Go Ahead and Curse! It May Ease Your Pain
It appears that the sudden outburst of profanity when you hit your thumb with a hammer (oh, like you've never done that) is not only natural but it is also a defense mechanism. It allegedly lessens the pain. Less so if swear words are not used. That's right, cussing may be "good" for you.
I am not so sure the testing the article refers to was done in a proper manner. That may be because the methodology was not detailed. Here's a quote (for those of you too lazy to click on a hyperlink and read the actual article):
The students were asked to stick their hands in buckets of icy water twice. The first time, participants repeated a curse word over and over. The next time, they repeated an everyday, neutral word.
My immediate reaction was "Did they reverse the tests with a separate group? Did they use two (or more) different groups; i.e. see if the results held up on replication?"
Another thought (I get lots of thoughts, bear with me) was that perhaps the expelling of air that comes with the swear words uttered in pain exceeds that of most benign words and that is somehow a factor. What I mean by that is that real swearing is often more forceful than the euphemistic form. I have not heard anyone shout "Drat!" as loudly or as forcibly as, say, "Damn!" (to use the mildest profanity I can think of).
I am no stranger to pain, nor to cussing when it is experienced. You do not spend four years in the Navy without learning (and becoming inured to) a full vocabulary of profanity. I have also managed over my 63 years to inflict pain on myself innumerable times (from hacking my finger with a chisel to shutting a car door on my hand and worse). I can do some pretty creative swearing at the proper moments.
Even so, I have not noticed any lessening of pain based on my reaction wording. I learned, at some point, to use a more stoic method of pain reaction. I found that the pain is quite bearable in most instances if I simply detach myself from it. This is even easier to do in situations where the pain is expected, as in the experiment described above. It's the unexpected pain that is least controllable and tends to induce an involuntary, verbal, reaction.
And I am always reminded of my father. He never once uttered a profanity in my presence. And I saw him experience great, and unexpected, pain a large number of times.
So you can put me down as a bit skeptical about this particular experiment.