Mattavelli Giulia, Zuglian Pablo, Dabroi Elisa, Gaslini Guia, Clerici Massimo, Papagno Costanza
Department of Psychology, University of Milano-Bicocca, P.za Ateneo Nuovo 1, 20126 Milano, Italy.
Department of Surgery and Translational Medicine, University of Milano-Bicocca, San Gerardo Hospital, Via Pergolesi, 33, Monza, Italy.
Appetite. 2015 Jun;89:70-6. doi: 10.1016/j.appet.2015.01.014. Epub 2015 Jan 22.
The medial prefrontal cortex (mPFC) is known to be associated with food representation and monitoring of eating behaviour, but the neural mechanisms underlying attitudes towards food are still unclear. Transcranial magnetic stimulation (TMS) was used in combination with the implicit association test (IAT) to investigate the causal role of mPFC in controlling implicit food evaluation in healthy volunteers. Participants performed an IAT on tasty and tasteless food to test TMS interaction with food evaluation. Moreover, IATs assessing self-related concepts and attitude towards flowers and insects were carried out to control whether TMS could also affect self-representation or, more in general, the cognitive mechanisms required by the IAT. TMS was applied over mPFC; the left parietal cortex (lPA) was also stimulated as control site. Results revealed that mPFC-TMS selectively affected IAT on food, increasing implicit preference for tasty than tasteless food, only in a subgroup of participants who did not show extreme explicit evaluation for tasty and tasteless food. This demonstrates that mPFC has a critical causal role in monitoring food preference and highlights the relevance of considering individual differences in studying food representation and neural mechanisms associated with eating behaviour.
内侧前额叶皮质（mPFC）已知与食物表征及进食行为监测有关，但对食物态度背后的神经机制仍不清楚。经颅磁刺激（TMS）与内隐联想测验（IAT）相结合，用于研究mPFC在健康志愿者控制内隐食物评价中的因果作用。参与者对美味和无味食物进行IAT，以测试TMS与食物评价的相互作用。此外，还进行了评估自我相关概念以及对花和昆虫态度的IAT，以控制TMS是否也会影响自我表征，或者更一般地说，是否会影响IAT所需的认知机制。TMS作用于mPFC；左侧顶叶皮质（lPA）也作为对照部位受到刺激。结果显示，mPFC-TMS仅在对美味和无味食物没有表现出极端明确评价的参与者亚组中，选择性地影响了对食物的IAT，增加了对美味食物而非无味食物的内隐偏好。这表明mPFC在监测食物偏好方面具有关键的因果作用，并突出了在研究食物表征及与进食行为相关的神经机制时考虑个体差异的重要性。
