Mechanisms for Allocating Auditory Attention: An Auditory Saliency Map

Our nervous system is confronted with a barrage of sensory stimuli, but neural resources are limited and not all stimuli can be processed to the same extent. Mechanisms exist to bias attention towards the particularly salient events thereby providing a weighted representation of our environment [1]. Our understanding of these mechanisms is still limited, but theoretical models can replicate such a weighting of sensory inputs and provide a basis for understanding the underlying principles [2, 3]. Here we describe such a model for the auditory system amp;amp;amp;amp;amp;amp;8211; an auditory saliency map. We experimentally validate the model on natural acoustical scenarios demonstrating that it reproduces human judgments of auditory saliency and predicts the detectability of salient sounds embedded in noisy backgrounds. In addition, it also predicts the natural orienting behavior of naïve macaque monkeys to the same salient stimuli. The structure of the suggested model is identical to that of succ essf ully use d vi sual saliency maps. Hence we conclude that saliency is determined either by implementing similar mechanisms in different unisensory pathways, or by the same mechanism in multisensory areas. In any case, our results demonstrate that different primate sensory systems rely on common principles for extracting relevant sensory events.