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 Implicit Association Test (IAT) (Greenwald et al 1998) was highlighted in Malcolm Gladwell's (2005). book Blink. 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?

Problems with RT Test

Is what it measures Unconscious? Subconscious? Non<onsdous? Preconsdous? Implicit?

For years, marketers and advertisers have talked about "The Unconscious" (or Subconscious). What they usually mean is derived from Freudian idea of a "brain inside a brain" (called the homunculus) that drives behavior without awareness. However, no evidence, psychological or neuroscientific, has ever been found of its existence. This description is still used in the arts & humanities metaphorically, to account for various phenomena, and remains the most popular description of unconscious mental processes. But the lack of any real evidence of its existence unfortunately means most people's understanding of non-conscious processes is incorrect.