How do our brains resist cues linked to food?

Explore how our research is investigating environmental suppression of food seeking and activity in mice.

Our research

Overeating and obesity are major global health concerns with an associated impact on public health due to diseases associated with it such as diabetes and cardiac problems.

Our research focuses on cues linked to food which can have powerful effects making us crave foods and driving us to overeat which may contribute to obesity. We know a lot about how we learn about these cues, but we know less about the ways in which we can resist food cues. What are the inbuilt mechanisms in our brains that allow us to resist these cues?

Previous research has shown that short periods of physical exercise or mental stimulation (such as going for walks or playing a video game) can reduce craving and eating in humans. Our study has used a mouse model of this which uses environmental enrichment – where mice are placed in a large colourful cage with access to toys, running wheels and tunnels.

We investigated the impact of environmental enrichment on food seeking and on activity in the mouse prefrontal cortex – a brain region we know if important in responding to food cues. We found that brief exposure to an enriching environment with cognitive and physical stimulation reduced cue evoked food seeking in mice. When mice hear a cue, they have been trained to associate with sweet rewards this has less of an effect on enriched mice's' 'craving'.

We then explored how the prefrontal cortex is involved in this resilience to food cues using slice electrophysiology, FosTRAP tagging and fibre photometry experiments. These methods allowed us to record neuronal activity in awake behaving mice and track which types of cells are activated by food related cues.

We found a combination of excitatory overdrive within pyramidal cells of the prefrontal cortex, and we saw a complementary underdrive in inhibitory interneurons. This paper identifies key mechanisms by which environmental enrichment conveys a resilience to food seeking which could lead to potential neurophysiological targets to control food craving.

Benefits of the research

Our results can be used by pharmaceutical companies to be able to design more efficacious therapeutics that stimulate or inhibit specific neuronal populations that encode appetitive memories and motivation. Using such treatments, we may stimulate appetite in those suffering from disorders such as cancer or decrease appetite for those suffering from overeating. Our research also has implications for other conditions such as age-related memory decline and addiction which increases the number of beneficiaries for potential novel treatments.