Memory and Mealtime: Study Links Forgetfulness to Overeating

New Delhi: In a study published in Nature Communications, scientists from the University of Southern California (USC) have identified a specific group of brain cells that may explain why people with memory problems are more prone to overeating. The research reveals that certain neurons in the brain’s ventral hippocampus are responsible for forming "meal engrams"—specialized memory traces that store detailed information about eating events.

The study sheds light on the connection between memory and hunger, suggesting that remembering what and when we eat may play a key role in regulating appetite. The findings may help explain why individuals with memory impairments, such as those with Alzheimer’s disease, often struggle with disordered eating behaviors.

To uncover these findings, researchers used advanced neuroscience tools to observe brain activity in laboratory rats in real time as they consumed food. They found that meal-related memory neurons activated during eating and were distinct from neurons involved in other types of memory, such as spatial navigation. When these specific neurons were selectively destroyed, rats lost the ability to remember food locations but could still perform other memory tasks. This suggests the brain may have a dedicated system for processing meal-related memories.

The team also identified a critical connection between the ventral hippocampus and the lateral hypothalamus, the brain region responsible for regulating hunger. When this neural pathway was disrupted, rats not only failed to remember their last meal but also began overeating, highlighting the importance of memory in appetite control.

“Our work shows that memory isn’t just about the past—it plays a crucial role in shaping eating behavior and regulating hunger,” said Professor Scott Kanoski, senior author of the study.

Reference: Léa Décarie-Spain, Cindy Gu, Logan Tierno Lauer, Keshav S. Subramanian, Samar N. Chehimi, Alicia E. Kao, Serena X. Gao, Iris Deng, Alexander G. Bashaw, Molly E. Klug, Jessica J. Rea, Alice I. Waldow, Ashyah Hewage Galbokke, Olivia Moody, Kristen N. Donohue, Mingxin Yang, Guillaume de Lartigue, Kevin P. Myers, Richard C. Crist, Benjamin C. Reiner, Matthew R. Hayes, Scott E. Kanoski. Ventral hippocampus neurons encode meal-related memory. Nature Communications, 2025; 16 (1) DOI: 10.1038/s41467-025-59687-1