John Bowlby's attachment theory, first proposed between 1958 and 1960, explores the dual nature of attachment - biological and cognitive.

• Biological aspects: Known as the 'attachment behavioural system,' this involves instinctive behaviours that occur in response to environmental cues. Think of a baby sensing danger and immediately crying for its caregiver, or an antelope sensing a predator and running. This is the 'alarm' mode. Another mode is 'anxiety,' like a child anticipating a scary doctor's visit. Both modes compel the individual to seek comfort from the caregiver.

• Cognitive aspects: Referred to as the 'internal working model,' this involves our beliefs and mental images about attachment. This includes beliefs about oneself, others, and the nature of relationships. For example, a child who consistently receives attention may grow to believe they are valued and worth the attention of others. Conversely, a child who is neglected or overly pampered might develop unhealthy expectations of relationships.

Example: Consider a young child named Lily. Lily's parents always comfort her whenever she's scared or anxious (biological aspect). Over time, Lily learns that her parents will always be there to protect and support her (cognitive aspect).

• Critical Period of Attachment: According to Bowlby, the critical period for forming attachments is between 6 months and 3 years. If an attachment is not formed during this window, it may never form. This concept has been somewhat revised in subsequent research.

• Irreversibility of Attachment: Bowlby also claimed that the effects of attachment are permanent. This view, too, has been revised in later research.