Environmental enrichment as an experience-dependent modulator of social plasticity and cognition.

Social plasticity is the ability to adaptively change the expression of social behaviour according to experience, allowing animals to optimize their social relationships in the context of previous experience and the complexities of social environments. Environmental enrichment (EE) mimics a stimulating lifestyle at the laboratory level and has demonstrated beneficial effects on various aspects of brain structure, function, behaviour and cognition. EE has also been shown to induce neuroprotection and functional compensation that is therapeutic in a range of different brain disorders. The effects of EE on social plasticity have received little attention, despite the fact that many components of the mechanisms of social plasticity and EE-induced plasticity are overlapping. We review and discuss EE effects on social plasticity, with a focus on laboratory rodent studies. This review presents evidence that EE affects social plasticity, via both direct and indirect mechanisms, as well as under pathological conditions. In conclusion, EE is a valuable tool to study social cognition and behaviour, and could inform therapeutic approaches to the many brain disorders involving social dysfunction, including schizophrenia and autism spectrum disorders.