PSYC62H3 Chapter 5: chapter 5
Document Summary
Specific neuroactive ligands are highly localized in some areas of the brain, while others are distributed widely throughout the nervous system. By interacting with the natural neuroactive ligands in various areas of the brain, drugs can shift normal psychological activities carried out by the brain into abnormal ones and in some cases, can serve to normalize abnormal psychological activities. Neurotransmitters are commonly viewed as chemical that are located in specific regions of neurons, are released under specific stimulation, act on a specific set of receptors, and induce short-duration changes in membrane potential. A neuromodulator may induce a change in the binding of a neurotransmitter to its receptor, or it can act through secondary messengers to modulate neural responses to a neurotransmitter. A chemical that appears to play the role of a neurotransmitter in one area of the nervous system may play the role of a neuromodulator or neurohormone somewhere else in the body.