Cross-Situational Learning Is Supported by Propose-but-Verify Hypothesis Testing

• Published in: Current biology Vol. 28; no. 7; pp. 1132 - 1136.e5
• Main Authors: Berens, Sam C., Horst, Jessica S., Bird, Chris M.
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 02.04.2018
• Subjects: Adult; Algorithms; Association Learning - physiology; computational modeling; cross-situational learning; Female; fMRI; hippocampus; Hippocampus - physiology; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Memory - physiology; Pattern Recognition, Visual - physiology; Reward; Verbal Learning - physiology; fMRI; hippocampus; cross-situational learning; computational modeling
• ISSN: 0960-9822; 1879-0445; 1879-0445
• DOI: 10.1016/j.cub.2018.02.042

When we encounter a new word, there are often multiple objects that the word might refer to [1]. Nonetheless, because names for concrete nouns are constant, we are able to learn them across successive encounters [2, 3]. This form of “cross-situational” learning may result from either associative mechanisms that gradually accumulate evidence for each word-object association [4, 5] or rapid propose-but-verify (PbV) mechanisms where only one hypothesized referent is stored for each word, which is either subsequently verified or rejected [6, 7]. Using model-based representation similarity analyses of fMRI data acquired during learning, we find evidence for learning mediated by a PbV mechanism. This learning may be underpinned by rapid pattern-separation processes in the hippocampus. Our findings shed light on the psychological and neural processes that support word learning, suggesting that adults rely on their episodic memory to track a limited number of word-object associations. •Subjects learned word-object associations across multiple exposures during fMRI•Learning involved regions associated with working memory and reward processing•RSA showed that learning was mediated by a propose-but-verify mechanism Using model-based representation similarity analyses of fMRI data, Berens et al. find evidence for cross-situational word learning mediated by a propose-but-verify mechanism in the hippocampus. This suggests that adults rely on their episodic memory to track a limited number of associations when learning new words across events.