells were made while training a monkey to associate a stimulus with the reward of juice.[4] Initially the dopamine cells increased firing rates when exposed to the juice, indicating a difference in expected and actual rewards. Over time this increase in firing back propagated to the earliest reliable stimulus for the reward. Once the monkey was fully trained, there was no increase in firing rate upon presentation of the predicted reward. This mimics closely how the error function in TD is used for reinforcement learning.
Um, I wrote the article based upon a loose sense of what was going on, so the link with displacement activity may be from me or from someone else. The link to TDL is me—it may or may not be true, but it seems like a likely candidate for the mechanism in operation. For example, read the wikipedia article on TD Learning :