Twenty years ago, while in the middle of my PhD on implicit testing and advertising, I read an academic paper describing a variation on using millisecond reaction time (RT) to reveal unconscious biases. A few years later, the paper describing the Imp This prompted many research companies to start investigating RT based testing. I myself began using RT for brand testing around 2003 (probably the first to do this). Fifteen years on though, it's time to ask how useful actually is RT data?
With the increase in the usage of millisecond reaction time based testing this article critically evaluates the thinking behind reaction time testing, concluding that stronger definitions of what is being measured are needed and more clarity in the terminology surrounding the conscious / unconscious distinction.