The Digester

Dopamine explains the 'skip in your step' when you get a reward

Feb 28th 2026

A CU Boulder study shows that unexpected rewards produce a rapid dopamine-linked boost in movement vigor during a simple reaching task, a finding that could inform research on Parkinson's, depression and other movement-related conditions.

  • CU Boulder engineers Alaa Ahmed and Colin Korbisch published the study Feb. 27 in Science Advances based on a joystick reaching task.
  • Unexpected rewards produced a measurable speeding of reaches about 220 milliseconds after the beep.
  • When an outcome was certain, subjects showed no secondary increase in movement vigor after the reward.
  • Repeated rewards made subjects move faster overall, while repeated non-rewards made them slower.
  • The movement patterns mirror dopaminergic reward prediction error signals, implicating dopamine in quick changes to movement vigor.
  • The results could help scientists track or diagnose conditions that alter movement, including Parkinson's disease and depression.

Sources

colorado.edu