How to tell if a brain region really cares about faces or just their edges?

Neuroscientists locate which brain regions handle visual concepts (faces, places) by finding areas that activate strongly for those concepts. But activation alone doesn't prove representation—a face region might just respond to skin texture or lighting. BrainCause combines generative AI and brain imaging models to synthesize counterfactual stimuli (faces with specific features removed) and test whether regions respond to the actual concept or correlated visual quirks. On predicted and real fMRI data, the method recovered known localizations and identified new ones, while showing most activation-only findings are false positives.