NRXN3 expression in specific cerebral cortical regions and layers, especially layers 2–3 and 5–6 is documented in rodent brain atlas images [172]. While NRXN3 is also expressed in other brain regions of interest for addiction, its expression in glutamatergic projections that arise from prefrontal cortex to innervate nucleus accumbens and other striatal regions and/or in GABAergic neurons that project from cortical area to cortical area provide sites at which altered expression could readily influence circuits that are key for addictive behaviors. Alterations in the size or strength of synapses in these circuits could readily provide alteration in behavioral features, including vulnerability to addictions.
