Infant fNIRS Resting-State Brain Imaging

While infants lay in the incubator, we acquired fNIRS signals using a multichannel NIRSport2 system (NIRStar Software v14.0, NIRx Medical Technologies LLC, Berlin, Germany) at a sampling rate of 10.17 Hz (Fig. 2). We inserted eight sources and eight detectors into predefined cap areas, with ten channels (22 mm separation) defined for each hemisphere (20 total). The optodes were placed over the prefrontal and sensorimotor regions. The first 16 sessions out of 182 used a slightly different montage, so all datasets have been merged to contain 20 out of 24 possible channels (Supplementary Fig. 1). Each light source contains two LEDs that emit at 760 nm and 850 nm. The fNIRS cap was positioned on the infant’s head according to the manufacturer’s guidelines. Resting-state fNIRS were acquired for a minimum of 2.5 min and a mean of 6.8 min^{45 (link)}.Figure 2

fNIRS acquisition system. (A) fNIRS cap. (B) NIRSport2 system. (C) Optodes.