The inhibitory GABAergic system also shows development during adolescence. In rats, fibers from the basolateral amygdala continue to form connections with GABAergic interneurons in the prefrontal cortex throughout periadolescence (Cunningham et al. 2002, 2008). In non-human primates, GABAergic inputs to pyramidal cells undergo changes during the perinatal period and adolescence (Akil and Lewis 1992; Cruz et al. 2003) in concert with continued maturation of behaviors mediated by the prefrontal cortex (Cruz et al. 2009). The timing of improved executive functioning and working memory performance appears to correspond with maturing GABAergic inhibitory circuits containing the protein parvalbumin (Behrens and Sejnowski 2009; Rao et al. 2000; Uhlhaas et al. 2009). In humans, the input to GABAergic interneurons in the prefrontal cortex appears to decrease strongly from adolescence to adulthood (Lewis 1997; Spear 2000).
