Summary: Using the Hierarchical Taxonomy of Psychopathology (HiToP) framework, researchers analyzed self-reported motor symptoms alongside psychological dimensions in nearly 3,500 people without prior formal psychiatric diagnoses. The study compared motor measures—such as dyskinesia, coordination difficulties, developmental motor delays, and levels of physical activity—with psychological domains including distress, fear, dissociation, mania, psychosis-like experiences, and substance use.
Results show that motor abnormalities serve both as broad indicators of general psychopathology risk and as specific predictors for particular symptom clusters. Models separating symptoms into multiple factors (roughly five to eight) fit the data substantially better than single-factor approaches, supporting the case for integrating motor signs into transdiagnostic clinical frameworks.
Key Facts
- Dual diagnostic value: Motor symptoms can indicate overall vulnerability to mental health problems while also pointing to particular symptom domains, helping reconcile contradictory findings in prior psychiatric research.
- HiToP perspective: The study used the Hierarchical Taxonomy of Psychopathology to map motor signs across a layered spectrum—from broad dimensions like internalizing and psychosis down to dissociation, fear, and distress—rather than treating disorders as strictly separate categories.
- Best-fitting models: Multi-factor solutions (approximately five to eight factors) provided the best fit, showing clinical benefit in distinguishing specific symptom clusters instead of relying on a single general factor.
- Specific motor-psychopathology links: Dyskinesia, coordination problems, and overall motor difficulties showed positive associations with distress, fear, and dissociation. By contrast, physical activity was positively associated with mania and substance use and inversely associated with detachment, fear, and distress.
- Noninvasive early indicators: Because motor behavior is easy to measure, developmentally meaningful, and tied to identifiable neural circuits, motor signs offer an accessible avenue for early risk detection and monitoring.
Source: APS
Motor signs—such as coordination problems, slowed movements, or sudden uncontrolled motions—have been observed in psychiatric descriptions since the 19th century, yet how they map onto contemporary diagnostic concepts has remained unclear.
“When something has been observed since the earliest concepts of disorders, it suggests a meaningful signal,” said Jessica Fattal, a graduate student in Vijay Mittal’s lab at Northwestern University.
Motor abnormalities are well documented in psychosis but also occur across depression, bipolar disorder, attention-deficit/hyperactivity disorder, schizophrenia, and autism spectrum disorder. Motor function is straightforward to assess, grounded in known neural circuitry, and relevant across development, daily functioning, and social behavior.
Clarifying how motor abnormalities relate to mental health can inform mechanisms, course, and possible interventions. A central question is whether motor signs reflect a general vulnerability to psychopathology or whether they indicate risk for specific syndromes.
“Are motor symptoms broadly related to any psychopathology, or do they point more strongly to particular conditions—like psychosis—while being less relevant to others, such as anxiety?” Fattal asked.
In a 2026 paper in Clinical Psychological Science, Fattal and colleagues tested these possibilities using HiToP, a hierarchical dimensional model that treats mental-health phenomena as overlapping spectra rather than discrete illnesses. HiToP organizes symptoms from broad domains (for example, internalizing and psychosis) down to subdimensions (such as dissociation, fear, and distress) and individual symptom clusters.
The sample consisted of 3,460 participants from the Multi-Site Assessment of Psychosis-Risk study who reported no prior formal mental health diagnoses. Participants completed questionnaires assessing psychotic-like experiences, depression, anxiety, mania, dissociation, and substance use, along with self-reported motor features including early developmental delays, involuntary movements, coordination difficulties, and physical activity level.
Analyses compared alternative factor structures to determine whether motor symptoms loaded on a single general factor or related specifically to distinct symptom dimensions. If motor abnormalities were simply broad indicators of general psychopathology, a one-factor model would outperform more differentiated structures. If, instead, motor signs predict specific clusters, multi-factor solutions would fit better.
“Models that separated symptoms into clusters performed better overall,” Fattal reported. “Across analyses, solutions with around five to eight factors provided the best balance of fit and interpretability, indicating useful differentiation among symptom domains.”
Across models, overall motor problems, dyskinesia, and coordination difficulties showed positive associations—of varying strength—with multiple symptom domains, including distress, dissociation, and fear. Physical activity displayed a distinct pattern: higher activity was linked to greater mania and substance use but to lower detachment, fear, and distress.
“Most psychological symptom domains were tied to greater motor abnormalities, but they differed in how strongly and in what direction they related to specific motor features,” Fattal explained. “Physical activity is a clear example of a motor feature that relates differently across dimensions.”
The study concludes that motor abnormalities can function both as general endophenotypic markers of psychopathology risk and as indicators that help predict more specific conditions, such as psychosis or depressive syndromes. These findings support incorporating motor assessment into transdiagnostic evaluation systems like HiToP.
“The main takeaway is that motor signs deserve greater attention,” Fattal said. “We need more research to determine how to integrate motor measures into clinical practice to better identify and help people at risk of serious mental illness.”
Key Questions Answered:
A: HiToP is a dimensional clinical framework that organizes mental-health phenomena on overlapping spectra rather than as isolated categories. It places symptoms hierarchically—from broad domains like internalizing or psychosis to narrower sub-factors and individual symptoms—enabling transdiagnostic analysis and comparison.
A: Motor issues such as slowing, poor coordination, or involuntary movements appear across many distinct conditions (including schizophrenia, mood disorders, autism, and ADHD). Because traditional diagnostic systems treat disorders as discrete categories, it was unclear whether motor signs indicate general brain vulnerability or are specific to certain syndromes.
A: Unlike dyskinesia and coordination problems—which tended to increase alongside psychological distress—physical activity showed directional variation: it correlated positively with mania and substance use and negatively with detachment, fear, and distress.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The journal paper was reviewed in full for accuracy.
- Additional contextual information was provided by staff editors.
About this psychopharmacology and eating disorder research news
Author: Hannah Brown
Source: APS
Contact: Hannah Brown – APS
Image: Image credited to Neuroscience News
Original Research: Open access. “Motor Abnormalities and the Hierarchical Taxonomy of Psychopathology: Incorporating a Psychomotor Perspective Into a Hierarchical Dimensional Symptom Framework” by Jessica Fattal et al., Clinical Psychological Science. DOI: 10.1177/21677026261450607
Abstract
Motor Abnormalities and the Hierarchical Taxonomy of Psychopathology: Incorporating a Psychomotor Perspective Into a Hierarchical Dimensional Symptom Framework
Motor symptoms are an increasingly important target for research into mechanisms, prognosis, and treatment in mental health. Although motor abnormalities occur across many conditions, transdiagnostic investigation has been limited. It remains unclear whether motor signs mainly index a broad vulnerability or predict particular symptom patterns.
Using a hierarchical dimensional symptom structure, the study examined relationships between psychological symptoms and self-reported motor features in 3,460 participants from the Multi-Site Assessment of Psychosis-Risk study.
Overall motor problems (βs = 0.07–0.25), dyskinesia (βs = 0.07–0.31), and coordination difficulties (βs = 0.05–0.23) were positively associated—at varying strengths—with multiple symptom domains. Physical activity related positively to mania and substance use (βs = 0.08–0.09) and negatively to detachment, fear, and distress (βs = 0.05–0.27).
These results indicate that motor domains may serve both as a general endophenotypic marker and as more specific predictors of serious mental illness, with implications for future research and clinical practice.