Bowlby suggests that humans have an innate tendency to form attachments to their primary caregiver, most likely their mother. He proposed 6 characteristics which explain attachment:
Adaptive
Social releasers
Critical period
Monotropy
Internal working model
Critical Period - This refers to the idea that there is a specific time, 2 and a half years when infants can form an attachment by, otherwise they may not be able to later in life.
Adaptive - Bowlby suggested that the ability to form attachments is adaptive as it helps us survive by ensuring we are cared for
Social releasers - These are behaviours that trigger responses from others such as crying or smiling. They allow infants to communicate with adults and ensure they receive attention.
Monotropy - The idea that children only form one strong attachment with their main carer (usually the mother).
Internal Working Model - A mental representation or schema of how we perceive ourselves and others around us. It can influence our future relationships as it provides a template for what we expect from them.