Emergent neural dynamics and geometry for generalization in a transitive inference task

• Published in: PLoS computational biology Vol. 20; no. 4; p. e1011954
• Main Authors: Kay, Kenneth, Biderman, Natalie, Khajeh, Ramin, Beiran, Manuel, Cueva, Christopher J, Shohamy, Daphna, Jensen, Greg, Wei, Xue-Xin, Ferrera, Vincent P, Abbott, L F
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.04.2024; Public Library of Science (PLoS)
• Subjects: Analysis; Animal cognition; Behavior; Brain; Cognition; Cognitive ability; Human performance; Hypotheses; Inference; Linguistics; Memory; Mental task performance; Neural networks; Neurosciences; United States
• ISSN: 1553-7358; 1553-734X; 1553-7358
• DOI: 10.1371/journal.pcbi.1011954

Relational cognition-the ability to infer relationships that generalize to novel combinations of objects-is fundamental to human and animal intelligence. Despite this importance, it remains unclear how relational cognition is implemented in the brain due in part to a lack of hypotheses and predictions at the levels of collective neural activity and behavior. Here we discovered, analyzed, and experimentally tested neural networks (NNs) that perform transitive inference (TI), a classic relational task (if A > B and B > C, then A > C). We found NNs that (i) generalized perfectly, despite lacking overt transitive structure prior to training, (ii) generalized when the task required working memory (WM), a capacity thought to be essential to inference in the brain, (iii) emergently expressed behaviors long observed in living subjects, in addition to a novel order-dependent behavior, and (iv) expressed different task solutions yielding alternative behavioral and neural predictions. Further, in a large-scale experiment, we found that human subjects performing WM-based TI showed behavior inconsistent with a class of NNs that characteristically expressed an intuitive task solution. These findings provide neural insights into a classical relational ability, with wider implications for how the brain realizes relational cognition.