Study of dynamic brain function in irritable bowel syndrome via Hidden Markov Modeling

Area of Science:

• Neuroscience
• Gastroenterology
• Computational Biology

Background:

• Irritable bowel syndrome (IBS) is a prevalent disorder characterized by unclear pathogenesis and altered brain-bowel interactions.
• Previous research has indicated functional brain abnormalities in IBS patients.

Purpose of the Study:

• To investigate dynamic changes in brain function in IBS patients using a Hidden Markov Model (HMM).
• To explore the temporal properties of brain activity states and their correlation with clinical symptoms in IBS.

Main Methods:

• Resting-state functional magnetic resonance imaging (rs-fMRI) data were collected from 35 IBS patients and 31 healthy controls (HCs).
• A Hidden Markov Model (HMM) was employed to identify distinct brain activity states and analyze their temporal dynamics (fractional occupancy, lifetime, and transition probabilities).
• Correlations between HMM state properties and clinical scale scores were examined.

Main Results:

• Six distinct HMM states were identified, with significant differences in fractional occupancy and lifetime observed in states 5 and 6 between IBS patients and HCs.
• Altered state transition probabilities were found in IBS patients, notably an increased likelihood of transitioning from state 2 to state 6.
• Dynamic reorganization of HMM states correlated with abnormal activity in the default mode network (DMN), sensorimotor network (SMN), and cingulo-opercular network (CON).

Conclusions:

• This study provides novel insights into the dynamic reorganization of brain activity patterns in IBS.
• The findings suggest potential links between altered brain dynamics and IBS-related emotional regulation and symptom experience.
• This research contributes to a deeper understanding of the neural mechanisms underlying IBS.