The brain’s capacity to reorganize its structure and function by forming new neural connections, strengthening existing synapses, or pruning unused ones. Neuroplasticity underlies learning, memory formation, and recovery from brain injury. It was once believed to be limited to early development; it is now established that neuroplasticity continues throughout life, though at reduced rates.

Several peptide compounds are studied for neuroplasticity-enhancing effects: Semax modulates BDNF expression and has been investigated for stroke recovery; Selank affects GABAergic and serotonergic systems involved in synaptic plasticity; Dihexa was designed as an angiotensin IV analog targeting the hepatocyte growth factor (HGF) system involved in dendritic spine formation. The clinical significance of these preclinical findings for human cognitive function remains largely unestablished—enhancing neuroplasticity in cell cultures or rodent models does not automatically translate to cognitive improvement in humans.