Resting-state networks in the infant brain

Abstract

In the absence of any overt task performance, it has been shown that spontaneous, intrinsic brain activity is expressed as systemwide, resting-state networks in the adult brain. However, the route to adult patterns of resting-state activity through neuronal development in the human brain is currently unknown. Therefore, we used functional MRI to map patterns of resting-state activity in infants during sleep. We found five unique resting-states networks in the infant brain that encompassed the primary visual cortex, bilateral sensorimotor areas, bilateral auditory cortex, a network including the precuneus area, lateral parietal cortex, and the cerebellum as well as an anterior network that incorporated the medial and dorsolateral prefrontal cortex. These results suggest that resting-state networks driven by spontaneous signal fluctuations are present already in the infant brain. The potential link between the emergence of behavior and patterns of resting-state activity in the infant brain is discussed.

Fig. 1.

Resting-state networks in a single infant. Five resting-state networks are shown that were consistently observed in all infants. Each row represents one resting-state network shown at three representative axial sections. Statistical maps are thresholded at P > 0.5 (alternative hypothesis threshold for activation vs. null) and shown superimposed on the T2-weighted infant image template. The left side of the image corresponds to the left side of the brain.

Fig. 2.

Bandpassed-filtered (0.012–0.1 Hz) BOLD signal intensity time courses showing coherent spontaneous oscillations across the hemispheres for the same infant shown in Fig. 1 during rest. (A) BOLD signal intensity in the left and right sensorimotor cortex (temporal correlation coefficient, 0.73) for the same subject and resting-state network as shown in Fig. 1A. (B) BOLD signal intensity time course in the left and right posterior temporal cortex (temporal correlation coefficient, 0.81) for the resting-state network shown in Fig. 1C.

Fig. 3.

Group resting-state networks in infants. Each row shows in a coronal, sagittal, and axial view resting-state networks thresholded at P > 0.5 (alternative-hypothesis threshold for activation vs. null) superimposed on a T2-weighted infant brain image template. Consistent resting-state patterns were found in the primary visual areas (A), somatosensory and motor cortices bilaterally (B), bilateral temporal/inferior parietal cortex encompassing the primary auditory cortex (C), posterior lateral and midline parts of the parietal cortex as well as the lateral aspects of the cerebellum (D), and medial and lateral sections of the anterior prefrontal cortex (E). The left side of the image corresponds to the left side of the brain.