How does the “default mode” network contribute to semantic cognition?

• Published in: Brain and language Vol. 252; p. 105405
• Main Authors: Fernandino, Leonardo, Binder, Jeffrey R.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.05.2024
• Subjects: Brain - physiology; Cognition - physiology; Default Mode Network - diagnostic imaging; Default Mode Network - physiology; Humans; Semantics
• ISSN: 0093-934X; 1090-2155; 1090-2155
• DOI: 10.1016/j.bandl.2024.105405

•There is strong evidence that the DMN is involved in semantic cognition.•DMN areas contribute to semantics at the word, sentence, and discourse levels.•The DMN enables the construction of embodied situation models.•Situation models are implemented as dynamic recurrent neural assemblies.•These assemblies include modality-specific, multimodal and DMN cortical areas. This review examines whether and how the “default mode” network (DMN) contributes to semantic processing. We review evidence implicating the DMN in the processing of individual word meanings and in sentence- and discourse-level semantics. Next, we argue that the areas comprising the DMN contribute to semantic processing by coordinating and integrating the simultaneous activity of local neuronal ensembles across multiple unimodal and multimodal cortical regions, creating a transient, global neuronal ensemble. The resulting ensemble implements an integrated simulation of phenomenological experience – that is, an embodied situation model – constructed from various modalities of experiential memory traces. These situation models, we argue, are necessary not only for semantic processing but also for aspects of cognition that are not traditionally considered semantic. Although many aspects of this proposal remain provisional, we believe it provides new insights into the relationships between semantic and non-semantic cognition and into the functions of the DMN.