There is much evidence from neuroscience that the brain wiring that develops in this context and remains in the brain is particularly resistant to change through the normal process of neural plasticity. While it is true that later in childhood and adolescence the number of these connections is greatly reduced through a process called pruning, I suspect the ones that are lost are those that are not continually reinforced by the attachment figures.
Serve and return was further explained as interactions that shape brain architecture: "When an infant or young child babbles, gestures, or cries, and an adult responds appropriately with eye contact, words, or a hug, neural connections are built and strengthened in the child’s brain that support the development of communication and social skills. Much like a lively game of tennis, volleyball, or Ping-Pong, this back-and-forth is both fun and capacity-building. When caregivers are sensitive and responsive to a young child’s signals and needs, they provide an environment rich in serve and return experiences."