Time blindness isn't carelessness — it's a difference in how the ADHD brain estimates duration and holds a mental timeline, tied to prefrontal and cerebellar circuits that track time. Two hours and twenty minutes can feel identical from the inside until a clock intervenes.

Interval timing — your brain's ability to sense 'how long has this been' — relies heavily on the cerebellum working together with dopamine-rich circuits in the basal ganglia. When dopamine signaling is less consistent, that internal stopwatch runs unevenly: sometimes fast, sometimes slow, rarely accurate.