Neuropsychiatric illness in the later years of life: summary and synthesis.

Dealing with neuropsychiatric illness in the later years of life is an immersion in complexity, born of heterogeneity in etiology, pathogenesis, clinical presentation, and response to intervention. We offer here a conceptual summary and synthesis of the key theme of heterogeneity, as embodied in the 20 papers that constitute this issue of Neuropsychopharmacology Reviews (NPPR's). We conclude with future scientific directions and moral imperatives for research and practice, already underway in many instances, but gaining in speed and transformative potential (especially in generative Artificial Intelligence and Large Language Models). We seek to review and to encourage research that works toward practical wisdom-- what Aristotle termed "phronesis," for promotion of resilience and wellbeing in older adults both at the individual and population levels.