古典美还是表现美:摆盘美学影响健康饮食决策的计算与神经机制

Classical or expressive aesthetics: Computational and neural mechanismsby which plating aesthetics influence healthy eating decisions

前人研究发现食物摆盘的美感水平会影响个体的食物选择,但未有研究进一步探讨相同美感、不同审美特征对健康饮食决策的影响机制。本研究招募被试34名,采用基于价值的食物决策范式,使用2 (审美特征:古典美,表现美)×2 (食物热量:高,低)被试内设计,通过分离计算模型参数与脑电指标来检验不同审美特征差异化的审美价值,以及审美价值对热量影响的调节效应及其认知神经基础。结果显示:(1)古典美(vs.表现美)审美价值更高,食物选择率和漂移率(v)更高、N400振幅更低;(2)审美价值调节热量价值,但热量价值的突显性高于审美,热量信息的神经处理时间更早(240~320ms);(3)审美价值的调节效应发生在决策证据积累过程中,影响漂移率(v)以及中央顶叶正波(CPP)。本研究在理论层面揭示了健康饮食决策中审美价值的调节效应及认知神经基础,同时在实践应用方面为助推健康饮食选择提供了食物摆盘的审美设计指导。

The spontaneous human preference for high-calorie foods often leads to imbalanced dietary intake and contributes to obesity.Therefore,reducing the appeal of high-calorie foods and enhancing the appeal of low-calorie alternatives are crucial for promoting healthy eating.The aesthetics of food,which can be divided into classical and expressive beauty—both of which are perceived as equally attractive—play a vital role in enhancing its hedonic value.This study aimed to explore how these two aesthetic classifications affect the choice of high-or low-calorie foods using a food decision-making paradigm.By investigating the behavioural and neural mechanisms underlying the influence of different aesthetic features on healthy food choices,we sought to enhance our understanding of the intrinsic processes involved in dietary decision-making.This study(N=31)employed a within-subjects experimental design of 2(Aesthetic features:classical beauty,expressive beauty)×2(Food calories:high,low)to explore how visual aesthetics and hedonic value influence dietary decisions.We combined behavioural measures,algorithmic modelling,and electroencephalography(EEG)to investigate this interaction.Specifically,a hierarchical drift diffusion model(HDDM)was used to fit participants'response times(RTs)and choice data and estimate decision parameters,including drift rate(v),threshold(a),and nondecision time(ndt),for each condition separately.EEG recordings were collected according to the international 10-20 system using tin electrodes mounted on a flexible cap,capturing brain activity from 64 scalp locations.The N300,N400,and CPP event-related potentials(ERPs)were analysed as indices of calorie processing,aesthetic feature processing,and decision signal accumulation,respectively.Behavioural results revealed that participants preferred high-calorie foods,as indicated by higher choice rates and shorter RTs,compared to low-calorie foods.Additionally,foods plated with classical beauty were chosen more frequently and with shorter RTs than those plated with expressive beauty.Notably,the influence of caloric content on food choice was significantly greater than that of aesthetic features.HDDM parameter estimation showed that high-calorie foods and those plated with classical beauty had higher drift rates,suggesting faster decision-making.Furthermore,aesthetic features moderated the impact of caloric content on drift rates:classical beauty decreased rejection speeds for low-calorie foods and increased their selection probability,while expressive beauty slowed the choice process for high-calorie foods and increased their rejection probability.EEG analysis revealed that low-calorie foods elicited a larger N300 amplitude than did high-calorie foods,indicating greater cognitive processing.Foods plated with expressive beauty elicited a larger N400 amplitude than those plated with classical beauty, indicating deeper semantic processing. Additionally, forhigh-calorie foods, the two aesthetic classes induced significant differences in CPP;however, for low-caloriefoods, no significant differences were found. This pattern indicates that conflicts between caloric and aestheticvalues increase decision-making difficulty.In conclusion, the results showed that in dietary decision-making, classical beauty (vs. expressive beauty)was associated with greater aesthetic value and greater semantic processing fluency. Aesthetic value couldsignificantly influence the perceived reward of calorie content. Additionally, the salience of calorie valueexceeded that of aesthetic value. Furthermore, both synergistic and competitive interactions between caloric andaesthetic values occurred during the decision evidence accumulation process, reflecting the intensity ofmotivational conflict and affecting both decision speed (v) and decision difficulty (CPP). This study revealed themoderating effect and cognitive neural basis of aesthetic value in healthy eating decisions and providedguidance on the aesthetic design of food plating for promoting healthy eating choices in practical applications.