Department of Psychology, University of Salzburg, Salzburg, Austria; Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.
Behavioural Science Institute, Radboud University Nijmegen, The Netherlands.
Appetite. 2018 Jun 1;125:42-47. doi: 10.1016/j.appet.2018.01.032. Epub 2018 Jan 31.
Strong implicit responses to food have evolved to avoid energy depletion but contribute to overeating in today's affluent environments. The Approach-Avoidance Task (AAT) supposedly assesses implicit biases in response to food stimuli: Participants push pictures on a monitor "away" or pull them "near" with a joystick that controls a corresponding image zoom. One version of the task couples movement direction with image content-independent features, for example, pulling blue-framed images and pushing green-framed images regardless of content ('irrelevant feature version'). However, participants might selectively attend to this feature and ignore image content and, thus, such a task setup might underestimate existing biases. The present study tested this attention account by comparing two irrelevant feature versions of the task with either a more peripheral (image frame color: green vs. blue) or central (small circle vs. cross overlaid over the image content) image feature as response instruction to a 'relevant feature version', in which participants responded to the image content, thus making it impossible to ignore that content. Images of chocolate-containing foods and of objects were used, and several trait and state measures were acquired to validate the obtained biases. Results revealed a robust approach bias towards food only in the relevant feature condition. Interestingly, a positive correlation with state chocolate craving during the task was found when all three conditions were combined, indicative of criterion validity of all three versions. However, no correlations were found with trait chocolate craving. Results provide a strong case for the relevant feature version of the AAT for bias measurement. They also point to several methodological avenues for future research around selective attention in the irrelevant versions and task validity regarding trait vs. state variables.
强烈的食物内隐反应是为了避免能量枯竭而进化的，但在当今富裕的环境中，却导致了暴饮暴食。回避任务（AAT）据称评估了对食物刺激的内隐偏见：参与者用操纵杆推动监视器上的图片“远离”或“拉近”，操纵杆控制相应的图像缩放。任务的一个版本将运动方向与与图像内容无关的特征（例如，拉动蓝色框架的图像和推动绿色框架的图像，而不考虑内容）结合起来，无论内容如何。然而，参与者可能会选择性地关注这个特征，而忽略图像内容，因此，这样的任务设置可能会低估现有的偏见。本研究通过将任务的两个无关特征版本与更外围的（图像框架颜色：绿色与蓝色）或中央的（小圆圈与图像内容上的十字叠加）图像特征进行比较，来测试这种注意解释，作为对“相关特征版本”的反应指令，参与者对图像内容做出反应，从而不可能忽略该内容。研究使用了含有巧克力的食物和物体的图片，并获得了几个特质和状态的测量值来验证所获得的偏见。结果表明，只有在相关特征条件下，才会对食物产生强烈的接近倾向。有趣的是，当结合所有三种条件时，在任务期间发现了与状态巧克力渴望的正相关，表明了所有三种版本的标准有效性。然而，与特质巧克力渴望没有相关性。结果强烈支持 AAT 的相关特征版本用于偏见测量。它们还指出了未来研究中围绕无关版本的选择性注意以及特质与状态变量的任务有效性的几个方法途径。
