“…Strongly dependent on glutamatergic signaling, MMN is attenuated in rats, monkeys and healthy adults with high-affinity NMDA (N-methyl-Daspartate)-type glutamate receptor antagonists (Javitt et al, 1996;Tikhonravov et al 2008;Umbricht et al 2000) such as ketamine which, when combined with nicotine, fails to disrupt MMN in some but not all investigations (Mathalon et al 2014). Most frequently investigated in healthy participants with frequency deviants, nicotinic stimulation has resulted in negative (Knott et al 2006, diminishing (Knott et al 2009) and enhancing effects on MMN amplitude (Dunbar et al 2007), with the latter positive outcome also being shown with pattern (Baldeweg et al 2006), temporal (Martin et al 2009) and visual deviants . Such response variability is also seen in the relatively few studies in SZ, with nicotine not affecting frequency deviant MMN (Dulude et al 2010;Inami et al 2007), shortening latency of intensity-deviant MMN ) and in our work, "normalizing" durationdeviant MMN by increasing the diminished MMN in patients to a level comparable to that seen in healthy volunteers (Dulude et al 2010).…”