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bioRxiv · 10.1101/538439

Contextual cues as modifiers of cTBS effects on indulgent eating

Abstract

BackgroundPrior studies have found that continuous theta burst stimulation (cTBS) targeting the left dlPFC results in reliable increases in consumption of calorie-dense food items. However, it is not known to what extent such effects are modified by cues in the immediate eating environment. Tempting environments (i.e., those saturated with appetitive eating cues) may lead to more reliance on cognitive control networks involving the dlPFC, thereby enhancing cTBS on eating. Objective/HypothesisThe objective was to examine the extent to which cTBS effects on eating would be modified by contextual cues. It was hypothesized that cTBS effects on eating would be stronger in the presence of facilitating cues. MethodsUsing a between-subjects factorial design, 107 adults were randomly assigned to one of four conditions: 1) active cTBS + facilitating cues, 2) sham cTBS + facilitating cues, 3) active cTBS + inhibiting cues, 4) sham cTBS + inhibiting cues. Following stimulation participants completed a flanker paradigm and a taste test during which quantity consumed was assessed surreptitiously. ResultsFindings revealed a significant interaction between stimulation and cue type (F(1,102)=6.235, p=.014), such that the effects of cTBS were stronger for those in the facilitating cue condition. ConclusionsThe effects of cTBS on eating are strengthened in the presence of facilitating cues. Methodologically speaking, facilitating cues may be a functional prerequisite for exploring cTBS effects on eating in the laboratory. Substantively, the findings also suggest that facilitating cues in the eating environment may amplify counter-intentional food indulgence in everyday life via cognitive control failure.

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BibTeXRIS

Safati, A. B., Hall, P. A.. 2019-02-01. Contextual cues as modifiers of cTBS effects on indulgent eating. https://doi.org/10.1101/538439

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