Neural plasticity-the ability to change and adapt in response to stimuli-is an essential aspect of healthy brain function and, in principle, can be harnessed to promote recovery from a wide variety of brain disorders. Many neuropsychiatric diseases including mood, anxiety, and substance use disorders arise from an inability to weaken and/or strengthen pathologic and beneficial circuits, respectively, ultimately leading to maladaptive behavioral responses. Thus, compounds capable of facilitating the structural and functional reorganization of neural circuits to produce positive behavioral effects have broad therapeutic potential. Several known drugs and experimental therapeutics have been shown to promote plasticity, but most rely on indirect mechanisms and are slow-acting. Here, I describe psychoplastogens-a relatively new class of fast-acting therapeutics, capable ofrapidly promoting structural and functional neural plasticity. Psychoplastogenic compounds include psychedelics, ketamine, and several other recently discovered fast-acting antidepressants. Their use in psychiatry represents a paradigm shift in our approach to treating brain disorders as we focus less on rectifying "chemical imbalances" and place more emphasis on achieving selective modulation of neural circuits.

Declaration of conflicting interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

• R01 GM128997/GM/NIGMS NIH HHS/United States
• U54 HD079125/HD/NICHD NIH HHS/United States