Dopamine in the striatum of the brain is critical to the selection and learning of our motivated actions. Dopamine neurons input into a system called the basal ganglia which regulates our voluntary actions and helps us to respond particularly to something we perceive as having a benefit or rewarding property, and consequently carrying motivational value. Dopamine helps us select actions and learn from the associations we make between a stimulus, our action and its outcome, to change the way we might respond next time.
A new paper from Department of Physiology, Anatomy & Genetics (DPAG), published in Nature Communications, has managed to uncover some surprising observations on this unusual neuronal network. Unlike for many other types of synapses in the brain, the team has found that the short-term plasticity in dopamine release is not very sensitive to calcium and initial release probability. Instead, it shows a form of release-insensitive depression. By detecting dopamine and imaging calcium in axons, results suggest that the critical mechanisms are those that shape the ability to depolarise or repolarise axons.
Read more (DPAG website)