Roughly it's the base mammalian feature extractors. This can also be found by performing principal component analysis of the data, the first layer of a CNN will after training have the same representation as the PCA of the data.

The scientific opinion is that it's not a truth that works for everyone, but it's a convenient way to categorize common relationship dynamics in western, middle-class relationships.

In this specific subgroup, there is a medium correlation between the childhood and future romantic relationships. So even when looking at this specific subgroup, it's not always possible to take conclusions about someone solely from this factor.