Recent research suggests that serotonergic psychedelics may simultaneously enhance connectedness to both social and natural worlds. This article synthesizes current evidence regarding psychedelics' effects on nature relatedness and social connectedness, examining underlying mechanisms through the framework of self-other overlap. Psychedelics appear to facilitate self-expansion through two complementary mechanisms: ego dissolution, which temporarily alters self-boundaries, and enhanced emotional processing, which increases empathic concern. While studies demonstrate promising effects, interpretation is complicated by methodological challenges including functional unblinding, reliance on self-reports, and small sample sizes. We propose a multidimensional model of connectedness that distinguishes between perceptual, emotional, and epistemic domains, each showing distinct patterns in acute and enduring effects. Future research would benefit from behavioral measures, active placebos, and careful consideration of contextual factors.