Opponent Interactions between Serotonin and Dopamine
Nathaniel D Daw Sham Kakade Peter Dayan
Neural Networks 15, 603-616.
Abstract
There is suggestive evidence that the dorsal raphe serotonin system
and the ventral tegmental and substantia nigra dopamine system can
act as mutual opponents. In the light of the temporal difference
model of the involvement of the dopamine system in reward learning,
we consider three aspects of motivational opponency involving
dopamine and serotonin. We suggest that a tonic serotonergic signal
reports the long-run average reward rate as part of an average-case
reinforcement learning model; that a tonic dopaminergic signal
reports the long-run average punishment rate in a similar context;
and finally speculate that a phasic serotonin signal might report an
ongoing prediction error for future punishment.
pdf