Examining the Relationships Between Neonatal Pain-Related Facial Actions and Cortical Activity

The current study examined the relationships between preterm and full-term neonates pain-related facial actions and cortical activity following a heel lance. Participants consisted of 41 late preterm and 37 full-term neonates, ranging in age from 0-14 days. Pain-related facial actions were micro-coded on a second-by-second basis using three constellations of facial actions to assess which is most optimal for capturing the full range of neonates pain-related facial expressions. Results indicated that a cluster of three pain-related facial actions (brow bulge, eye squeeze, and naso-labial furrow), coded on a second-by-second basis, captured the distribution in neonates pain-related facial expressions. Using this facial cluster, differences in pain-related cortical activity across the whole scalp using Global Field Power (GFP) were assessed between lower and higher pain-related facial activity. Underlying cortical activity in preterm and full-term neonates were found to vary with levels of pain-related facial activity. Implications for future research practices are discussed.