I too find the research about the 'brain damage' unconvincing. It seems melodramatic. Many posters have posted various links, but none of it deals with this specifically.
You can't compare the different studies. One is re very neglected children who had minimal human intervention or care. Another is rats. Another supposedly is babies who weren't cared for and some went on to die.
None of these relate to children of loving parents, who are very attentive to their children, but then leave them to cry for an hour.
Not that I'm recommending that anyone does!
Ds2 was colicky, and cried from 6pm through to 4am, off-and-on, sometimes sleeping for an hour or so, sometimes crying in my arms for hours. He was inconsolable. This went on every night for months. Bought me to my knees. I told the HV many times, went to GP, paid to see a private paediatrician. All very dismissive.
But in this discussion, as soon as someone mentioned colic, people said oh no, that doesn't apply, its only if they are left on their own, that it causes brain damage.
Well the original article didn't make that clear. So it seems a bit scaremongering, with a huge headline, meant to scare.
Maybe I'm being over sensitive because of the Ds2 colic thing.