Lorist M M, Snel J, Kok A, Mulder G
Department of Psychonomics, University of Amsterdam, The Netherlands.
Psychophysiology. 1996 Jul;33(4):354-61. doi: 10.1111/j.1469-8986.1996.tb01059.x.
The influence of a single dose of caffeine was evaluated in focused and divided attention conditions of a visual selective search task in which subjects had to perform controlled search processes to locate a target item. Search processes were manipulated by varying display load. A dose of 3 mg/kg body weight caffeine or lactose, dissolved in a cup of decaffeinated coffee, was administered double blindly and deceptively to overnight abstinent coffee drinkers. Behavioral measures were supplemented by event-related potentials (ERPs). Subjects reacted faster in the caffeine condition. The P3b peak latency decreased after caffeine in the low display load condition and in the focused attention condition, indicating that the effects of caffeine are dependent on the number of relevant display items, not on the total number of display items presented. Search processes, as reflected in a negative ERP deflection, were not affected by caffeine.
在一项视觉选择性搜索任务的集中和分散注意力条件下，评估了单剂量咖啡因的影响，在该任务中，受试者必须执行受控搜索过程以定位目标项目。通过改变显示负荷来操纵搜索过程。将3毫克/千克体重的咖啡因或乳糖溶解在一杯脱咖啡因咖啡中，对隔夜 abstinent 的咖啡饮用者进行双盲和欺骗性给药。通过事件相关电位（ERP）补充行为测量。在咖啡因条件下，受试者反应更快。在低显示负荷条件和集中注意力条件下，咖啡因摄入后P3b峰潜伏期缩短，表明咖啡因的作用取决于相关显示项目的数量，而不是呈现的显示项目总数。如ERP负向偏转所反映的搜索过程不受咖啡因影响。
