Endocannabinoid signaling in social behavior
Many animal species are social, which in many ways is essential for their survival. The neural substrates of social behavior are largely unknown, but studies on marijuana have hinted at a role for endocannabinoid signaling. We investigated this possibility using a combination of pharmacological and genetic approaches, with social place preference and social approach as readouts for social reward and social interest, respectively. The main findings of this work are: (i) oxytocin neurons in the hypothalamus recruits anandamide-mediated endocannabinoid signaling in the nucleus accumbens to regulate social reward; (ii) the endocannabinoid 2-AG is also involved in social reward but with key differences, including being generalizable to other rewards; (iii) inhibiting enzyme-mediated anandamide hydrolysis to promote its signaling may offer a viable therapeutic approach for autism-related social impairment. These findings provide important insights for larger questions in social neuroscience, including mechanisms of recruiting the endocannabinoid system, social modulation, and social development. They suggest that targeting endocannabinoid signaling may be a worthwhile approach in the treatment of social impairment, which is involved in most mental illnesses.