Boredom is a complex psychological state, often seen as a double-edged sword. It can promote creativity, but is also linked to negative effects, such as irritability, fatigue, and even self-directed aggression. To better understand the neural underpinnings of boredom, this study applies Integrated Information Theory (IIT) to investigate how brain–body interactions reflect this state. Using electroencephalography (EEG) and autonomic measures (electrodermal activity and electrocardiography), we examined participants engaged in arithmetic tasks of varying difficulty levels. Our findings reveal that system integration, quantified by integrated information ( \(\Phi\) ), increased during both easy and difficult tasks compared to the moderate condition. In contrast, the dynamical properties of the main complex—a core subset within IIT—showed an opposite trend, indicating improved body–brain coupling specifically during moderate tasks. Moreover, analyses using Earth Mover’s Distance revealed significant shifts in the main complex’s distribution during moderate tasks, whilst there were minimal changes under the easy condition. Interestingly, subjective reports indicated that irritation and tiredness were linked to transitions in the main complex, whilst boredom showed no correlation with \(\Phi\) . These results suggest that boredom may emerge from a decoupling between brain and body systems, despite heightened system integration. Conversely, stronger body–brain coupling—characteristic of the moderate task condition—may buffer against subjective stress. This research highlights the potential of IIT for quantifying internal states like boredom and emphasises the need for further studies with larger, more diverse samples to validate and generalise these findings.
