Barcode activity in a recurrent network model of the hippocampus enables efficient memory binding

• DOI: 10.7554/elife.103512.1
• Publication Date: 2025-01-09T17:25:31Z
• Authors: Ching Fang; Jack Lindsey; Larry F Abbott; Dmitriy Aronov; Selmaan Chettih
• Keywords: Barcode

Forming an episodic memory requires binding together disparate elements that co-occur in a single experience. One model of this process is neurons representing different components bind to “index” — subset unique memory. Evidence for has recently been found chickadees, which use hippocampal store and recall locations cached food. Chickadee hippocampus produces sparse, high-dimensional patterns (“barcodes”) uniquely specify each caching event. Unexpectedly, the same participate barcodes also exhibit conventional place tuning. It unknown how barcode activity generated, what role it plays formation retrieval. unclear index (e.g. barcodes) could function neural population represents content place). Here, we design biologically plausible generates uses them experiential content. Our from inputs through chaotic dynamics recurrent network Hebbian plasticity as attractor states. The matches experimental observations indices (barcodes) signals (place tuning) are randomly intermixed neurons. We demonstrate reduce interference between correlated experiences. show tuning complementary barcodes, enabling flexible, contextually-appropriate Finally, our compatible with previous models generating predictive map. Distinct indexing functions achieved via adjustment global gain. results suggest may resolve fundamental tensions specificity (pattern separation) flexible completion) general systems.