The brain makes a distinction between hard and easy stimuli: comments on Beretta et al.

The Beretta et al. study tested an invalid prediction concerning connectionist models of inflectional morphology and the study exhibits a confound between type of stimulus (regular, irregular) and processing difficulty (easy, hard) that invalidates their conclusions. Harder stimuli produced greater activation across a broader range of brain areas, as in previous studies, but the data have no bearing on the rules vs. connections debate.