“…Since then, the role that NMDA receptors play in LTP was found to extend outside of the hippocampus to anatomically early areas within the visual (Artola and Singer, 1987;Kirk et al, 2010) and auditory cortices (Kirk et al, 2010) using paradigms that include rapid, repetitive presentations of sensory stimuli (e.g., flashing visual checkerboards, trains of auditory tones). In addition, several studies have demonstrated reduced LTP in the visual and auditory cortices of individuals with mood disorders (Normann et al, 2007;Ostermann et al, 2012;Yeap et al, 2009). Taken together, these studies suggest that up-regulation of LTP via ketamine administration might serve as an important mechanistic process mediating ketamine's antidepressant effects.…”