A 2021 study looked at attachment styles in children and how they affect brain connectivity. An attachment style, secure or insecure, is formed through interactions with a parent or main caregiver during the first three years of life and generally reflects differences in perceptions of relationships.
The researchers took a sample of 68 nine-year-old boys with secure and insecure attachment styles and used functional magnetic resonance imaging (MRI) to determine the connections in the brain critical to maintaining relationships, starting attachment behaviors and modulating reward-related processing. Researchers found that the boys with secure attachment had more connectivity in their brains, while those with insecure attachment had less functional brain connectivity. This is why it is so important for parents to build secure attachment with their small children for long term effects.