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Bariselli, S.

Publications and source records attributed to Bariselli, S..

2 recordsLinked to original sources

SHANK3 downregulation in the VTA accelerates the extinction of contextual associations induced by non-familiar conspecific interaction

Conditioned place preference (CPP) paradigms, traditionally adopted to study the reinforcing properties of drugs of abuse, have been developed to investigate the neurobiological mechanisms underlying the reinforcing properties of social stimuli. These protocols are largely based on single-housing before and/or during the social stimulus-contextual cues acquisition phase. Here, based on previously established social interaction-induced CPP paradigms, we characterize a place preference task relying on the reinforcing properties of free interaction with a non-familiar (novel) conspecific. The formation of contextual associations induced by the interaction with a novel social stimulus does not require single-housing, necessitates dopamine (DA) receptor 2/3 (D2/3R) activation and undergoes extinction. Interestingly, while extinction of CPP responses is reduced by single-housing, it is accelerated by the downregulation of the autism spectrum disorder (ASD)-related protein SHANK3 in the ventral tegmental area (VTA). Thus, inspired by the literature on drug of abuse-induced contextual learning, we propose that acquisition and extinction of CPP might be used as behavioral assays to assess social-induced contextual association and \"social-seeking\" dysfunctions in animal models of psychiatric disorders.

neuroscience

Neuronal signature of social novelty exploration in the VTA: implication for Autism Spectrum Disorder

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.

neuroscience