PLoS ONE (Jan 2018)
Learned predictiveness acquired through experience prevails over the influence of conflicting verbal instructions in rapid selective attention.
Abstract
Previous studies have provided evidence that selective attention tends to prioritize the processing of stimuli that are good predictors of upcoming events over nonpredictive stimuli. Moreover, studies using eye-tracking to measure attention demonstrate that this attentional bias towards predictive stimuli is at least partially under voluntary control and can be flexibly adapted via instruction. Our experiment took a similar approach to these prior studies, manipulating participants' experience of the predictiveness of different stimuli over the course of trial-by-trial training; we then provided explicit verbal instructions regarding stimulus predictiveness that were designed to be either consistent or inconsistent with the previously established learned predictiveness. Critically, we measured the effects of training and instruction on attention to stimuli using a dot probe task, which allowed us to assess rapid shifts of attention (unlike the eye-gaze measures used in previous studies). Results revealed a rapid attentional bias towards stimuli experienced as predictive (versus those experienced as nonpredictive), that was completely unaffected by verbal instructions. This was not due to participants' failure to recall or use instructions appropriately, as revealed by analyses of their learning about stimuli, and their memory for instructions. Overall, these findings suggest that rapid attentional biases such as those measured by the dot probe task are more strongly influenced by our prior experience during training than by our current explicit knowledge acquired via instruction.