Does Vaginal Birth Help Hardwire the Maternal Brain?

According to this article, the brains of women who birth vaginally show more activity in response to their baby's cries than those of women whose babies were born surgically. Says one of the investigators,

Our results support the theory that variations in delivery conditions such as with caesarean section, which alters the neurohormonal experiences of childbirth, might decrease the responsiveness.

Yes, perhaps. But empirically, do we really see this? I would be curious what demonstrated behaviors, if any, correlate to the increased or decreased brain activity?

Obviously, I like any research that supports caution in using Cesarean sections. But this one seems especially primed to make women who have a C-section, including those true emergency C-sections, feel guilty. And that is the last thing any new mother needs.

update: Interestingly, a list of headlines related to this research, all cast it in negative terms (e.g. "C-Section Poses Risk to Bonding"), except one: "Natural Childbirth Makes Mothers More Reponsive to Own Baby Cry." This is my concern. The latter headline affirms vaginal* birth, while the others criticize surgical birth -- and, indirectly, the women who experience it.

*note: I, too, share the pet peeve of labeling all vaginal birth, "natural!"