Optimal timing for imprinting success:

Around 5 to 20 minutes following birth the baby’s eyes will stay widely open.  Within the next minute the mouth gapes and the tongue drops downwards and moves forward, signaling the mother, who is protecting her baby through skin to skin contact, of the nearing readiness to feed.

Images: Widstrom et al Acta Paediatrica 2011,100; 79

Innate goal-directed behaviour and proximity for visual accommodation provides response to the stimulus of the pigmented suckling (milking) area and baby with the evolved active participation of the mother will draw in the breast for the first immune protective feed of colostrum and learn the experience-dependent oral tactile imprint which will be reinforced through emotion and the first sleep.

Mobbs E Acta Paediatrica 2015