Infinite storage in quasi-memory: a cryptographic principle underlining caching behavior in animals

The brain's extraordinary abilities are often associated with its ability to learn and adapt. But memory and plasticity, in general, have their limitations, especially when faced with the tasks such as retrieving hundreds of thousands of items, such as in the case of scatter-hoarding animals. Here, we present a brain mechanism that works by utilizing cryptographic principles in lieu of plasticity. Rather than memorizing the locations of their caches, as previously suggested, we propose that cache-hoarding animals use a single cryptographic-like mechanism for both caching and retrieval. The model we developed functions similarly to hippocampal spatial cells, which respond to an animal’s positional attention. We know that the region that activates each spatial cell remains consistent across subsequent visits to the same area but not between areas. This remapping, combined with the uniqueness of cognitive maps, produces a persistent crypto-hash function for both food caching and retrieval. We show that our model is consistent with previous observations, such as animals’ ability to prioritize food items that are perishable or by their nutritional value. While focusing here on scatter-hoarding, the mechanism we present might be utilized by the brain in other ways providing essentially infinite retention capacity for structured data.