Abstract
Autism spectrum disorder (ASD) is traditionally conceptualized as a pathological condition characterized by impairments. However, a growing body of scientific evidence supports understanding autism as a naturally occurring neurodevelopmental variant shaped by complex genetic and environmental factors and maintained through evolutionary mechanisms. This article is a review that synthesizes current knowledge from genetics, neuroscience, and evolutionary biology to argue that autism represents a natural neurotype rather than a disorder. It also addresses common misconceptions rooted in deficit-focused medical models and highlights the neurodiversity paradigm’s implications for research, practice, and social inclusion.
Introduction
Autism spectrum disorder (ASD) has long been viewed within a medical framework emphasizing deficits and disorder. Emerging interdisciplinary research, however, increasingly supports a neurodiversity perspective that frames autism as a fundamental variation in human neurobiology and phenotype. This article reviews the scientific evidence on autism’s genetic, neurobiological, and evolutionary bases. It further critiques prevailing misconceptions and outlines the neurodiversity paradigm’s contribution to reframing autism as a natural and valuable aspect of human diversity.
Neuroscience and Genetics: Autism as a Developmental Variant
Genetic studies highlight autism’s complex, heterogeneous etiology involving numerous genes affecting neurodevelopmental processes such as chromatin remodeling, synaptic formation, and neuronal connectivity. Polygenic inheritance, combined with environmental influences mediated through epigenetic mechanisms, shapes the wide neurodevelopmental variability observed in autism. Neuroimaging supports this by showing diverse brain structure and connectivity differences rather than a singular pathological phenotype. Notably, many autism-associated variants relate to traits advantageous in particular contexts, lending credence to autism as part of normal genetic diversity (Sandin et al., 2025; De Rubeis et al., 2019; Amador et al., 2024).
Evolutionary Perspectives: Persistence of Autism Traits
Evolutionary biology explains the maintenance of autism-linked genetic variants due to their multifaceted roles, including potential cognitive or behavioral benefits. Rather than being solely deleterious, these variants contribute to adaptive neurocognitive diversity. Autism can be conceptualized as an alternative neurodevelopmental trajectory shaped by evolutionary pressures, reinforcing its status as a natural variation in human populations rather than an anomaly (Nadeau, 2011).
Addressing Misconceptions and Medical Model Limitations
The traditional medical model often emphasizes deficits and individual pathology, leading to stigma and exclusion. The social model of disability reframes disability as the consequence of societal failure to accommodate neurological variation. This view recognizes that disabling experiences arise from environmental and social barriers rather than intrinsic impairment. Additionally, neurodiversity includes autistic individuals across the spectrum, affirming their worth beyond functionality and emphasizing acceptance and accommodation rather than normalization (Fletcher-Watson et al., 2021).
The Neurodiversity Paradigm: Scientific and Social Implications
The neurodiversity framework encourages research and practice that prioritize autistic individuals’ perspectives and dignity, moving beyond deficit remediation to affirmation and support. It advocates for participatory research, inclusive policies, and societal adjustments to embrace neurological difference as a dimension of human diversity. This paradigm shift aligns closely with contemporary genetic and neuroscientific findings, promising more ethical and effective approaches (Jones et al., 2025; Sandin et al., 2025).
Conclusion
Rigorous scientific evidence supports autism as a naturally occurring, genetically-influenced neurodevelopmental variant maintained through evolutionary mechanisms. Recognizing autism within the neurodiversity paradigm dismantles limiting deficit models, fostering respect for neurological diversity and promoting supportive environments. This perspective advances more inclusive research, policy, and social understanding.
References
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Sandin, S., Lichtenstein, P., Kuja-Halkola, R., Hultman, C.M., Larsson, H., & Reichenberg, A. (2025). Unraveling the genetic and environmental risk factors of autism spectrum disorder. Nature Neuroscience, 28(2), 123-135. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12050264/