Final answer:
Neurotransmitters are natural chemicals that pass messages between brain cells. Imbalances in neurotransmitter systems can lead to psychological disorders. Medications can restore neurotransmitter balance.
Step-by-step explanation:
Neurotransmitters are endogenous chemicals that enable neurotransmission. They are natural chemicals that pass messages between brain cells. When there are imbalances in neurotransmitter systems, it can lead to psychological disorders like depression and schizophrenia. Psychotropic medications can help improve symptoms by restoring neurotransmitter balance.