Department of Biomedical Sciences, Bioagromed, University of Foggia, Italy.
Int J Psychophysiol. 2011 Nov;82(2):153-66. doi: 10.1016/j.ijpsycho.2011.08.001. Epub 2011 Aug 18.
Here we tested the hypothesis that compared with normal weight non dieting (control) subjects, normal weight successful dieters submitted to a rigorous and continuous monitoring of body weight (i.e. karate athletes) are characterized by an increase of cortical responses to oddball visual stimuli depicting the enlargement of faces or foods, as neural underpinning of attention processes related to the control of weight and eating. Electroencephalographic (EEG) data were recorded in 18 successful dieters (5 females) and 24 non dieting subjects (9 females). The subjects were given frequent (70%) and rare (30%) stimuli depicting faces (FACE), food (FOOD), and landscapes (CONTROL). The task was to click the mouse after the rare stimuli. The rare stimuli depicted the frequent stimuli graphically dilated by 25% along the horizontal axis. Cortical responses accompanying attention processes were probed by the difference between positive event-related potentials peaking around 400-500ms post-stimulus for the rare minus frequent stimuli (P300). The popular freeware LORETA estimated P300 cortical sources. The results showed that in the FACE condition, the amplitude of left frontal (BA 6) and medial parietal (BA 5) P300 sources was higher in the successful dieters (karate athletes) than non dieting subjects. These results disclose that frontal-parietal responses to "oddball" stimuli depicting enlarged faces (i.e. representing face fattening) are enhanced in successful dieters (karate athletes). Future studies should evaluate this effect in other populations of successful dieters (i.e. boxers, top models etc.).
在这里，我们检验了一个假设，即与正常体重非节食者（对照组）相比，正常体重成功节食者在严格持续的体重监测下（即空手道运动员），对面部或食物放大的奇怪视觉刺激的皮质反应增加，这是与体重和饮食控制相关的注意过程的神经基础。在 18 名成功节食者（5 名女性）和 24 名非节食者（9 名女性）中记录了脑电图（EEG）数据。给予受试者频繁（70%）和罕见（30%）的面部（FACE）、食物（FOOD）和景观（CONTROL）刺激。任务是在罕见刺激后点击鼠标。罕见刺激是通过将频繁刺激沿水平轴图形放大 25%来描绘的。通过罕见刺激减去频繁刺激的正事件相关电位（P300）之间的差异来探测伴随注意过程的皮质反应。流行的免费 LORETA 估计了 P300 皮质源。结果表明，在 FACE 条件下，成功节食者（空手道运动员）左额叶（BA6）和内侧顶叶（BA5）P300 源的振幅高于非节食者。这些结果表明，成功节食者（空手道运动员）对“奇怪”刺激的额顶反应增加，这些刺激描绘了放大的面部（即代表面部肥胖）。未来的研究应该在其他成功节食者（如拳击手、顶级模特等）群体中评估这种效果。
