In vivo experiments present anatomically selective neurochemical effects of modafinil on monoaminergic units (de Saint Hilaire et al 2001; Ferraro et al 2002), and, notably, although modafinil boosts TMN fos expression (Scammell et al 2000) and HAergic tone it is unable to exert this effect when administered directly to the TMN (Ishizuka et al 2003