Attachment is a development milestone that can play a significant role in later psychological development (Berk, 2014). Missing this milestone can cause issues in the individual’s development. Issues in attachment can cause both behavior problems and issues with social-emotional development. Mary Ainsworth and her colleagues had a study called Strange Situation, which showed four attachment types: secure, avoidant, resistant, disorganized/disoriented. With a secure attachment, it is theorized that the positive emotions associated with the secure attachment support all aspects of psychological development (Berk, 2014). Secure attachments can also lead to more positive behaviors. Similarly, individuals with insecure attachments are theorized to be related to poor psychological development and behavior problems. Keller (2012) discusses that Ainsworth observed mothers with their infants in Uganda. Ainsworth found that mothers perceived and interpreted signals from their infants, thus acting upon these signals. If the mother acts upon these signals and fulfills the needs of the infant, the infant will form a secure attachment to their mother. This attachment will later support a strong social-emotional development.
Berk, L. E. (2014). Development through the lifespan (6th ed.). Upper Saddle River, NJ: Pearson Education.
Keller, H. (2012). Attachment and culture. Journal of Cross-Cultural Psychology, 44(2), 175–194. doi:10.1177/0022022112472253