A new study, by Macquarie University, has revealed that memory inhibition is linked to dietary excess caused by the Western style diet. Food memory blocks out memories linked to dietary excess and depends on a brain area called the hippocampus. Thoughts of food are set aside when people are full and eating is no longer a priority.
The Western style diet on the other hand impairs the memory inhibition abilities of the hippocampus. Research reported at the annual meeting of the Society for the Study of Ingestive Behavior, (SSIB), reported that memory food performance and snack food ratings were linked.
Participants completed learning and memory tests that depend on the hippocampus and also rated their liking and wanting of palatable snack foods before and after a filling lunch. Participants who habitually ate a Western-style diet were slower at learning and had had problems remembering compares to those who ate a healthier diet.
“Even though they were full, they still wanted to eat the sweet and fatty junk food”, said Tuki Attuquayefio, the research author. “What was even more interesting was that this effect was strongly related to their performance on the learning and memory task, suggesting that there is a link between the two via the hippocampus.”
The study confirms prior animal research and suggests that people with greater intake of a high fat, high sugar diet may perform poorly on the learning and memory tests because of how the diet impacts the hippocampus. The inability to inhibit food memories when in a satiated physiological state could then explain the persistent desire for snacks. Healthy, lean, young people who routinely consume high-fat high-sugar diets may have a compromised hippocampal function making it harder to regulate food intake. This will set them upon the road towards obesity.
Research: Western diet intake predicts hippocampal learning and state-dependent inhibition of wanting for snack foods: Evidence from human subjects..
Lead Author: Tuki Attuquayefio, PhD Candidate, Department of Psychology, Macquarie University
1. R. J. Stevenson, Department of Psychology, Macquarie University
2. R. Boakes, School of Psychology, University of Sydney
3. M. Oaten, School of Applied Psychology, Griffith University
4. M. R. Yeomans, School of Psychology, University of Sussex
5. M. Mahmut, Department of Psychology, Macquarie University
6. H. Francis, Department of Psychology, Macquarie University