Definition:
Neurotransmitters are chemicals released from nerve cells in the brain that transmit information to other cells known as receptors. Neurotransmitters may be excitatory (stimulate receptor cells) or inhibitory (inhibit receptor cells). Neurotransmitters such as serotonin are excitatory, while others such as gamma butyric acid (GABA) are inhibitory. Many psychiatric disorders, such as social anxiety disorder (SAD), are believed to be partly the result of abnormalities related to neurotransmitters and receptors in the brain.
