Neurotransmitters: These are chemical messengers that transmit signals between neurons. They play a crucial role in how drugs interact with the brain.
Receptors: These are proteins located on the surface of cells that receive chemical signals from neurotransmitters. Drugs can bind to these receptors and either activate or block their function.
Dopamine: This is a neurotransmitter associated with pleasure and reward. Many drugs, such as cocaine or opioids, increase dopamine levels in the brain, leading to feelings of euphoria.