The 2013 Gordon Research Conference on "Cannabinoid Function in the CNS", the fifth in this series, will feature presentation of the latest findings on cannabinoid and endocannabinoid roles in neurophysiology, pathophysiology and human neurological and neuropsychiatric disorders. Participants will discuss new findings and ideas about the endocannabinoid system and its roles in synaptic plasticity and human brain function/disease states marked by alterations in neuroplasticity. Pathological processes (i.e. pain, addiction, epilepsy and neurological/neuropsychiatric disorders) linked to alterations in synaptic plasticity/endocannabinoid signaling will be evaluated from multiple levels of analysis (i.e. from molecules to man). This focus is warranted based upon widespread recreational as well as medicinal use of cannabinoid-based preparations. The conference will bring together established investigators from various disciplines, such as chemistry, biochemistry, pharmacology, physiology, imaging, neurology and psychiatry, but will also provide opportunities to young investigators and students from around of the world, with the aim of attracting new prospective leaders to this exciting research area. Poster presentations will be held on all conference days, and speakers for podium presentations will be selected from among those submitting poster presentations, to provide opportunities for early career-stage investigators to present their results to all conference attendees. All speakers will focus presentations on unpublished results, thus stressing novel/cutting edge research. In the opening keynote talk, Dr. Bernardo Sabatini (Harvard Medical School) will discuss optical methods for observing and controlling neural circuits, including work on neuromodulators, topics that are relevant to much of the work discussed throughout this meeting. Endocannabinoid roles and cannabinoid effects in the human brain will be a particular focus of the conference. Potential therapeutic uses of cannabinoids and endocannabinoid modulators will also be featured. The collegial atmosphere at the conference, with opportunities for informal gatherings during leisure time and long poster sessions, will promote cross-disciplinary discussion and collaboration with the goal of unifying different disciplines in the study of cannabinoid function in the CNS.