Dopamine is a substance secreted by the brain that can affect a person’s mood. Dopamine won the 2000 Nobel Prize in Medicine for its role as a message transmitter in the brain. Dopamine is a neurotransmitter, a chemical used to help cells transmit impulses, and is primarily responsible for the brain’s lust, sensations, and the transmission of excitement and happy messages, and is also associated with addiction. Love is actually the result of the production of large amounts of dopamine in the brain, so smoking and drug use can increase the production of dopamine, making people addicted to feel happy and excited. According to research, dopamine can treat depression, while insufficient dopamine levels can cause loss of muscle control, involuntary shaking of the arms and legs, or Parkinson’s syndrome. Scientists have recently shown that dopamine can be used to treat Parkinson’s disease.