Fig. 15.   Persistent effects of prenatal nicotine or cocaine exposure via maternal injections, or an episode of neonatal hypoxia (Slotkin et al., 1987a; Seidler and Slotkin, 1990, 1992). All three treatments evoke a lasting elevation of norepinephrine turnover, which indicates synaptic hyperactivity. These results suggest that a common factor (hypoxia-ischemia) underlies some of the similarities between the effects of nicotine and cocaine on neurodevelopment.