Background:
Resting-state networks associated with a variety of functions, such as sensorimotor, auditory, visual, cognitive, and emotional information processing were extracted. In contrast to consistent extraction of resting-state networks across the studies, their functional relationships remain unclear.

Methods:
We applied the group independent component analysis on the functional magnetic resonance imaging (fMRI) data taken from 23 healthy adults [12 females and 11 males; age: 18.3-23.9 years (mean = 20.9); Japanese; right-handed]. They were kept at rest during the session and were instructed to lay with their eyes closed, think of nothing in particular, and stay awake. The extracted networks were further subjected to cluster and correlational analyses by which we explored their functional relationships.

Results:
Twenty networks were extracted and were clustered into six groups. The networks within the groups had positive correlations, whereas networks across the groups tended to have negative or no correlations. The default mode network (DMN) had stronger correlations with visual networks than with any other networks. The salience network was negatively correlated with the DMN, whereas the frontoparietal networks did not show any negative correlations with the DMN.

Conclusions:
These results suggest that, although participants did not perform any tasks, a variety of information processes progressed during the resting-state fMRI session. Judging from a wide distribution of positive correlations between the DMN and the visual, sensorimotor, and attention networks, resting-state information processing was related to internal visual information processing, such as scene construction, episodic memory recall, and future thinking. Sensory and emotional awareness and self-control were also implicated. These results were consistent with what the participants reported in the post-scan interview.