Even in carefully focused studies, however, there's still the problem of what is actually being seen. For example, no one really knows what it means when the amygdala - the brain's emotion processor and one of its most studied regions - lights up. Is it recognizing fear, anger, or happiness? Or deciding how to respond to it? Or is it merely deciding whether to respond? Despite the new fMRI technology, cognitive function remains a black box. At this point, researchers can't even say for certain whether the amygdala is activated primarily by aggression or equally by emotions like despair and joy.
The sentimentalists among us may rejoice that the human mind is still a mystery.
Side point: If you cover yourself with enough tattoos, you may not be able to have an MRI, because "tattoo ink contains trace amounts of metal, which can act like tiny lightning rods in the strong magnetic field of an MRI machine."