The effect of chronic cocaine exposure during pregnancy on the acquisition of operant behaviors by rhesus monkey offspring

To explore possible long-term effects of gestational cocaine exposure in a nonhuman primate model, pregnant rhesus monkeys were treated from about 1 month of gestation until term with either 0 (N = 3), 0.3 (N = 3), 1.0 (N = 3), or escalating doses up to 8.5 (N = 3) mg/kg (IM), three times per day, 5 consecutive days per week. Despite these differences in cocaine exposure, the experimental groups did not differ significantly with respect to the postnatal growth of offspring over an 18-month period following birth. Beginning at 6 months of age, the behavior of offspring was monitored using an operant test battery that included five food reinforced tasks designed to model aspects of learning, color and position discrimination, rime estimation, short-term memory and attention, and motivation. Although the acquisition of each operant behavior by offspring progressed significantly during training between 6 and 18 months of age, this acquisition was not differentially affected by gestational cocaine exposure. It was concluded that, in a rhesus monkey model, chronic cocaine exposure during pregnancy had no significant effect on the offsprings' acquisition of operant behaviors.