Closing the gate in the limbic striatum: prefrontal suppression of hippocampal and thalamic inputs.

Many brain circuits control behavior by integrating information arising from separate inputs onto a common target neuron. Neurons in the ventral striatum (VS) receive converging excitatory afferents from the prefrontal cortex (PFC), hippocampus (HP), and thalamus, among other structures, and the integration of these inputs is critical for goal-directed behaviors. Although HP inputs have been described as gating PFC throughput in the VS, recent data reveal that the VS desynchronizes from the HP during epochs of burst-like PFC activity related to decision making. It is therefore possible that PFC inputs locally attenuate responses to other glutamatergic inputs to the VS. Here, we found that delivering trains of stimuli to the PFC suppresses HP- and thalamus-evoked synaptic responses in the VS, in part through activation of inhibitory processes. This interaction may enable the PFC to exert influence on basal ganglia loops during decision-making instances with minimal disturbance from ongoing contextual inputs.