It's entirely possible that the results in those studies you provided are solid. I don't know, I don't have the expertise or the access to go through them thoroughly, let alone run a replication. I would just urge everyone here to keep in mind that, as pointed out very well in aestra's comment above (https://news.ycombinator.com/item?id=7213317), this kind of research is subject to heavy cultural biases, both through the parents and experiments and through poor science reporting in the media.
And, even if it weren't, this Live Science linkbait blog post, the one rapidly climbing the front page of Hacker News with the sensationalist headline, is still uncited bollocks.