A new study is changing our understanding of dopamine's role in the brain. Scientists have found that dopamine does not function as the brain's "gas pedal" to determine the speed or force of movement. Instead, dopamine functions much like the oil in an engine - it allows movement in the background and maintains basic functions. When the researchers manipulated dopamine levels during movement, nothing about the movement changed. However, restoring baseline dopamine levels had a significant effect. This finding could change the approach to treating Parkinson's disease, as it suggests that treatment should focus on maintaining stable dopamine levels instead of increasing them during movement.