The present invention provides methods for treating social anxiety disorder, comprising administering 2-(7-chloro-1,8-naphthyridin-2-yl)-3-(5-methyl-2-oxo-hexyl)-1-isoindolino- ne or 2-(7-chloro-1,8-naphthyridine-2-yl)-3-(5-methyl-5-hydroxy-2-oxohexyl- ) -1-isoindolinone or pharmaceutically acceptable salt, or optical isomer therof, and optionally comprising administering another compound for the treatment of social anxiety disorder that is a GABA agonist.