Sucking  as an index of mother-child interaction.
D003463:Cues; D004562:Electrocardiography; D005247:Feeding Behavior; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009034:Mother-Child Relations; D010812:Physical Stimulation; D011187:Posture; D011312:Pressure; D012677:Sensation; D013391:Sucking Behavior; D013997:Time Factors; D014059:Tongue / Q000502:physiology