Stewart Robert B, Wang Nian-Sheng, Bass April A, Meisch Richard A
University of Texas Houston, Health Science Center, USA.
J Exp Anal Behav. 2002 Jan;77(1):49-64. doi: 10.1901/jeab.2002.77-49.
The relative reinforcing effects of different doses of orally delivered ethanol were evaluated. Mouth-contact responding by rhesus monkeys was measured under concurrent fixed-ratio fixed-ratio schedules of liquid delivery (0.67 ml/delivery) from each of two spouts during daily 3-hr sessions. Experiment 1 examined persistence of responding with ethanol (2%, 8%, and 32% wt/vol) and water available. When fixed-ratio values from 8 to 128 were tested, the number of ethanol deliveries obtained per session decreased as the response requirement increased. The decrease in deliveries was less at higher than at lower ethanol concentrations, however. Experiment 2 examined choice between two ethanol concentrations under concurrent fixed-ratio 16 schedules (4% vs. 8%, 4% vs. 16%, 8% vs. 16%, 2% vs. 8%, 2% vs. 32%, 8% vs. 32%). Higher concentrations (16%, 32%) generally maintained more responding than concurrently available concentrations of 8% or less. An exception was the observation of a preference for 8% over 32% ethanol. When the fixed-ratio value was increased, however, the relative preference for these two doses was reversed so that 32% ethanol maintained more responding than 8% ethanol. Thus, the direction of the preference depended on the size of the response requirement. These results indicate that the reinforcing effects of ethanol increase with dose.
评估了经口给予不同剂量乙醇的相对强化作用。在每日3小时的实验时段内，恒河猴的口接触反应在来自两个喷嘴的液体递送（每次递送0.67毫升）的并发固定比率固定比率时间表下进行测量。实验1研究了在有乙醇（2%、8%和32%重量/体积）和水的情况下反应的持续性。当测试从8到128的固定比率值时，每次实验获得的乙醇递送次数随着反应要求的增加而减少。然而，在较高乙醇浓度下递送次数的减少幅度小于较低乙醇浓度下的减少幅度。实验2研究了在并发固定比率16时间表下两种乙醇浓度之间的选择（4%对8%、4%对16%、8%对16%、2%对8%、2%对32%、8%对32%）。较高浓度（16%、32%）通常比较低或等于8%的并发可用浓度维持更多的反应。一个例外是观察到对8%乙醇的偏好超过32%乙醇。然而，当固定比率值增加时，这两种剂量的相对偏好发生逆转，使得32%乙醇维持的反应比8%乙醇更多。因此，偏好的方向取决于反应要求的大小。这些结果表明乙醇的强化作用随剂量增加。
