For psychologists, the standard view of children’s attachment is that the ways that a parent acts causes the child to react with differing styles and levels of emotional attachment. But there is now a challenge this model, arguing that it does not take into account intelligence and the genetic transmission of behavior from parent to child.
The authors’ model is that the parent’s intelligence is an ultimate cause of the child’s attachment and that the child’s intelligence also has an impact on their behavior. In short, smarter parents have more stable and positive attachment styles to their children, and smarter children discern better how to respond to parental behavior (good or bad). You can see diagrams showing the similarities and differences in the two models below.
The new model also acknowledges that some of the similarities between a parent’s and a child’s behavior can be caused by shared genes and environment between the child. That would mean that some child behaviors aren’t caused by the parent’s behavior at all. Adherents to the standard model often ignore genetic transmission of behavior.
There is a lot of evidence the authors present for their model. Much of it comes from the research in intelligence and behavioral genetics. The authors summarize it below.
It is important to recognize that this model is in the proposal stage. There needs to be more research and data to test it. Incorporating child and parent IQ into more studies on attachment is essential, as are genetically sensitive designs (e.g., adoption studies). But the model seems plausible, and scientists will learn a lot by pitting it and the standard model against each other to see which one makes better predictions.
This challenges a fundamental assumption in developmental psychology that parent behavior alone shapes attachment. The key insight is that intelligence affects both how parents respond to children and how children interpret parental behavior. Smarter parents might be better at reading infant cues, regulating their own emotions, and providing consistent caregiving. Smarter children might be better at understanding parental intentions even when behavior is inconsistent. The genetic correlation between parent and child IQ creates a confound that attachment research has largely ignored. This doesn’t mean parenting doesn’t matter, but it suggests we’ve been overestimating its causal role by ignoring shared genetics.
The implications are pretty significant if this model holds up. It would mean that some kids develop insecure attachment not primarily because of bad parenting, but because lower cognitive ability makes them less able to navigate complex social cues or regulate emotional responses. Similarly, some of what we attribute to sensitive parenting might actually reflect higher parental IQ enabling better problem solving, perspective taking, and emotional regulation. The genetic transmission piece is crucial because twin and adoption studies could test this directly. If attachment patterns are partly heritable independent of parenting quality, that would reshape intervention strategies.
