New research from Kent reveals that images of food hold our attention for longer than images unrelated to food, especially when the food is high in calories.
This heightened response to high-calorie foods could significantly contribute to overeating, suggesting that interventions which reduce the amount and diversity of food in the environment could promote weight-control.
Habituation, or the brain’s diminishing response to a stimulus -such as ‘forbidden’ unhealthy food- over time, is often put forward as a case for eating whatever one wants as the expectation is that the more the brain is exposed to something, it will desire it less over time.
Researchers in the School of Computing set out to understand whether this habituation response differs between those with a high or low Body Mass Index (BMI). Using a technique known as electroencephalography (EEG), the team monitored the brain signals of participants when repeatedly shown images of high-calorie, low-calorie and non-food. They then used event-related potential (ERP) analysis to measure neural responses to different stimuli across BMI groups and employed statistical tests to assess significant differences and habituation dynamics.
They found that in both BMI groups, signals of attention and motivation in the brain decreased over time when participants were repeatedly shown non-food images. In contrast, brain signals remained high when participants were repeatedly shown images of apples and pizza, with the latter eliciting more brain activity for longer.
Dr Palaniappan Ramaswamy said: ‘Our findings suggest that an individual’s brain shows more attention towards food images for a longer time irrespective of whether they are overweight or not. For those in the high BMI group, this could mean they are more likely to keep on gaining weight, whilst those in the low BMI group are at risk of becoming overweight/obese in the future.
Research student, Aruna Duraisingam , added: ‘This indicates that interventions focusing on swapping the variety of high-calorie foods for healthful low-calorie foods could encourage people to eat more of the latter, which in turn would increase their satiety and reduce their calorie consumption. Reducing cues for high-calorie items in our environment would minimise the need for repeated acts of self-control when choosing healthier options and could offer straightforward environmental strategies for weight control.’
Aruna Duraisingam, Dr Daniel Soria and Dr Palaniappan Ramaswamy presented their findings at the 5th International Conference on Data Intelligence and Cognitive Informatics in Tirunelveli, India on 18 November.
In the video below, Aruna explains their research on food habituation as part of the 3 Minute Thesis competition.