The touchstone of any trademark lawsuit is the likelihood of consumer confusion. Courts calculate this likelihood through a series of notoriously unreliable proxies, lamenting that their effort to understand the consumer must be a “shaky kind of guess.” Through the burgeoning field of consumer neuroscience, scientists can now determine when a subject is thinking about one brand versus another. Take, for example, recent research measuring changes in brain blood flow and oxygenation while subjects viewed several well-known trademarks. According to the researchers, each trademark has a different neural signature, with different brain regions reflecting perceptions like “excitement,” “ruggedness,” or “sophistication” upon exposure to the brand stimulus. By viewing these neural signatures and nothing else, researchers could distinguish whether the subject was thinking about Apple or Microsoft, Coke or Pepsi. Studies like this hint at a near future where fMRI readings replace today’s judicial guesswork about consumer perception.