The intrinsic slow-wave rhythm of the stomach couples with ongoing cortical activity in humans, a phenomenon referred to as gastric–brain coupling. The functional significance of this coupling during cognitive challenges and its relationship with autonomic and psychological states remains unclear. The present preprint investigated how gastric–brain coupling changes during a mental task and subsequent recovery, and whether those dynamics relate to autonomic responses and psychological traits in healthy adults (HA) and people with irritable bowel syndrome (IBS), a disorder conceptualized as a disturbance of gut–brain interactions.
The study recorded brain and gastric activity simultaneously using electroencephalography (EEG) and electrogastrography (EGG) while participants performed a mental task followed by a recovery period. The goal was to quantify changes in gastric–brain coupling across task and recovery and to relate these changes to autonomic measures (indexed in the abstract as sympathetic arousal) and to psychological measures including anxiety, neuroticism, and interoceptive awareness. Specific methodological parameters such as sample size, task type and duration, and detailed autonomic measurement procedures were not reported in the abstract and should be consulted in the full manuscript or supplementary materials for exact details.
In healthy adults, the main pattern reported was a decrease in gastric–brain coupling during the cognitive task, followed by a gradual return toward baseline during the recovery period. This task-related modulation was most evident for cortical alpha rhythms, indicating that coupling involving alpha-band activity is particularly sensitive to cognitive demand. The findings suggest that gastric–brain coupling is a dynamic process that can be downregulated during externally focused cognitive activity and reinstated when cognitive load subsides.
Individuals with IBS displayed preserved gastric–brain coupling dynamics: coupling decreased during the mental task and returned during recovery similarly to healthy adults. Thus, the core temporal pattern of task-related modulation of gastric–brain coupling appears intact in IBS, according to the reported results.
A key distinction between groups concerned autonomic correlates. In healthy adults, greater reductions in gastric–brain coupling during the task were associated with stronger sympathetic arousal, supporting a link between the degree of task-related coupling change and physiological stress or arousal responses to cognitive demand. In contrast, this relationship between coupling reductions and sympathetic arousal was not observed in people with IBS. That absence suggests an altered functional relationship between gastric–brain coupling and autonomic regulation in IBS, despite preserved coupling dynamics.
Psychological correlates of coupling dynamics also diverged between groups. Among healthy adults, larger reductions in gastric–brain coupling were associated with higher anxiety and neuroticism, and with lower interoceptive awareness. By contrast, in the IBS group these relationships were reversed: individuals with higher anxiety and neuroticism and lower interoceptive awareness showed greater gastric–brain coupling dynamics. These opposite patterns indicate that the meaning or functional role of coupling changes differs between healthy individuals and those with IBS.
Taken together, the reported data position gastric–brain coupling as a dynamic physiological process that responds to cognitive demands and is linked to autonomic arousal and psychological traits in healthy adults. In IBS, coupling dynamics themselves are preserved, but their autonomic and psychological associations are altered. The authors interpret this as evidence for a dissociation in IBS between the physiological phenomenon of gastric–brain coupling and the typical functional correlates (autonomic reactivity and psychological correlates) observed in health.
This report is a preprint and has not been peer reviewed. The abstract and front matter summarize primary results but omit several methodological specifics (e.g., sample sizes, exact task details, statistical approaches, effect sizes). Those details are essential to evaluate the robustness, generalizability, and clinical relevance of the findings and are available in the full text and supplementary materials referenced by the preprint.
The study provides evidence that gastric–brain coupling is modulated by cognitive demand and, in healthy adults, tracks autonomic sympathetic responses and certain psychological traits. In IBS, temporal coupling dynamics during task and recovery are preserved, but their associations with sympathetic arousal, anxiety, neuroticism, and interoceptive awareness are altered, implying a dissociation between gastric–brain coupling and its usual functional correlates in this disorder. Further scrutiny of the full methods and peer review are warranted to confirm and extend these observations.