Christopher D. Fiorillo, Korea Advanced Institute of Science and Technology
Science, vol 341, 2 August 2013
Summary of the above article
The study shows that while midbrain dopamine neurons are activated by evidence of reward, and suppressed by lack of reward, and are also capable of signalling prediction error relative to reward level, they are , however, not responsive to aversion.
This suggests that reward and aversion are represented independently. Dopamine neurons are thought to estimate evidence for and against reward in terms of excitation and inhibition. However, it is argued that aversion is not taken into account. The lack of response of dopamine neurons to aversion suggests that separate neurons are responsible for processing aversion. Neuromodulators other than dopamine are suggested to be involved.