Geometry of sequence working memory in macaque prefrontal cortex.

Publisher: American Association for the Advancement of Science Country of Publication: United States NLM ID: 0404511 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1095-9203 (Electronic) Linking ISSN: 00368075 NLM ISO Abbreviation: Science Subsets: MEDLINE

Publication: : Washington, DC : American Association for the Advancement of Science
Original Publication: New York, N.Y. : [s.n.] 1880-

Memory, Short-Term*; Neurons/*physiology ; Prefrontal Cortex/*cytology ; Prefrontal Cortex/*physiology; Animals ; Calcium/metabolism ; Macaca mulatta ; Models, Neurological ; Spatial Memory

How the brain stores a sequence in memory remains largely unknown. We investigated the neural code underlying sequence working memory using two-photon calcium imaging to record thousands of neurons in the prefrontal cortex of macaque monkeys memorizing and then reproducing a sequence of locations after a delay. We discovered a regular geometrical organization: The high-dimensional neural state space during the delay could be decomposed into a sum of low-dimensional subspaces, each storing the spatial location at a given ordinal rank, which could be generalized to novel sequences and explain monkey behavior. The rank subspaces were distributed across large overlapping neural groups, and the integration of ordinal and spatial information occurred at the collective level rather than within single neurons. Thus, a simple representational geometry underlies sequence working memory.

SY7Q814VUP (Calcium)

Date Created: 20220210 Date Completed: 20220218 Latest Revision: 20220218

20231215

10.1126/science.abm0204

35143322