Tsiora Stamatina, Potter Douglas D, Kyle John S, Maxwell Adele M
School of Psychology, University of Dundee, Dundee DD1 4HN, UK.
Psychiatry J. 2013;2013:823158. doi: 10.1155/2013/823158. Epub 2013 Jun 16.
Nicotine's attention enhancing effects are often attributed to enhancement of stimulus filtering by the attention networks. We investigated distractibility in 20 abstinent cigarette smokers (9 hours overnight; phase 1) and tested them again after smoking one cigarette (phase 2). Their performance was compared to 20 nonsmokers (no nicotine intake). In an auditory number parity decision task, participants had to make a forced choice "odd" or "even" decision about centrally presented numbers between 2 and 9, while ignoring laterally presented preceding or simultaneous novel distractors. In phase 1, distractors that preceded goal stimuli slowed reaction times (RTs) more than simultaneously presented distractors in both groups. In phase 2, nicotine intake speeded RTs in smokers in all conditions and reduced RT variability for simple number decisions and simultaneous distractors. Overall, there was a nonsignificant trend for smokers to be less accurate than nonsmokers. Accuracy in the simultaneous distractor condition decreased in both groups in phase 2. We argue that the observed nicotine-induced improvements on behavioral performance primarily reflect enhancement of top-down control of attention.
尼古丁对注意力的增强作用通常归因于注意力网络对刺激过滤的增强。我们调查了20名戒烟者（夜间9小时不吸烟；第一阶段）的注意力分散情况，并在他们吸了一支烟后再次进行测试（第二阶段）。将他们的表现与20名不吸烟者（未摄入尼古丁）进行比较。在一项听觉数字奇偶判断任务中，参与者必须对中央呈现的2到9之间的数字做出“奇数”或“偶数”的强制选择，同时忽略横向呈现的先前或同时出现的新干扰物。在第一阶段，目标刺激之前的干扰物比两组中同时呈现的干扰物更能减慢反应时间（RTs）。在第二阶段，尼古丁摄入使吸烟者在所有条件下的反应时间加快，并降低了简单数字决策和同时出现干扰物时的反应时间变异性。总体而言，吸烟者的准确性略低于不吸烟者，但差异不显著。在第二阶段，两组在同时出现干扰物的情况下准确性均下降。我们认为，观察到的尼古丁对行为表现的改善主要反映了自上而下注意力控制的增强。
