No evidence for unconscious attentional bias in people with clinically significant symptoms of functional gastrointestinal disorders: a study using the emerging electroencephalographic paradigm of fast periodic visual stimulation

Background: Disorders of gut-brain interaction (DGBIs) present a significant burden on global healthcare systems, yet their underlying mechanisms remain poorly understood. Emerging evidence suggests a role for unconscious psychological processes, particularly attention. This study seeks to detect unconscious attention patterns in people meeting DGBI diagnostic criteria using electroencephalographic (EEG) fast periodic visual stimulation (FPVS), a novel passive method offering high temporal resolution. Methods: Alongside 20 healthy controls, 22 female psychology students meeting Rome IV criteria for irritable bowel syndrome or functional dyspepsia completed an FPVS task involving symptom-related (oddball), negative (oddball), and neutral (base) nouns, as well as a control condition in which faces were oddballs among reshuffled pixels. Key Results: While we detected unconscious discrimination in the control condition, no significant difference in unconscious attention to symptom-related or negative nouns relative to neutral nouns was observed between groups. Conclusions and Inferences: In suggesting no basis for unconscious attentional bias in DGBIs, these findings echo research measuring unconscious attention using event-related potentials, but should be replicated using more highly valenced emotional words.