This grant supports the Independent Phase of an NIH Pathway to Independence Career Development Award. The goal of this proposal is to extend the understanding of decision-making beyond the simple paradigms that have been studied thus far. During the mentored phase, the investigator used an experimental and theoretical approach to examine how subjects integrate sensory evidence for simple decisions. This study will explore how animals integrate evidence for more complex decisions- in particular, decisions where the sensory evidence comes not only from the visual system (single cue decisions), but from the auditory system as well (cue integration decisions). While it has been known for some time that vision can be influenced by other modalities, the neural mechanisms underlying this phenomenon remain largely unknown. To investigate the neural mechanisms underlying cue integration, the investigator will use a rate discrimination decision task to examine how the speed and accuracy of animal subjects' decisions changes depending on whether rate information is presented to the visual system, the auditory system, or both. Because the information about rate in the task is noisy and unreliable, animals can potentially make better decisions if they integrate information from the two modalities. Further, the investigator will record brain activity by measuring electrophysiological responses from parietal cortex as the animals are engaged in the task. This approach can help answer whether differences in decision speed and accuracy on the single-cue versus cue integration tasks be explained by the different electrophysiological responses on the two tasks.