title: Neonatal smiling, frowning, and rapid eye movement states. II. Sleep-cycle study.
mesh_terms: D000367:Age Factors; D002652:Child Behavior; D003210:Concept Formation; D003448:Crying; D005149:Facial Expression; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010507:Periodicity; D012894:Sleep Stages; D012895:Sleep, REM; D013997:Time Factors