Nicotine: Cognition-Affect Interactions

描述(由申请人提供)：这项修订提案的主要目标是更全面地描述尼古丁何时、如何以及在谁体内调节对情绪刺激的影响和注意力。假设尼古丁减弱了对负面情绪刺激的注意偏向和对这些刺激的联合加工，从而减少了负面情绪状态。尼古丁对负性注意偏向和联想加工的减弱被认为是由于尼古丁增强了对积极和中性刺激的注意偏向和联想偏向，而这反过来又竞争和抑制了负性情感相关的加工。尼古丁诱导的注意偏向和联想偏向被认为是在负面刺激频率中等或低的情况下发生的最强烈的，并且受试者有很大程度的注意选择自由。因此，通过在计算机上呈现一系列的单张或双张图片，来评估注意选择(两张图片观看)和无选择(一张图片观看)条件对尼古丁减少负面情绪能力的影响。情绪将在每个系列图片块之前和之后进行评估。这些系列中负片的频率将被操纵(16[低频]或48[高频])。在非选择任务中，单张图片将集中呈现在计算机屏幕上。在二选一任务中，左右视野中将同时呈现双画面图像。图片系列块(单张或双张图片)将由以下4.5秒组成。顺序：单词“眨眼”、一个固定十字和一张图片(或双图片)。在二选一的情况下，受试者会被指示将相同或更少的凝视时间分配给给定的图片，但始终盯着两张图片中的一张。在没有选择的情况下，受试者将被要求保持3秒的时间。凝视每一张图片。在两项选择和非选择任务中都会穿插中性或积极的图片。在双选项和非选项任务中，眼睛的凝视模式将通过红外线计算机跟踪系统获得。在两项选择任务中，尼古丁的焦躁不安最大缓解效果预计出现在出现高频率负面图片的区块中。尼古丁预计会减少对负面图片的凝视，提高对正面图片的注意力。在没有选择的任务中，当低频率的负面图片与中间的正面图片相结合时，尼古丁有望具有最大的焦虑不安效果。将通过回归分析评估性别、吸烟者-非吸烟者状态以及特质焦虑、抑郁和快感缺失方面的个体差异的潜在缓和影响。这项工作将使用新的实验程序和技术，包括通过红外计算机跟踪系统对连续监测的眼睛凝视模式中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以经验模型为基础的治疗策略，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.