Beyond Comorbidity: Evolutionary Insights Into the Concomitance of Neurodivergence, Major Depressive Disorder, and Anxiety Disorders

Abstract

Mainstream psychiatry continues to interpret neurodivergence through a disease paradigm, assuming that all cases of autism and ADHD reflect disordered brain development. This framing has contributed to the view that elevated rates of co-occurring psychiatric diagnoses found in neurodivergent populations can be explained through shared mechanisms of neurobiological dysfunction. The neurodiversity movement has challenged this view, reframing neurodiversity as natural variation within human cognition, and emphasizing that much of the associated distress in neurodivergent individuals arises from systemic social barriers, rather than internal dysfunction. In contrast to the disease paradigm's individualizing focus, this relational perspective suggests psychopathology in neurodivergent individuals arises primarily from the poor fit between their cognitive profiles and modern environments. Evolutionary psychiatry may offer a scientific foundation for this reframing. Here, we synthesize evolutionary insights on autism, ADHD, and affective disorders to provide a novel explanation for elevated rates of major depression and anxiety disorders in neurodivergent populations, based upon the principles of evolutionary trade-offs and mismatch. This perspective offers a scientifically grounded and ethically progressive framework for understanding neurodivergence and its psychiatric comorbidities; one that emphasizes prevention and environmental accommodation, instead of pathologisation and deficit-correction.