Tuesday, July 12, 2011

Dopamine, reward, and beliefs

I want to point to comments made by Charles (The Dopamine Project) on the How we form beliefs post below. The Sapolsky video is quite entertaining.


  1. Well, if someone gets upset it would by most accounts be due to a relative absence of dopamine. More broadly though, I think the fact that dopamine seems to explain all these phenomena tells us more about the current state of neuroscience than it does about how these phenomena arise from neurotransmitter function. When all you've got is a hammer, everything looks like a nail. The reward prediction error framework is one big powerful hammer, and dopamine has become inextricably attached to it.

    But there are competing accounts - not only of dopamine serving possibly alternative roles, but of other neuromodulators participating in representing prediction errors. The serotonin aversion hypothesis is a great example (Daw, Dayan, et al).

    In the end I think it's important not to reify the reward prediction error hypothesis and to
    acknowledge that, in the final analysis, one might replace each of Charles' usages of dopamine with serotonin and also be correct.

    Function is probably distributed across neuromodulators just as much as it is across neurons.

  2. As one who's worked in the dopamine/reward area for 20 years (yikes! Has it really been that long?), I second Chris' view. It may be best, also to avoid a kind of 'neurochemical phrenology' -- i.e., looking for the transmitter that corresponds to 'wanting', 'liking'. Why not 'wistfulness' while we're at it. :)