Transcranial magnetic stimulation of medial prefrontal cortex modulates implicit attitudes towards food

• Published in: Appetite 2015-06, Vol.89, p.70-76
• Main Authors: Mattavelli, Giulia, Zuglian, Pablo, Dabroi, Elisa, Gaslini, Guia, Clerici, Massimo, Papagno, Costanza
• Format: Article
• Language: English
• Subjects: Attitude; Brain Mapping; Cognition; Diet; Feeding Behavior - physiology; Feeding Behavior - psychology; Food evaluation; Food Preferences - physiology; Food Preferences - psychology; Healthy Volunteers; Humans; IAT; Individuality; Inhibition; Medial prefrontal cortex; Prefrontal Cortex - physiology; Taste; TMS; Transcranial Magnetic Stimulation - methods
• ISSN: 0195-6663; 1095-8304
• DOI: 10.1016/j.appet.2015.01.014

•mPFC seems to be associated with food representation.•Implicit association test (IAT) can measure implicit food preference.•TMS applied over mPFC during IAT increased implicit preference for tasty foods.•Individual differences in explicit food preference modulated the effect of mPFC-TMS.•mPFC is causally involved in food evaluation. 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.