Practice does make perfect: On the interaction of perceptual load, cognitive load and attentional training in visual search

Lavie, Hirst, Fockert and Viding (2004) hypothesise that the level of attentional selection is determined based on the interaction of cognitive and perceptual load. When perceptual load is low, there are surplus processing resources that automatically “spill over” onto irrelevant information and when perceptual load is high, all available resources are devoted to target processing preventing the analysis of irrelevant information. Conversely, when cognitive load is high, the control of attention is impaired, and as a result irrelevant information is processed. In comparison, when cognitive load is low, attention can be efficiently focused on relevant items, thus limiting the analysis of irrelevant stimuli. Load theory makes a key prediction that with attentional training, perceptual load tasks should become easier, require fewer processing resources and in turn lead to greater analysis of irrelevant information. Yet to date only Wilson, Macleod and Muroi (2008) have examined how training interacts with perceptual load to determine selective attention performance, finding mixed results with respect to load theory's predictions. In addition, Wilson et al. (2008) only examined perceptual load within their task, and failed to take into account how cognitive load could also interact with training. Here we investigated how training interacts with both cognitive and perceptual load within a typical attentional load paradigm. No evidence of increased flanker interference with training was observed after varying levels in both cognitive and perceptual load. These results suggest that Lavie et al.'s (2004) model requires revision, as one of its key predictions could not be empirically demonstrated