This document discusses various cognitive enhancers and their mechanisms of action. It covers categories of enhancers like racetams, cholinergics, AMPAkines, and nootropic vitamins. Specific substances are explained, such as piracetam, aniracetam, citicoline, modafinil, and phenibut. Their impacts on neurotransmitters like acetylcholine, glutamate, dopamine, and GABA are described. Conditions they may help with include Alzheimer's, ADHD, depression, and neurodegenerative diseases. Their mechanisms involve increasing blood flow, neurotransmission, neuronal metabolism, and acting as antioxidants.