Joseph Knoll and his team are credited with having developed selegiline. Although selegelines development as a potential treatment for Parkinsons, Alzheimers, and major depressive disorder was headed by other teams, Knoll remained at the forefront of research into the potential longevity enhancing effects of selegiline up until his death in 2018. Knoll published How Selegiline ((-)-Deprenyl) Slows Brain Aging (2018) wherein he claims that:The mechanism of selegilines longevity-promoting effect has been researched by several groups, including Joseph Knoll and his associates at Semmelweis University, Budapest. The drug has been determined to be a catecholaminergic activity enhancer when present in minuscule concentrations far below those at which monoamine oxidase inhibitory activity can be observed, thereby potentiating the release of catecholamine neurotransmitters in response to stimuli. Knoll maintains that micro-doses of selegiline act as a synthetic analogue to a known or unknown trace amine in order to preserve the brain catecholaminergic system, which he perceives as integral to the organism's ability to function in an adaptive, goal-directed and motivated manner during advancing physical age: