“…Initial research on second-generation antipsychotics generated hope for therapeutic effects to extend into the cognitive domain, but yielded no consistent evidence thereof (Beninger et al, 2010). Other drug classes have been investigated as possible augmentation therapies, such as nicotinic and muscarinic acetylcholine receptor agonists (Martin and Freedman, 2007;Radek et al, 2010;Sellin et al, 2008;Hong et al, 2011), cholinesterase inhibitors Stip et al, 2007), NMDA and AMPA receptor ligands (Goff et al, 2008a(Goff et al, , 2008bLieberman et al, 2009), a D1 agonist (George et al, 2007), a 5-HT3 antagonist (Akhondzadeh et al, 2009), and the analeptic drug Modafinil (Saavedra-Velez et al, 2009). Despite reports of small benefits, no pharmacological add-on strategy has obtained convincing clinical support (Zink et al, 2010).…”