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Huda, R.

Publications and source records attributed to Huda, R..

2 recordsLinked to original sources

Bidirectional control of orienting behavior by distinct prefrontal circuits

Sensorimotor behaviors require processing of behaviorally relevant sensory cues and the ability to select appropriate responses from a vast behavioral repertoire. Top-down modulation by the prefrontal cortex (PFC) is thought to be key for both processes but the precise role of specific circuits remains unclear. We examined the sensorimotor function of anatomically distinct outputs from a subdivision of the mouse PFC, the anterior cingulate cortex (ACC). Using a visually guided two-choice behavioral paradigm with multiple cue-response mappings, we dissociated the sensory and motor response components of sensorimotor control. Projection-specific two-photon calcium imaging and optogenetic manipulations show that ACC outputs to the superior colliculus, a key midbrain structure for response selection, principally coordinate specific motor responses. Importantly, ACC outputs exert top-down control by reducing the innate response bias of the superior colliculus. In contrast, ACC outputs to the visual cortex facilitate sensory processing of visual cues. Our results ascribe motor and sensory roles to ACC projections to the superior colliculus and the visual cortex and demonstrate for the first time a circuit motif for PFC function wherein anatomically non-overlapping output pathways coordinate complementary but distinct aspects of visual sensorimotor behavior.

neuroscience

Two-Photon Imaging of Striatum Demonstrates Distinct Functions for Striosomes and Matrix in Reinforcement Learning

Despite the discovery of striosomes several decades ago, technical difficulties have hampered the study of their functions. Here we used 2-photon calcium imaging in neuronal birthdate-labeled Mash1-CreER mice to image simultaneously the activity of striosomal and matrix neurons in vivo. We report that with this method we can visually identify circumscribed zones of neuropil that correspond to striosomes as verified in immunostained sections. We find that striosomal neurons, relative to matrix neurons, preferentially encode reward-predicting cues, and that their activity contains more information about expected outcome. These characteristics emerge during training and further strengthen during overtraining. Both striatal compartments are active similarly after reward delivery, firing at neuron-specific times during or after consummatory licking. Finally, we find that immediate reward history strongly modulates neuronal activation in the next trial, especially in matrix neurons. These results suggest that striosomes and matrix have distinct functions in relation to reinforcement learning.

neuroscience