New Research Shows Changes in Brain Connectivity in Youth With Functional Abdominal Pain Disorders

Youth with functional abdominal pain disorders (FAPDs) have distinctive patterns of brain connectivity that could support the development of biomarkers and inform new treatment approaches, according to a study by researchers from Michigan State University and Cincinnati Children’s Hospital Medical Center. The study, which was partially funded by the National Center for Complementary and Integrative Health, was published in the journal Pain.

FAPDs, such as irritable bowel syndrome, are among the most common pain conditions affecting youth. They are thought to result from abnormal interactions between the brain and the gut, but the exact mechanisms of the interactions are poorly understood, diagnosis of the conditions is difficult, and treatment is challenging.

This study used functional magnetic resonance imaging (fMRI) to evaluate brain structure and function in 25 youths, ages 11 to 17, with FAPDs and 20 healthy control participants of similar ages. The focus of the study was on the amygdala because this brain region is associated with visceral pain (pain in or around the internal organs) and negative affect (emotional distress). A validated procedure called the water load symptom provocation task (WL-SPT), in which participants are asked to gradually drink water until they feel “completely full,” was used to induce abdominal pain or discomfort in the youth with FAPDs. Brain scans using fMRI were performed before and after drinking the water, and the participants rated the intensity and unpleasantness of their pain or discomfort after each scan. The healthy controls were scanned once, without doing the WL-SPT. 

The WL-SPT led to a 49 percent increase in pain unpleasantness and a 29 percent increase in pain intensity in the youth with FAPDs. fMRI scans performed before and after the WL-SPT showed changes in patterns of connectivity of the amygdala to other brain regions, including areas associated with nociceptive processing (relating to the perception or sensation of pain) or cognitive functioning, which were related to the changes in pain unpleasantness and intensity. The scans also showed differences in amygdala connectivity between the youth with FAPDs and the healthy controls.

These findings suggest that the brains of youth with FAPDs function differently than those of healthy youth, with distinctive patterns of amygdala connectivity. Understanding these patterns may help researchers develop biomarkers that could aid in identifying FAPDs and distinguishing them from other conditions. The study also demonstrated for the first time that the WL-SPT is a useful tool for neuroimaging of visceral pain in youth with FAPDs. The investigators noted that there are limited evidence-based treatments currently available for FAPDs and that the results of their study may inform the development and testing of better treatment approaches.