A newborn presents with jaundice within the first 24 hours o…

A newborn presents with jaundice within the first 24 hours of life and a bilirubin level of 22 mg/dL. Given the early onset and severity of hyperbilirubinemia, which complication is most concerning due to bilirubin crossing the immature blood-brain barrier and depositing in basal ganglia and brainstem nuclei?