Leland D S, Pineda J A
Department of Psychiatry, University of California, San Diego, La Jolla, CA 92037-0515, USA.
Clin Neurophysiol. 2006 Jan;117(1):67-84. doi: 10.1016/j.clinph.2005.09.004. Epub 2005 Dec 6.
Attention biases toward food-related stimuli were examined as mediators of normal, healthy motivated behavior.
Reaction times (RTs) and event-related potentials (ERPs) were used to assess the impact of food-related words on normal food-deprived individuals when used as spatial cues that frequently predicted the location of targets in a simple detection task (75% validity).
In Experiment 1, fasting and nonfasting subjects showed a magnified cost/benefit of invalid/valid cueing by food words relative to a neutral category of words. In Experiment 2, the RT effect was replicated in a group of fasting subjects. The amplitude of a P3-like positivity (P420) was enhanced in response to food words, as was that of a prominent early anterior negativity (AN).
These findings demonstrate that food-related stimuli can bias spatial attention in normal subjects and that electrophysiological markers can index the motivational salience of food words and/or their effect on attentional capture in food-deprived individuals.
Even when the motivational salience of spatial cues is irrelevant to task demands, it can have an observable effect on attention. This design allows for the behavioral and electrophysiological study of motivation-attention interactions through loading of spatial cues with motivation-related semantic properties.
研究对食物相关刺激的注意偏向作为正常、健康动机行为的中介。
当食物相关词汇用作空间线索时,使用反应时(RTs)和事件相关电位(ERPs)来评估其对正常饥饿个体的影响,这些线索在一个简单检测任务中频繁预测目标位置(有效性为75%)。
在实验1中,与中性词汇类别相比,禁食和非禁食受试者在无效/有效线索提示方面,食物词汇显示出更大的成本/收益。在实验2中,一组禁食受试者重复出现了反应时效应。对食物词汇的反应中,类似P3的正波(P420)以及一个显著的早期前部负波(AN)的波幅都增强了。
这些发现表明,食物相关刺激可使正常受试者的空间注意产生偏向,并且电生理标记可以指示食物词汇的动机显著性和/或其对饥饿个体注意捕获的影响。
即使空间线索的动机显著性与任务要求无关,它也可能对注意产生可观察到的影响。这种设计允许通过赋予空间线索与动机相关的语义属性来对动机-注意相互作用进行行为和电生理研究。