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Neurodiversity* celebrates the complexity of the human psyche and emphasizes the natural differences that exist within populations. In recent years, the growing popularity of neurodiversity has led to the widespread recognition and diagnosis of neurodevelopmental disorders such as autism, attention deficit hyperactivity disorder (ADHD), dyslexia, dyscalculia, and movement disorders.
Neurodiversity: At its core, it is the idea of recognizing that those so-called "disorders" are in fact normal variations in human cognition, emotion, learning, and neurological function. The concept emphasizes that just as biodiversity is essential to the health and sustainability of ecosystems, neurodiversity is a key component of the health and creativity of human populations. This perspective promotes a more inclusive perspective in which each person's brain and psychological differences are seen as an asset, not a flaw.
Our understanding of these diseases is based on research in a variety of research areas, including developmental and social sciences, cognitive neuroscience, psychiatry, education, and clinical, health, and biomedical sciences, with a particular focus on neurobiology and genetics. Together, these fields work to unravel the mechanisms and hallmarks of neurodevelopmental diseases, from genetic to societal levels.
However, given the great heterogeneity within neurodevelopmental disorders and between their research fields, there is a huge gap in truly interdisciplinary neurodiversity research. This inadequacy highlights many overlooked opportunities for collaborative work. This article explores five key challenges facing the field and identifies possible opportunities for future developments.
▷Olujolagbe LayinkaLuca D HargitaiPunit ShahLucy H WaldrenFlorence YN Leung (2024) Point of View: Five interdisciplinary tensions and opportunities in neurodiversity research eLife 13:e98461.
https://doi.org/10.7554/eLife.98461
Dimensional traits and categorization barriers
传统上，研究者们常将神经发育疾病归类为离散的、范畴化的“障碍”，这一观点与《精神疾病诊断和统计手册》（Diagnostic and Statistical Manual of Mental Disorders）[American Psychiatric Association, 2013]的立场一致。 这种分类方式促进了对神经发育疾病的医学化处理，并支持了这些疾病源自个体内部生物缺陷的看法。
Recently, however, researchers have begun to believe that neurodevelopmental disorders, especially autism, are more appropriately considered as a dimensional spectrum that includes a set of measurable traits that are persistently distributed in the general population [Happé and Frith, 2020]. This "trait approach" differs from traditional categorization disorders in that it essentially fits in with the inclusive spirit of the neurodiversity movement, which considers neurologically different traits as part of the natural variation in a population.
There is an argument that the dimensional perspective of neurodevelopmental disorders contributes to the misconception that anyone can be "a little autistic" or "a little impaired in motor coordination". For example, there has been controversy about whether there is a clear difference in the quality and quantity of autism traits and autism spectrum disorder diagnoses [Happé and Frith, 2020]. However, current evidence clearly shows that neurodevelopmental disorders with high traits that do not meet clinical diagnostic criteria are prevalent and that these conditions predict poorer health outcomes [Thapar et al., 2017]. Trait approaches are also better able to explain the complex diversity of human characteristics within the same diagnosis [Lyall, 2023]. In addition, the trait approach is more closely related to the biological processes underlying neurodevelopmental diseases. For example, specific genes are associated with autism traits rather than diagnosis [Lee et al., 2022].
Therefore, it is time for research to use a trait approach to explore the shared and unique mechanisms behind neurodevelopmental diseases. This includes cross-diagnostic studies that explore different levels of trait domains, such as sensorimotor, regulatory, cognitive, and social processes, within a framework of research domain standards [Cuthbert and Insel, 2013]. When successfully applied, this framework will enable a deeper understanding of individual differences, both within and outside the boundaries of traditional diagnostic "barriers".
Disagreement: Language differences between disciplines
As we deepen our understanding of the neurodiversity paradigm, the use of terminology has changed significantly. Traditional research has tended to use deficit-based language, while neurodiversity communities have advocated for more inclusive language [Monk et al., 2022]. For example, the use of inclusive language has become more prevalent in behavioral and cognitive research, while the journal Neurodiversity (co-edited by PS) explicitly discourages the use of defect-based language. In contrast, the biomedical field is more inclined to stick to standard medical terminology due to its essential nature. This linguistic difference between disciplines has led to tensions between researchers in different fields, as well as between the neurodiversity community and some researchers. Therefore, building trust is essential for successful interdisciplinary neurodiversity research.
In addition to differences in language use, different disciplines also differ in defining concepts related to neurodiversity research. A variety of different but overlapping terms are used in the literature to describe the same concept, which complicates the clarification of the specific mechanisms and processes observed. For example, the terms "sensitivity", "reactivity", and "responsivity" are used interchangeably to describe differences in sensory processing in various neurodevelopmental disorders [He et al. 2023]. This terminological inconsistency reflects the increasingly common "jingle jangle fallacy" in scientific research, which mistakenly treats two different things as the same because they have the same name, or because they have different names, and this confusion constitutes a major obstacle to developing an interdisciplinary understanding of neurodevelopmental processes. To coordinate research across disciplines, researchers first need to agree on at least a definition of terminology in the neurodevelopmental processes they wish to study [Shah et al., 2022].
Look for common goals
Differences in terminology exacerbate a fundamental challenge in neurodiversity research: inconsistencies in research methods across disciplines. In the field of genetics and neuroscience, research typically focuses on the medicalization of neurodevelopmental diseases and the search for potential "targets" for individualized interventions at the neurobiological level. Hundreds of genes have been implicated in various neurodevelopmental disorders [Genovese and Butler, 2023]. However, although these disciplines contribute the "neurological" component to neurodiversity, their research goals are increasingly at odds with those of the groups they wish to help [Russell and Wilkinson, 2023]. For example, research has shown that the autism community is more likely to focus on tangible areas that directly affect and improve their daily lives, rather than just exploring the underlying biological mechanisms that may underpin certain "deficiencies" [Pellicano et al., 2014].
Thankfully, opportunities for interdisciplinary dialogue between scholars and the neurodiversity community are growing, particularly in the United Kingdom and the United States (such as the Autism Research Festival, the International Society for Autism Research Annual Meeting, and the It Takes All Kinds Of Minds conference), which provide a respectful and stimulating learning space for both parties to help align research goals. In addition, by enhancing the social impact of research results, public participation activities are expected to repair the current fractured relationship between researchers and the community.
Resource allocation
The uneven distribution of resources and funds across disciplines hinders the achievement of common goals. For example, between 2014 and 2017, 47% of mental health research funding in the United Kingdom went to deficit-focused, biomedical-based areas, while only 9% went to improving mental health services [MQ Transforming Mental Health, 2021].
A further comparison of funding allocations for different neurodevelopmental disorders found that funding for autism research in the United Kingdom was roughly equal to that of all other neurodevelopmental disorders combined. This apparent preference for funding agencies creates a vicious circle that makes lesser-known diseases more likely to be overlooked, such as dyscalculia and motor coordination disorders.
▷ Comparison of the number of academic outputs for eight neurodevelopmental disorders from 2003 to 2023 with the year. Data from Google Scholar
Having said that, neurodiversity research can greatly benefit from collaboration in different fields of research. For example, data from brain imaging and eye tracking can complement the interpretation of behavioral performance on cognitive tasks, which in turn can reveal meaningful information about the (compensatory) processing strategies employed in different neurodevelopmental disorders, such as autism and movement disorders [Livingston and Happé, 2017]. This not only alleviates the financial pressures and financial constraints associated with the discipline, but also maximizes our understanding of the complexities and connections between neurodevelopmental disorders.
Advocate for the right balance
In addition to research funding, we also need to balance the research lens of neurodiversity. In addition, inclusive research practices, such as meaningful collaborative production, patient and public engagement opportunities, neurodiversity advisory committees, etc., can also help achieve research excellence and ensure that research is aligned with the overall priorities of the neurodiversity community [Hobson et al., 2023]. But the process is not simple, as different voices exacerbate existing tensions, and the competition between different perspectives needs to be balanced.
The recent controversy surrounding the Spectrum 10K genome-wide association study around autism has been suspended due to concerns from some in the neurodiversity community [Natri, 2021]. Despite the outcry, follow-up studies have shown that parents of children with nonverbal autism actually support genetic research and believe that their children are often neglected by the autism community and do not receive enough attention [Asbury et al., 2024]. This situation also resonated with those who were considered to be less functioning [Singer, 2022] and was reflected in the demographics of study participants [Russell et al., 2019]. These insights prompt us to rethink the reliability and representativeness of generally accepted views in neurodiverse populations to ensure they truly reflect the community as a whole.
Therefore, researchers should consider whether the "empirical experts" who inform their research are truly representative of the diverse individuals they want to know. Investigator input has been optimized through initiatives that reduce reliance on patient and public engagement groups and systematically capture a broader perspective. For example, the Regulating Emotions – Strengthening Adolescent Resilience (RE-STAR) program recently established a new participatory model that provides guidance for the effective integration of young people with ADHD and/or autism into translational research [Sonuga-Barke et al., 2024].
Coupled with open science practices, these approaches are invaluable for translating valid and reliable research results into something that has a profound impact on the community [Hobson et al., 2023]. For example, pre-registration for a study plan requires the investigator to carefully consider the study question, design, and target population before the study begins, which can help to better contextualize and interpret the findings. At the same time, making data and analysis codes open allows other researchers to independently verify the results of the study, thereby raising the overall standard of neurodiversity research.
Boundary Definition of Neurodiversity
While this article discusses the major tensions and opportunities in neurodiversity research, this article stops at the research and practical problems of "common" neurodevelopmental disorders, which is a limitation. We need to recognize that neurodiversity is a broad and expanding term that is likely to continue to expand with the inclusion of other disorders such as schizophrenia, bipolar disorder, and epilepsy [Morris-Rosendahl and Crocq, 2020]. In fact, conditions such as developmental facial recognition disorder (difficulty recognizing faces), congenital aphonia (phonic denia), and heart blindness (difficulty forming mental images) may also fall into this category, given that they are associated with cognitive and perceptual differences in neurodevelopment.
Where are the boundaries of neurodiversity? This is an ontological question to be answered in neurodiversity research. Understanding the beginning and end points of neurodiversity may actually influence research in this area, making it more empirically operational. But if neurodiversity is seen as a natural part of human variation, should we set a beginning and an end point? If not, do we ultimately need to abandon the concept of "condition"? While we cannot be sure of the answers to these questions, we are convinced that these fundamental questions can only be addressed through interdisciplinary collaboration and joint efforts with the neurodiversity community to conduct high-quality research.
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