Neuropsychiatric symptoms in Alzheimer’s disease: Bridging mechanisms, management, and emerging innovations☆

Abstract Neuropsychiatric symptoms (NPS) are among the most distressing and functionally disruptive features of Alzheimer’s disease (AD), affecting the vast majority of individuals across the disease continuum. These symptoms, ranging from apathy and depression to agitation and psychosis, not only worsen quality of life but also predict faster decline, earlier institutionalization, and heightened caregiver burden. Yet, despite their clinical significance, NPS remain under-recognized and undertreated. This review synthesizes current understanding of the biological underpinnings of NPS in AD, highlighting network-level