The "two-brain" approach reveals the active role of task-deactivated default mode network in speech comprehension.
Lanfang Liu, Hehui Li, Zhiting Ren, Qi Zhou, Yuxuan Zhang, Chunming Lu, Jiang Qiu, Hong Chen, Guosheng Ding
Cerebral Cortex October 20, 2022 DOI: 10.1093/cercor/bhab521 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational neuroimaging study Peer reviewed |
|---|---|
| Population | Listeners and speakers during spoken language comprehension |
| Topics | Default mode network |
| Keywords | Neural coupling Speech comprehension Two-brain |
| Key findings | Despite being deactivated and anticorrelated with the language and executive control networks, both anterior and posterior DMN regions in listeners were temporally coupled with homologous speaker networks, and this coupling persisted after controlling for listener-listener intersubject correlation. Posterior DMN coupling strength positively correlated with listeners' speech comprehension. The authors propose the DMN acts as an internal module cooperating with externally oriented modules, potentially supporting transformation of acoustic signals into internal mental representations. |
Abstract
Exhibiting deactivation and anticorrelation with task-positive networks, the default mode network (DMN) has been traditionally thought to be suppressed to support externally oriented cognitive processes during spoken language comprehension. In contrast, recent studies examining listener-listener intersubject correlation (ISC) have proposed an active role of DMN in language comprehension. How can we reconcile those seemingly conflicting results? This study adopted a "two-brain" paradigm and combined "within-brain" and "across-brain" analyses to address this issue. We found, despite being deactivated and anticorrelated with the language network (LN) and executive control network (ECN), both the anterior and posterior DMN in the listeners' brains were temporally coupled with the homologous networks in the speaker's brain. Interestingly, the listener-speaker neural couplings persisted even after controlling for listener-listener ISC. Moreover, the coupling strength of posterior DMN positively correlated with the listeners' speech comprehension. Further dynamic causal modeling showed that the LN and ECN, the anterior DMN, and the posterior DMN occupied the bottom, intermediate, and top layers of a hierarchical system, respectively. We suggest the DMN may primarily serve as an internal module that cooperates with the externally oriented modules, potentially supporting the transformation of external acoustic signals into internal mental representations during successful language comprehension.
Comparable studies
Other experimental studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Functional connectivity of default mode network components: Correlation, anticorrelation, and causality Healthy subjects | 2008 | Observational study using resting-state fMRI and seed correlation analysis | |
| Patterns of Brain Activity Supporting Autobiographical Memory, Prospection, and Theory of Mind, and Their Relationship to the Default Mode Network Healthy subjects | 2009 | Experimental study using fMRI | |
| Dynamic reconfiguration of the default mode network during narrative comprehension Human subjects | 2016 | Experimental study | |
| Broadband Cortical Desynchronization Underlies the Human Psychedelic State Healthy human participants | 2013 | Experimental study | |
| The brain on art: intense aesthetic experience activates the default mode network Human observers | 2012 | Observational study with fMRI and behavioral analysis |
Citations in the library
Cites 8
- Functional connectivity of default mode network components: Correlation, anticorrelation, and causality Human Brain Mapping January 24, 2008
- Patterns of Brain Activity Supporting Autobiographical Memory, Prospection, and Theory of Mind, and Their Relationship to the Default Mode Network Journal of Cognitive Neuroscience July 6, 2009
- The default mode network: where the idiosyncratic self meets the shared social world Nature Reviews Neuroscience January 22, 2021
- Dynamic reconfiguration of the default mode network during narrative comprehension Nature Communications July 18, 2016
- The default mode network and social understanding of others: what do brain connectivity studies tell us Frontiers in Human Neuroscience 2014
and 3 more in the library