PT - JOURNAL ARTICLE AU - Jaramillo, Santiago AU - Borges, Katharine AU - Zador, Anthony M. TI - Auditory Thalamus and Auditory Cortex Are Equally Modulated by Context during Flexible Categorization of Sounds AID - 10.1523/JNEUROSCI.4888-13.2014 DP - 2014 Apr 09 TA - The Journal of Neuroscience PG - 5291--5301 VI - 34 IP - 15 4099 - http://www.jneurosci.org/content/34/15/5291.short 4100 - http://www.jneurosci.org/content/34/15/5291.full SO - J. Neurosci.2014 Apr 09; 34 AB - In a dynamic world, animals must adapt rapidly to changes in the meaning of environmental cues. Such changes can influence the neural representation of sensory stimuli. Previous studies have shown that associating a stimulus with a reward or punishment can modulate neural activity in the auditory cortex (AC) and its thalamic input, the medial geniculate body (MGB). However, it is not known whether changes in stimulus–action associations alone can also modulate neural responses in these areas. We designed a categorization task for rats in which the boundary that separated low- from high-frequency sounds varied several times within a behavioral session, thus allowing us to manipulate the action associated with some sounds without changing the associated reward. We developed a computational model that accounted for the rats' performance and compared predictions from this model with sound-evoked responses from single neurons in AC and MGB in animals performing this task. We found that the responses of 15% of AC neurons and 16% of MGB neurons were modulated by changes in stimulus–action association and that the magnitude of the modulation was comparable between the two brain areas. Our results suggest that the AC and thalamus play only a limited role in mediating changes in associations between acoustic stimuli and behavioral responses.