I am convinced that this article is correct in its assumption. Speaking anecdotally, I usually tend to remember written word better than typed. This article gives sufficient evidence for me to believe its claim, but keep in mind I am biased. The biggest piece of information for me was the reference to the fact that this affects adults as well as children. It is well known that children have slightly different working brains than us, so it is important that the distinction is made. The only thing I am not convinced of is the long term effects on children. Does the fact that these children are not taught handwriting affect their adult hood? There is no evidence to show for that in this article. The study only refers to children during childhood and adults during adulthood, but does not even seem to test long term effects.
I would say that this commercial source would be good enough for my research paper. I get a feeling from the generally tone of the article that the author is taking a stance in favor of more handwriting to be taught in schools. It may be a little biased, as indicated by the tone of the article, but it references a study from reliable university scientists to borrow credibility from their respected status. It is a fairly current article, and if I was doing a topic relating to handwriting it would be relevant. Its purpose is to find out, as the title indicates, what we are losing in our minds as we move away from handwriting. The Everyday Writer says to question the publisher of this article. The New York Times is a proven and well respected magazine throughout the US. I would wager that they have some kind of fact checking depart to prevent them from losing credibility. Because of these reasons, I would use this source in a research paper if it was relevant to my topic.