Levens Neil, Akins Chana K
Department of Psychology, Indiana University of Pennsylvania, Indiana, PA 15705, USA.
Pharmacol Biochem Behav. 2004 Nov;79(3):451-7. doi: 10.1016/j.pbb.2004.08.021.
Repeated drug exposure that results in behavioral sensitization has been shown to enhance sex-seeking behaviors in rats as well as facilitate Pavlovian excitatory and inhibitory conditioning. In the present experiment, male Japanese quail were given repeated presentations of cocaine (10 mg/kg, i.p.) that resulted in increased locomotor activity relative to saline. After a 10-day withdrawal period, subjects received sexual conditioning trials that consisted of presentation of an object conditioned stimulus (CS) followed by sexual reinforcement. Results showed that birds that previously received chronic cocaine demonstrated more conditioned approach behavior to the CS object, a shorter latency to copulate with a female, and made more cloacal contacts (copulatory behavior) during sexual reinforcement than saline-treated birds. The findings suggest that chronic cocaine later facilitates Pavlovian conditioning in a sexual behavior paradigm. This may be the result of cocaine facilitating learning via the dopaminergic system. The findings are discussed in the context of the incentive sensitization theory and possible neuronal mechanisms.
反复药物暴露导致行为敏感化,已被证明会增强大鼠的求偶行为,并促进巴甫洛夫兴奋性和抑制性条件反射。在本实验中,雄性日本鹌鹑反复接受可卡因(10毫克/千克,腹腔注射),相对于生理盐水,这导致其运动活性增加。经过10天的戒断期后,实验对象接受性条件反射试验,该试验包括呈现一个物体条件刺激(CS),随后进行性强化。结果表明,先前接受慢性可卡因处理的鸟类对CS物体表现出更多的条件性接近行为,与雌性交配的潜伏期更短,并且在性强化过程中比接受生理盐水处理的鸟类有更多泄殖腔接触(交配行为)。研究结果表明,慢性可卡因后来在性行为范式中促进了巴甫洛夫条件反射。这可能是可卡因通过多巴胺能系统促进学习的结果。研究结果在动机敏感化理论和可能的神经元机制的背景下进行了讨论。