Ward Ryan D, Odum Amy L
Department of Psychology, Utah State University, Logan 84322-2810, USA.
J Exp Anal Behav. 2005 Nov;84(3):401-15. doi: 10.1901/jeab.2005.94-04.
Discrepant effects of drugs on behavior maintained by temporal-discrimination procedures make conclusive statements about the neuropharmacological bases of timing difficult. The current experiment examined the possible contribution of a general, drug-induced disruption of stimulus control. Four pigeons responded on a three-component multiple schedule that included a fixed-interval 2-min, temporal discrimination, and color-matching component. Under control conditions, response rates and choice responses during the first two components showed evidence of control by time, and accuracy for color matching was high in the third component. Morphine administration flattened the distribution of fixed-interval responding and produced a general disruption of accuracy in the temporal-discrimination component, whereas accuracy in the color-matching component was relatively unaffected. Analysis of the psychophysical functions from the temporal-discrimination component indicated that morphine decreased accuracy of temporal discrimination by decreasing overall stimulus control, rather than by selectively affecting timing. These results suggest the importance of determining the neurophysiological bases of stimulus control as it relates to temporal discrimination.
药物对由时间辨别程序维持的行为产生的不同影响，使得关于计时的神经药理学基础做出确凿的陈述变得困难。当前的实验考察了药物引起的刺激控制的一般性破坏的可能作用。四只鸽子在一个三成分多重日程安排上做出反应，该日程安排包括一个固定间隔2分钟、时间辨别和颜色匹配成分。在对照条件下，前两个成分中的反应率和选择反应显示出受时间控制的证据，并且第三个成分中颜色匹配的准确性很高。给予吗啡使固定间隔反应的分布变得平坦，并在时间辨别成分中产生了准确性的普遍破坏，而颜色匹配成分中的准确性相对未受影响。对时间辨别成分的心理物理函数的分析表明，吗啡通过降低整体刺激控制而不是选择性地影响计时，降低了时间辨别的准确性。这些结果表明确定与时间辨别相关的刺激控制的神经生理学基础的重要性。
