Endogenous orienting of attention in rats

The covert orienting of attention task allows investigating the effects of spatial cues on the accuracy and speed of detection of targets. It has been extensively used in humans to investigate both attention triggered by anticipation of sensory events relying on memories of past experiences, i.e., endogenous, and attention generated by the occurrence of salient conspicuous sensory inputs, i.e., exogenous. Although this task has an analogue for rats - the three-hole nose-poke task - it has an important limitation: it uses peripheral visual cues; as these cues may engage both exogenous and endogenous attention simultaneously, it may confound phenomena associated with them. In the present study, a modified version of the task was employed, using bilateral auditory cues, which only engage endogenous orienting via a non-spatial property - pitch. Our results show that rats responded faster and more accurately when the auditory cues were informative of target location, compared to when they were not. This suggests that the task allows investigating endogenous attention in rats without confounding effects from exogenous attention. Further, this is the first unequivocal demonstration that rats can orient attention endogenously. Future studies on the neurobiology of attention may find this task useful for assessing how learned associations contribute for endogenous orienting of spatial attention in rats.