in the rat brain. These fibers reach and terminate in the developing Layer III and it is suggested that their early presence may play an important role in the laminar development of the prefrontal cortex (Van Eden et al., 1986). This is further supported by evidence of changes in the morphology of dopaminergic fibers beginning around postnatal day 4 (Kalsbeek et al., 1988). Thus, the rat model of third trimester alcohol exposure allows for a more direct examination of alcohol’s effects on the developing frontal cortex because many important stages of development occur after the animal is born.
