Early cortical sensitivity and speeded target selection underlie incidentally learned prioritization of visual features

Adaptive behavior relies on prioritizing relevant sensory information, and decades of research have shown that current task goals and stimulus saliency influence this prioritization. Recent behavioral work indicates that incidental experience with frequently relevant locations or non-spatial features also shapes behavioral prioritization. The present study investigates the neural processing stages affected by incidental learning of non-spatial visual features. We recorded neural activity with high temporal resolution using electroencephalography while human participants searched for visual targets that had predictable features (i.e. that appeared more frequently in a particular color). We found that incidental learning of the statistical structure was accompanied by an early differentiation of neural activity for relevant compared to irrelevant features beginning at 120ms post stimulus onset, followed by an earlier-onset selection of the target item, as indexed by a latency shift of the N2pc (~200ms), and changes in memory-related processes, marked by amplitude modulations of the LPC (>400ms). Importantly, the magnitude of the effects across all three neural measures strongly predicted individual differences in behavioral benefits of learned prioritization, indicating that successful learning of feature regularities depends on modulating the flow of information across multiple processing stages.