TY - JOUR T1 - Neuronal signature of social novelty exploration in the VTA: implication for Autism Spectrum Disorder JF - bioRxiv DO - 10.1101/280537 SP - 280537 AU - Sebastiano Bariselli AU - Hanna Hörnberg AU - Clément Prévost-Solié AU - Stefano Musardo AU - Laetitia Hatstatt-Burkle AU - Peter Scheiffele AU - Camilla Bellone Y1 - 2018/01/01 UR - http://biorxiv.org/content/early/2018/03/12/280537.abstract N2 - Novel stimuli attract our attention, promote exploratory behavior, and facilitate learning. Atypical habituation and aberrant novelty exploration have been related with the severity of Autism Spectrum Disorders (ASD) but the underlying neuronal circuits are unknown. Here, we report that dopamine (DA) neurons of the ventral tegmental area (VTA) promote the behavioral responses to novel social stimuli, support preference for social novelty, and mediate the reinforcing properties of novel social interaction. Social novelty exploration is associated with the insertion of calcium-permeable GluA2-lacking AMPA-type glutamate receptors at excitatory synapses on VTA DA neurons. These novelty-dependent synaptic adaptations only persist upon repeated exposure to social stimuli and sustain social interaction. Global or DA neuron-specific inactivation of the ASD risk gene Neuroligin3 alters both social novelty exploration and the reinforcing properties of social stimuli. These behavioral deficits are accompanied by an aberrant expression of non-canonical GluA2-lacking AMPA-receptors at excitatory synapses on VTA DA neurons and an occlusion of novelty-induced synaptic plasticity. Altogether, these findings causally link impaired novelty exploration in an ASD mouse model to VTA DA circuit dysfunction. ER -