New Swedish study sheds light on obsessive–compulsive symptoms in children with PANS
GNC’s latest published research on PANS and OCD, with Helena Holmäng as first author alongside a multidisciplinary research team.
Children with Paediatric Acute-onset Neuropsychiatric Syndrome (PANS) experience a sudden and dramatic onset of obsessive–compulsive disorder (OCD) alongside a range of other neuropsychiatric difficulties. Although OCD is a central feature of PANS, knowledge remains limited regarding how symptom severity relates to cognitive processes such as attention, processing speed, and decision-making.
A research group at the Gillberg Neuropsychiatry Centre at the University of Gothenburg has now conducted a new study that contributes to a deeper understanding of these relationships. The study, recently published in the Journal of Clinical and Experimental Neuropsychology, examines the relationship between speed and accuracy in a reaction-time task in children and adolescents with PANS, and how these measures are associated with variations in obsessive–compulsive symptoms.
PANS and obsessive–compulsive symptoms: A clinical context
PANS was introduced in 2012 as a broader clinical framework for children with an acute onset of severe neuropsychiatric symptoms. The concept builds on earlier descriptions of PANDAS (Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections), first described in the late 1990s. Over time, it became clear that streptococcal infection alone was too narrow a criterion, as both infectious and non-infectious factors can trigger similar symptom profiles.
PANS is characterised by an abrupt and dramatic onset of OCD and/or restrictive eating, in combination with other neuropsychiatric symptoms, such as anxiety, emotional instability, oppositional behaviours, behavioural (developmental) regression, deterioration in school performance, and motor or sensory abnormalities. PANS often follows a fluctuating course, which poses particular challenges for clinical assessment and follow-up.
Previous research has shown that obsessive–compulsive symptoms are often characterised by a strong drive for correctness, symmetry, and safety. In individuals with OCD, this has sometimes been associated with a tendency to prioritise error-free responses over speed. However, findings have been inconsistent, especially in studies involving children. Against this background, the present study aimed to move beyond simple reaction-time measures and instead examine how response style, accuracy, and precision covary with symptom severity.
Study design and methods
The study included 12 children and adolescents with PANS, aged 6.5 to 16.5 years (median age 11 years). Each participant completed a tablet-based reaction-time task on two to four occasions during the study period, resulting in a total of 39 test sessions. This repeated-measures design made it possible to track changes both within individuals over time and between participants.
In the task, children were instructed to press one of four buttons on a touchscreen as soon as it lit up. Analyses focused on the first five minutes of each test session. In addition to reaction time, researchers recorded how often the correct button was pressed and how the finger press was positioned relative to the centre of the button.
At each session, the severity of obsessive–compulsive symptoms was assessed using a clinician-administered scale, with scores ranging from 0 (no symptoms) to 20 (severe symptoms). The average score was around 10, corresponding to mild symptoms, but within-individual variability was substantial. This provided favourable conditions for analysing how changes in symptom severity were associated with changes in test results.
Increased accuracy rather than general slowing
One of the more unexpected findings was that researchers did not observe a direct association between OCD symptom severity and average reaction time. On average, children responded in just under one second, and higher symptom levels did not per se predict slower responses.
Instead, a clear pattern emerged in how children performed the task. When obsessive–compulsive symptoms were more pronounced, responses became both more accurate and more precise. For every five-point increase in symptom severity, the number of correct responses increased by approximately one. At the same time, finger presses were placed on average about 0.8 millimetres closer to the centre of the button, indicating greater precision in movement execution.
This response tendency, however, came at a cost. When children combined high accuracy with precise, centrally placed finger presses, reaction times tended to be longer. Interestingly, slower responses were also observed in the opposite case, when both accuracy and precision were low. The fastest responses were seen when responses were correct, but without simultaneously exhibiting high precision in finger placement.
Clinical implications and future perspectives
The findings suggest that performance in children with PANS is less about general cognitive speed and more about heightened self-monitoring and careful responding. Children with more pronounced obsessive–compulsive symptoms appear to do things “right” and “neatly,” even when this means working more slowly.
For clinicians, this represents an important nuance. Slower performance does not necessarily reflect impaired ability but may instead indicate adaptive yet time-consuming strategies. Assessments that focus solely on reaction time therefore risk overlooking key aspects of how children approach tasks. Measures of accuracy and movement precision may provide a more comprehensive picture.
The study also highlights the potential value of digital assessment tools, which can capture subtle behavioural patterns that are difficult to observe in routine clinical practice. In the longer term, interventions that help children tolerate imperfection and reduce excessive self-monitoring may support more flexible and efficient functioning—both in testing situations and in everyday activities such as schoolwork.
Despite its small and exploratory design, the study represents an important step toward a better understanding of how obsessive–compulsive symptoms in PANS may influence how children perform tasks, and how behaviours characterised by high accuracy and precision – doing things “just right” – may be linked to slower responses.
Text by Anna Spyrou, Communications Officer
Link to article:
Holmäng H, Fagerudd R, Hajjari P, Huldt Oldmark M, Jakobsson K, Serrano Toro A, Vinsa I, Fernell E, Hadjikhani N, Gillberg C, Åsberg Johnels J, Johnson M, Thorsson M. Trade-off between speed and accuracy: associations between obsessive-compulsive symptoms and meticulousness in PANS. J Clin Exp Neuropsychol. 2026 Jan 20:1-12. doi: 10.1080/13803395.2026.2617355. Epub ahead of print. PMID: 41560412.
