Neurologic & Psychiatric Peptides Revolution Health & Wellness Have you heard of the peptide DIHEXA? This is an amazing peptide for cognitive function, short and long term memory, and improves focus! DIHEXA, a synthetic peptide designed to Dihexa (also known as PNB 0408) is an experimental small molecule derived from angiotensin IV. It was engineered to cross the bloodbrain barrier and has shown synaptogenic effects in preclinical models. The often quoted Activation of neurogenesis improves amyloid pathology and cognitive function through AMP kinase signaling in Alzheimer's disease model mice ScienceDirect