This article only focuses on the human subjects. But that's not all of neuroscience.

There are different reasons to prefer one gender over the other in experiments with animals. For example, female rodents are easier to handle and less aggressive so they are preferred in behaviour studies but they are also hormonally more complex than male rodents which can interact with biological signals that you are measuring. Furthermore, some studies are done over both genders so that their final results can be reported to be true independent of gender. So it really depends on what one is trying to study and to what level gender can or can not affect that study.