Complex of global functional network as the core of consciousness.

The posterior brain regions, especially the 'hot zone' for phenomenal consciousness, are central to integrated information theory (IIT). This study used fMRI data from the Human Connectome Project and sleep datasets to estimate the 'main complex'—a set of brain elements where information loss is greatest when partitioned hierarchically. The main complex during wakefulness included executive control, salience, and dorsal/ventral attention networks. These networks persisted during sleep, but the amount of information within them and the default mode network decreased during the hypnagogic stage. The findings suggest that a global interconnected structure of major functional networks may form the core of consciousness.

Study at a glance

Abstract

Finding the neural basis of consciousness is challenging, and the distribution location of the core of consciousness remains inconclusive. Integrated information theory (IIT) argues that the posterior part of the brain is the hot zone of consciousness, especially phenological consciousness. The IIT has proposed a "main complex", a set of elements determined such that the information loss in a hierarchical partition approach is the largest among those of any other supersets and subsets, as the core of consciousness in a dynamic system. This approach may be applicable not only to phenomenal but also to access-consciousness. This study estimated the main complex of brain dynamics using functional magnetic resonance imaging in Human Connectome Project (HCP) and sleep datasets. The complex analyses revealed the common networks across various tasks and rest-state in HCP, composed of executive control, salience, and dorsal/ventral attention networks. The set of networks of the main complex was maintained during sleep. However, compared with the wakefulness stage, the amount of information of these networks and the default mode network, was reduced for the hypnagogic stage. The global interconnected structure composed of major functional networks can comprise the core of consciousness.