Our sense of time is far from constant. For example, time flies when we’re having fun , and in retreat, when we’re bored. Dopaminergic neurons in the midbrain have been implicated in variable time estimation. However, a direct link between the signals carried by dopamine neurons and temporal judgments is missing.
We measured and manipulated the activity of dopamine neurons and how rats judged the length of time intervals. We found that pharmacogenetic suppression of dopaminergic neurons caused a decrease in behavioral sensitivity to time and that dopamine neurons encoded information about the variability judgment in time estimates.
Finally, it was found that the transient activation or inhibition of dopamine neurons was sufficient to delay or accelerate the time estimate, respectively. The activity of dopamine neurons thus reflects and can directly control the judgment of time . ”