These opportunities have led to infringements and, in turn, to laws to regulate and control. The courts in their turn have had to interpret and administer the laws. Even fifty years ago, the courts might have been forgiven for not turning to the reality of the market place to find the degree to which confusions and the like actually existed. Judges and regulators decided whether substantive infringement had occurred based on their mental models of what other people might perceive. Given the tremendous developments in cognitive theory and methodology over the last 50 years, it is no longer reasonable to make such judgments in the absence of data about what actually happens in the relevant marketplace.
Confusion is no longer a matter of speculation or subjective impression by judges.
Instead it must be demonstrated. Modern techniques and statistical models make it possible to obtain quantitative data about the degree of similarity and confusability of two marks or names in the laboratory. As these techniques become validated in the field the use of preliminary laboratory measurement will grow and the difficulty of fieldwork diminish. The techniques of the behavioral laboratory and the very specific demands of the law for demonstration of hitherto ill-defined and hypothetical behaviors have produced a new kind of field experiment drawn from the laboratory to answer questions relevant to the law. The courts, and the law, will inevitably follow, albeit with some delay, the new human cognitive sciences.