They come late to appointments and have trouble keeping rapidly moving events in proper chronological order. A study in the Feb. 7 issue of the British medical journal The Lancet found that people with attention deficit hyperactivity disorder tend to have smaller than normal frontal lobes and basal ganglia, the loop that Meck and his colleagues think is the interval time keeper. Abnormalities in the clock might explain inattentive, hyperactive, impulsive behavior. People with Huntington's disease lose the spiny neurons in the striatum and experience uncontrolled, dancelike movements. They also have problems with time perception.
Researchers agree that drugs affect the brain's sense of time.
Cocaine and methamphetamine both increase the amount of dopamine and speed up the interval clock or its equivalent elsewhere in the brain. A similar chemical cascade may happen during an accident, when dopamine and other neurotransmitters flood the brain, Mangan said. Time seems to stand still or move incredibly slowly. Conversely, drugs that reduce the amount of dopamine in the brain, like Haloperidol and Clozapine, used to treat schizophrenia, and marijuana, slow the interval clock, Meck said. It is in growing older that most people will experience the vagaries of the interval clock.