If your partner doesn’t want to see a movie with you, what pops into your head? Do you worry she might breakup with you so you text her 17 times to see if everything is ok? Are you mad because you think she’s probably blowing you off? Do you think about how she had a hard week, and she probably just doesn’t want to see a movie tonight?

When a friend doesn’t return your text immediately, how do you respond? Do you search for angry memes to send his way? Do you brood about whether he’s hanging out with his new friend from the gym? Do you acknowledge that he could be busy right now and will answer when he can?

Everyone feels varying levels of security and insecurity in their relationships, and psychologist Mary Ainsworth helps us understand why some relationships stick like new Velcro while others don’t bond.

Mary developed the Strange Situation Test and the idea of secure and insecure attachment. She discovered that when children form a healthy, secure attachment to their primary caregiver, they can then form healthy, secure attachments as adults.

In her Strange Situation Test, an infant and his caregiver are in a room when a stranger enters. The caregiver and stranger then take turns leaving the room, returning to the room, and interacting with the child.

During the test, Mary asked: How does the child explore his environment? How does the child react when the caregiver leaves? How does the child respond to the stranger? How does the child interact with the caregiver?

Mary then categorized the child and caregiver’s relationship:

  • Secure attachment—these children explored the room and stranger with confidence while returning occasionally to the safety of their caregiver.
  • Ambivalent insecure attachment—these children exhibited clingy behavior toward their caregiver.
  • Avoidant insecure attachment—these children explored the room while largely ignoring their caregivers and without their safety.
  • Disorganized/disoriented attachment—these children showed aggression toward their caregivers after their absence.

Children with a secure attachment have industrial-strength, relational Velcro. As adults, they know that one unanswered text probably means that their friend is busy, or if their partner doesn’t want to see a movie with them, their partner probably just doesn’t want to see a movie. This security allows relationships to grow and bond in healthy ways.

Mary Ainsworth (1918-1999) researched and taught at Johns Hopkins University and the University of Virginia, and you probably can’t pick up a parenting book without it referencing her work. It might be her birthday, but she has given the world the gift of understanding secure and insecure attachment. Happy birthday, Mary!

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