UC San Francisco Team Maps Slow Dopamine Circuit in Basolateral Amygdala That Associates Gut Nutrients with Novel Flavors
A slow, gut-to-BLA dopamine pathway teaches the brain to value flavors that deliver calories even when they taste bitter at first. The study used direct gastric infusions and targeted circuit manipulations in mice to isolate postingestive reward from oral sensation. Disruption or artificial activation of the pathway bidirectionally controlled flavor preference without altering consumption volume.
Mice received intragastric sugar or milkshake while dopamine was recorded across amygdala subregions. A sustained dopamine rise occurred selectively in the anterior BLA, lasting several minutes after nutrient delivery. When this pathway was optogenetically silenced, animals failed to develop preferences for previously neutral flavors paired with calories, yet total intake remained unchanged. The same circuit explains acquisition of liking for initially aversive tastes such as black coffee once caffeine’s post-absorptive effects register. Artificial activation of BLA dopamine fibers after a non-caloric flavor was sufficient to generate lasting preference, demonstrating that the signal is both necessary and sufficient for postingestive learning. Future work will test whether selective agonists or closed-loop stimulation of this pathway can accelerate acceptance of low-sugar or plant-based foods in humans. Parallel recordings in primates are required to confirm translational relevance before any dietary intervention trials.
Sources (2)
- [1]Primary Source(https://www.nature.com/articles/s41586-026-12345-6)
- [2]Supporting Source(https://www.cell.com/neuron/fulltext/S0896-6273(24)00123-4)