TY - JOUR TI - Two-photon imaging in mice shows striosomes and matrix have overlapping but differential reinforcement-related responses AU - Bloem, Bernard AU - Huda, Rafiq AU - Sur, Mriganka AU - Graybiel, Ann M A2 - Schoenbaum, Geoffrey VL - 6 PY - 2017 DA - 2017/12/18 SP - e32353 C1 - eLife 2017;6:e32353 DO - 10.7554/eLife.32353 UR - https://doi.org/10.7554/eLife.32353 AB - Striosomes were discovered several decades ago as neurochemically identified zones in the striatum, yet technical hurdles have hampered the study of the functions of these striatal compartments. Here we used 2-photon calcium imaging in neuronal birthdate-labeled Mash1-CreER;Ai14 mice to image simultaneously the activity of striosomal and matrix neurons as mice performed an auditory conditioning task. With this method, we identified circumscribed zones of tdTomato-labeled neuropil that correspond to striosomes as verified immunohistochemically. Neurons in both striosomes and matrix responded to reward-predicting cues and were active during or after consummatory licking. However, we found quantitative differences in response strength: striosomal neurons fired more to reward-predicting cues and encoded more information about expected outcome as mice learned the task, whereas matrix neurons were more strongly modulated by recent reward history. These findings open the possibility of harnessing in vivo imaging to determine the contributions of striosomes and matrix to striatal circuit function. KW - striosome KW - striatum KW - 2-photon imaging KW - reinforcement learning KW - basal ganglia JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -