Archives for cognitive development



“Our Solar System Is a Bit of a Freak”

In a paper to be published in Astronomy & Astrophysics, researchers say they have found that “Tau Ceti, one of the closest and most Sun-like stars, may host five planets, including one in the star’s habitable zone.”

Very interesting quote from Steve Vogt, a professor of astronomy and astrophysics at UC Santa Cruz, who is one of the paper’s authors:

“We are now beginning to understand that nature seems to overwhelmingly prefer systems that have multiple planets with orbits of less than 100 days. This is quite unlike our own solar system, where there is nothing with an orbit inside that of Mercury. So our solar system is, in some sense, a bit of a freak and not the most typical kind of system that Nature cooks up.”

This is, among other things, a good reminder that the local patterns you are familiar with are not necessarily representative of the broader world (or universe!). It is easy, and tempting, to assume that the politics/family dynamics/fill-in-the-blank that you see around you daily is common elsewhere; but often, it’s simply not.



The Disadvantages of Summer Babies

A new report from the Institute of Fiscal Studies in the U.K. examines the big difference that a few months can make in the student achievement of young children. Authors Claire Crawford, Lorraine Dearden and Ellen Greaves found (along with several previous studies, like this one and this one) that children born in summer months generally score lower on standardized tests and are seen as “underachievers;” while children born in September and autumn months are more academically and socially successful. Read More »



Is Extra Maternity Leave Bad for Child Cognitive Development?

Back in March we wrote about a Norwegian study which showed that an increase in maternity leave led to lower high-school dropout rates for the children of those moms. But a new working paper about maternity leave in Canada (abstract here) highlights some possible negative effects of extra maternity — specifically on a child’s cognitive development at ages 4 and 5. At issue isn’t the extra time a mother spends with her child, but the timing of when she returns to work, and the abrupt change it causes.

Michael Baker of the University of Toronto and Kevin Milligan of The University of British Columbia focused their research on a Canadian law passed at the end of 2000 that extended maternity leave from 6 months to a full year. As a result, the timing of the return to work changed from an average of just under 6 months to nearly 9 months:

We find that the expansion of parental leave — and the resulting extra time mothers spent with their child in his/her first year of life—had no positive impact on indices of children’s cognitive and behavioral development; this despite the fact it had substantial impacts on the maternal care and non-licensed non-parental care children received in their first year, as well as how long they were breastfed. For our behavioral indices we can rule out all but very modest improvements. For our cognitive measures the estimated impact of the reform is small, negative and statistically significant for PPVT and Who Am I? This latter result highlights the relatively neglected issue of how changes in maternity leave laws affect the timing of the mothers’ return to work. Specifically, it is consistent with the hypothesis that some ages are better than others for abrupt changes in the parent-child relationship.