Human beings have a natural tendency to form attachment bonds once they are born. Some authors believe this is motivated by a need for survival. What is interesting, however, is that the quality of attachment doesn't seem to be driven so much by the existence of a primary giver who feeds and changes the baby but more by a figure who communicates and plays with the child to some extent. In other words, healthy attachment occurs when there is a sensitive responsiveness to the baby's needs. This has been also found in a very interesting experience conducted by Harlow.