Opponent control of reinforcement by striatal dopamine and serotonin

I presented this paper in our lab's journal club and we found the results both interesting but a bit confusing. The choice of focusing on the posterior medial shell of the nucleus accumbens makes sense based on the tracing data, but given the lack of canonical dopaminergic responses in this region, it seems redundant to focus on reward/associative learning. Further, there are some details that I couldn't find justifications for: for example, why did they conduct DR retrograde tracing in the first experiment by injecting Ctb in different brain regions rather than different subregions of the NAc (like they do later in the study)? A few of the behavioural paradigms used were confusing (the optogenetic conditioning paradigm could have been better explained, for example) and I'm not sure how well paradigms like the real-time place preference test used to distinguish between reward learning and reinforcement (Fig 3 I think) actually did what they intended to do. Overall, I think the finding of inverse dopamine and serotonin activity simultaneously is incredibly cool, but these experiments need to be developed a lot more in terms of the behaviours they study and the brain areas they target.

0

0