The barostat is a specialized device used to measure visceral perceptual thresholds and gastrointestinal (GI) wall distensibility by maintaining constant pressure within a polyethylene balloon positioned in the GI tract. Initially developed for gastric studies, its use has expanded to the small intestine, colon, and rectum. The barostat allows for precise assessment of perceptual thresholdsPerceptual threshold and adaptive relaxationAdaptive relaxation, particularly relevant in disorders of gut-brain interaction (DGBI)Disorders of gut-brain interaction such as functional dyspepsia (FD)Functional dyspepsia and irritable bowel syndrome (IBS).Irritable bowel syndrome Despite its diagnostic value, the barostat Barostattest is invasive, costly, and largely limited to research settings. In FD, it has revealed abnormalities in gastric accommodation and hypersensitivity, contributing to subtype classification and therapeutic evaluation. Pharmacological agents such as Rikkunshito and mosapride have demonstrated beneficial effects in barostat-based assessments. Further research integrating barostatBarostat findings with non-invasive imaging modalities—such as SPECT, scintigraphy, and ultrasonography—may enhance the diagnostic utility and clinical applicability of this method. The barostat remains an important tool in advancing our understanding of GI sensory-motor physiology.