Neuropeptides are small protein-like molecules used by neurons to communicate with each other. They play a crucial role in modulating various brain functions, including pain perception, stress response, and emotional regulation. Neuropeptides are released from nerve cells and can influence the activity of other neurons, affecting behaviors and physiological processes. These molecules are distinct from traditional neurotransmitters, as they often have longer-lasting effects and can act on a wider range of receptors. Examples of neuropeptides include endorphins, which help alleviate pain, and oxytocin, known for its role in social bonding and reproduction.