A study with only 32 subjects is statistically worthless.
Are you a statistician? I'm not.
If you have a normal distribution in a population, that may seem to be a tiny sample, but if there is a biphasic distribution according to gender, the results seem intriguing at the least.
Revenge 'more satisfying for men'
When the "fair" players were shocked, both female and male volunteers showed increased activity in the pain-related centres of the pain - the fronto-insular and anterior cingulate cortices.
When the "unfair" actor received a shock, the women taking part in the experiment showed a similar empathy with them.
In contrast, the male volunteers showed no increased activity in the empathy-related pain areas.
They did, however, show a surge of activity in the reward centre of the brain - the nucleus accumbens.
P.S. When I worked in Quality Control for Wella AG, a medium sized, hair care products company two decades ago, filling weights were usually checked with two dozen samples for each lot whose usual total daily production numbered about 3,000 - 5,000 units.
The reference to the actual article is Nature (DOI: 101038/nature04271). I'm going to the library to see if I can locate the abstract and an associated P value.