Project Summary/Abstract The long-term goal of this research is to identify the neural mechanisms by which attention and changes in context influence the interpretation of sounds. In its simplest form, sound interpretation requires linking acoustic signals to behavioral responses. The objective of this proposal is to de- termine the contribution of distinct auditory pathways to sound-driven choices. This research will employ the mouse as a model organism and use genetic tools to identify specific cell populations according to their projection patterns. The first aim will test whether auditory thalamic and cortical circuits provide distinct acoustic information to basal ganglia regions involved in action selection. The second aim will identify the acoustic features represented by neurons from distinct basal gan- glia pathways. The third aim will test whether these neurons represent the meaning of a stimulus in addition to its acoustic features. The proposal is innovative not only in its use of genetic tools for the characterization of auditory pathways, but also in its evaluation of the role of auditory thalamic outputs to the basal ganglia. Moreover, these studies will help establish the mouse as an effective model for the study of auditory cognition, opening new avenues for detailed investigation of the neural basis of sound-driven behaviors. The proposed research is significant because it addresses es- sential steps towards identifying neural sites where context and sensory information are integrated to achieve flexible decision-making. This knowledge will greatly advance understanding of the neu- ral mechanisms underlying sound interpretation, and provide insights into how auditory cognition is affected by disease.