John Bowlby's attachment theory states that a child's early relationship with his primary caregiver or mother shapes his later development and characterizes his his human life, “from the cradle to the grave” (Bowlby, 1979, page 129). The attachment style that a child develops with his or her parents is subsequently reflected in his or her self-esteem, well-being, and the romantic relationships he or she forms. Bowlby's attachment theory was the subject of extensive research by Mary Ainsworth, who studied mother-infant interactions specifically regarding the issue of the infant's exploration of the surrounding environment and separation from the mother in an experiment called strange situation. Ainsworth defined the four attachment styles: secure, insecure/resistant, insecure/avoidant, and disorganized/disoriented, subsequently leading to research studies conducted to observe this behavior and how it affects a child into their adolescence and adulthood. The attachment style a baby endures with its mother begins before the baby is even born. In the womb, the baby becomes aware of the voices of the mother and father, where he begins to develop a bond with them and feels nourished and comforted by the things he hears his parents singing and talking. According to Bowlby, the development of attachment occurs in four different phases and is strengthened as they age: pre-attachment (from birth to 6 weeks of age), attachment in progress (from 6 weeks to 8 months of age), the attachment (from 8 months to 1 and a half years of age) and the mutual relationship (from 1 and a half or 2 years onwards). As the child grows, he begins to understand his parents' feelings and motivations and becomes able to organize his own efforts and reciprocate the same i...... middle of paper ...... as an individual , still finding a sense of closeness with their caregiver. The perceptions we form as children are progressively interpreted to structure who we are, what we do, and why we do the things we do. These long-term effects appear to grow and are constructive as internal working models that shape our behavior, self-perception, sense of self, and our expectations of other people. Works Cited Volling, B., Notaro, P., Larsen, J. (1998). Family relationships. 47, 355-367. Ainsworth, M. D. S. (1989). Bonds beyond childhood. American Psychologist, 44, 709-716.Huis in 't Veld. E., Vingerhoets. E., & Denollet. J. (2011). Elsevier Journal. 1099-1103.Hazan, C., & Shaver, P. (1987). Journal of Personality and Social Psychology e. Retrieved from http://internal.psychology.illinois.edu/~broberts/Hazan & Shaver, 1987.pdf