Human spatial memory is biased towards high-calorie foods: a cross-cultural online experiment

Rachelle De Vries,Emely De Vet,Sanne Boesveldt

doi:10.1186/s12966-022-01252-w

Abstract

BackgroundHuman memory appears to prioritise locations of high-calorie foods, likely as an adaptation for foraging within fluctuating ancestral food environments. Importantly, this “high-calorie bias” in human spatial memory seems to yield consequences for individual eating behaviour in modern food-abundant settings. However, as studies have mainly been conducted in European (Dutch) populations to date, we investigated whether the existence of the cognitive bias can be reasonably generalised across countries that vary on culturally-relevant domains, such as that of the USA and Japan. Furthermore, we investigated whether sociodemographic factors moderate the expression of the high-calorie spatial memory bias in different populations.MethodsIn a cross-cultural online experiment, we measured the food location memory of diverse participants from the USA (N = 72; 44.4% Male; 54 ± 15.99 years) and Japan (N = 74; 56.8% Male; 50.85 ± 17.32 years), using a validated computer-based spatial memory task with standardised images of high-calorie and low-calorie foods. To directly compare the magnitude of the high-calorie spatial memory bias in a broader cultural scope, we also included data from a previous online experiment that identically tested the food spatial memory of a Dutch sample (N = 405; 56.7% Male; 47.57 ± 17.48 years).ResultsIn the US sample, individuals more accurately recalled (i.e. had lower pointing errors for) locations of high-calorie foods versus that of low-calorie alternatives (Mean difference = -99.23 pixels, 95% CI = [-197.19, -1.28]) – regardless of one’s hedonic preferences, familiarity with foods, and encoding times. Likewise, individuals in the Japanese sample displayed an enhanced memory for locations of high-calorie (savoury-tasting) foods (Mean difference = -40.41 pixels, 95% CI = [-76.14, -4.68]), while controlling for the same set of potential confounders. The magnitude of the high-calorie bias in spatial memory was similar across populations (i.e. the USA, Japan, and the Netherlands), as well as across diverse sociodemographic groups within a population.ConclusionsOur results demonstrate that the high-calorie bias in spatial memory transcends sociocultural boundaries. Since the cognitive bias may negatively impact on our dietary decisions, it would be wise to invest in strategies that intervene on our seemingly universal ability to efficiently locate calorie-rich foods.

Highlights

All organisms require energy from food to survive and reproduce [1]
The high‐calorie bias in spatial memory was demonstrated across sociodemographic groups in the US sample Individuals in the US sample exhibited an average food spatial memory accuracy of 316.64 pixels (SD = 209.10; Interdecile Range = 14.40 – 589.47)
A food’s caloric content was found to exert a medium sized influence, as it accounted for 6% of the variation in food spatial memory data, after partialling out effects of other predictors,ηp2 = 0.06, 90%CI ηp2 = [0.0004, 0.16]

Summary

Introduction

All organisms require energy from food to survive and reproduce [1]. Many nutritional ecology models predicting individuals’ eating behaviour make the de Vries et al Int J Behav Nutr Phys Act (2022) 19:14 fundamental assumption that natural selection favoured “optimal” foraging strategies that maximize the rate of energy gain [1,2,3]. Outcomes of earlier investigations indicate that this implicit “high-calorie bias” in human spatial memory may yield consequences for how individuals navigate modern food-abundant environments: An increased expression of the cognitive bias (i.e. a further improved memory for locations of high-calorie versus low-calorie foods) was found to predict a greater reported ease of finding high-calorie foods in a supermarket, more routine visits to high-calorie food retail locations (e.g. fastfood outlets), a stronger habit of purchasing high-calorie snack foods and a subsequently higher (less healthy) BMI [16,17,18]. Human memory appears to prioritise locations of high-calorie foods, likely as an adaptation for foraging within fluctuating ancestral food environments. This “high-calorie bias” in human spatial memory seems to yield consequences for individual eating behaviour in modern food-abundant settings. We investigated whether sociodemographic factors moderate the expression of the high-calorie spatial memory bias in different populations

Methods

Results

Discussion

Conclusion