Relative to adults, adolescents also display developmentally enhanced activity in portions of the major excitatory neurotransmitter system in brain, the glutamate neurotransmitter system and its associated N-methyl-D-aspartic acid (NMDA) receptor system (e.g., Kasanetz & Manzoni, 2009), while at the same time displaying developmental immaturity in certain components of the brain’s major inhibitory neurotransmitter system, the gamma-amino-butyric acid (GABA) system (e.g., Brooks-Kayal et al., 2001; Yu et al., 2006). These characteristics of the adolescent brain could influence adolescent responsiveness to alcohol as well, given that alcohol-related blockade of glutamate NMDA receptor action and stimulation of GABA systems are thought to be critical for contributing to the intoxicating effects of alcohol (see Eckardt et al., 1998; McBride & Li, 1998). Indeed, as discussed below, adolescents differ markedly from adults in their sensitivity to a variety of effects of alcohol.
