These peptides, including hypocretin/orexin (Hcrt), melanin-concentrating hormone (Mch), galanin (Gal), enkephalin (Enk), and dynorphin (Dyn), are heavily expressed in specific brain areas such as the hypothalamus, nucleus accumbens and amygdala that mediate drug consumption and other related behaviors that these peptides and areas control, including hyperactivity, anxiety, novelty seeking, exploration, impulsivity, and drug seeking, which are closely associated with the overconsumption of drugs. Here, HCRT is linked to Anxiety.