Nicotine: Cognition-Affect Interactions

描述（由申请人提供）：本修订提案的主要目的是更全面地描述尼古丁何时、如何以及在谁身上调节对情绪刺激的影响和注意。假设尼古丁减弱了对消极情绪刺激的注意偏倚和对这种刺激的联想加工，从而减少了消极情绪状态。尼古丁对负性注意偏差和联想加工的衰减被认为是由于尼古丁增强了对正性和中性刺激的注意和联想偏见，而这反过来又与负性情感相关加工竞争并抑制了它们。假设尼古丁引起的注意和联想偏倚在负面刺激频率适中或较低的情况下发生得最强烈，并且受试者有很大程度的注意选择自由。因此，注意力选择（两张图片观看）和不选择（一张图片观看）条件对尼古丁减少负面影响的影响将通过在电脑上展示一系列64张单张或双张图片来评估。在每个图片系列块之前和之后将评估情绪。这些系列中的负图片的频率将被操纵（16[低频]或48[高频]）。在无选择任务中，单个图片将集中显示在计算机屏幕上。在双选择任务中，双图像将在左右视野中同时呈现。图片系列块（64张单张或双张图片）将由以下4.5秒的序列组成：“眨眼”字、注视十字、图片（或双张图片）。在两种选择条件下，受试者将被指示分配尽可能多或少的凝视时间给给定的图片，但总是盯着两张图片中的一张。在无选择条件下，受试者将被要求对每张图片保持3秒的凝视。中性或积极的图片会穿插在两种选择和无选择的任务中。在两项选择任务和无选择任务期间，眼睛的注视模式将通过红外计算机跟踪系统获得。在两项选择任务中，尼古丁减少烦躁不安的最大效果预计发生在负面图片频率高的时段。据预测，尼古丁会减少人们对消极图片的注视，增强人们对积极图片的关注。在无选择任务中，当低频率的消极图像与干预的积极图像相结合时，尼古丁预计会有最大的减少烦躁不安的效果。性别、吸烟-不吸烟状态以及特质焦虑、抑郁和快感缺乏的个体差异的潜在调节影响将通过回归分析进行评估。这项工作将使用新的实验程序和技术，包括用红外计算机跟踪系统对连续监测的眼睛注视模式的个体差异进行精确评估。从这些研究中获得的新知识将有助于开发基于经验模型的治疗策略，旨在增加戒烟。

DESCRIPTION (provided by applicant): The primary objective of this revised proposal is to characterize more fully when, how, and in whom nicotine modulates affect and attention to emotional stimuli. It is hypothesized that nicotine attenuates attentional bias to negative emotional stimuli and associative processing of such stimuli, thereby decreasing negative emotional states. This attenuation of negative attentional bias and associative processing by nicotine is hypothesized to result from nicotine's enhancing attentional and associative bias to positive and neutral stimuli that in turn compete with and inhibit negative affect-related processing. Nicotine-induced attentional and associative biasing is hypothesized to occur most strongly in situations where the frequency of negative stimuli is moderate or low and the subject has a significant degree of freedom of attentional choice. Thus, the effects of attentional choice (two-picture viewing) versus no-choice (one picture viewing) conditions on nicotine's ability to reduce negative affect will be assessed by presenting blocks with a series of 64 single or dual pictures on a computer. Mood will be assessed before and after each picture series block. The frequency of negative pictures in these series will be manipulated (either 16 [low frequency] or 48 [high frequency]). In the no-choice task, single pictures will be presented centrally on the computer screen. In the two-choice task, dual picture images will be presented simultaneously in the left and right visual field. Picture series blocks (64 single or dual pictures) will consist of the following 4.5 sec. sequence: the word "blink", a fixation cross, and a picture (or dual picture). In the two-choice condition, subjects will be instructed to allocate as much or little of their gaze time to a given picture, but to always be gazing at one of two pictures. In the no-choice condition, subjects will be required to maintain a 3 sec. gaze at each picture. Neutral or positive pictures will be interspersed in both the two-choice and no-choice tasks. Eye-gaze patterns during the two-choice task and no-choice task will be obtained with an infrared, computerized tracking system. In the two-choice task, maximal dysphoria-reducing effects of nicotine are predicted to occur during blocks with a high frequency of negative pictures. Nicotine is predicted to reduce gaze directed toward negative pictures and to enhance attention to positive pictures. In the no-choice task, nicotine is expected to have maximal dysphoria-reducing effects when a low frequency of negative pictures is combined with intervening positive pictures. Potential moderating influences of gender, smoker-nonsmoker status, and individual differences in trait anxiety, depression, and anhedonia will be assessed with regression analyses. This work will use new experimental procedures and technologies, including the precise assessment to individual differences in continuously monitored eye-gaze patterns with an infrared, computerized tracking system. The new knowledge derived from these studies will be useful in developing empirical model-based treatment strategies aimed at increasing smoking abstinence.