Adequate social stimuli, especially during childhood, are critical for future wellbeing and for the development of appropriate social and cognitive skills. Conversely, adverse social experiences in the early stages of postnatal life are associated with altered neuronal development, leading to cognitive, emotional and social impairment, greater susceptibility to the onset of psychiatric illness, such as drug addiction and eating disorders. Here, focusing on the endocannabinoid (eCB) system, we will evaluate the experience of socially impoverished or socially enriched environment during the early stages of postnatal life on the risk of developing drug addiction, eating disorders or social dysfunctions. We will explore pharmacological manipulation of, and molecular, biochemical electrophysiological, genetic and epigenetic changes in, the mesolimbic eCB neurotransmission following either social enrichment or social deprivation early in life. Finally, in compliance with the “open science” strategy and “reduction” principles for laboratory animals testing we will establish a tissue bank and an open data repository from animals used for the project.