Abstract
Introduction: Human cognition is organized in distributed networks in the brain. While distinct specialized networks have been identified for different cognitive functions, previous work also emphasizes the overlap of some key cognitive domains in higher level association areas (1). A better understanding of the overlap and dissociation of these networks during different cognitive tasks may provide insight into how resources are flexibly redistributed during human cognition.
Methods: We present data from 22 healthy, native German speakers (11 female, mean age 27.9 ±3.28 years), who took part in an fMRI experiment combining prototypical tasks of the larger domains attention, language and social cognition. Within a single scanning session, volunteers performed a Posner-like attentional reorienting task, a lexical decision task, and a perspective taking task; counterbalanced sessions were repeated 12 times. Applying whole-brain multivariate activity and connectivity approaches, specifically group-wise spatial independent component analysis and correlational psychophysiological interaction analysis (2), we provide a spatio-temporal characterization of multiple large-scale, overlapping networks across cognitive domains.
Results: We characterized 11 overlapping high-order cognitive networks across tasks. As a key finding, we demonstrate that high-order functional network interactions increase with increasing cognitive complexity across the three domains. Interaction patterns demonstrate a common core structure across domains, which includes the multiple demand network, default mode subnetworks, and two lateralized fronto-parietal networks, as well as dissociable domain-specific activity and connectivity, that is, ventral attention network specific to attentional reorientation, semantic network specific to lexical decision making, and multiple domain general networks to social cognition.
Conclusions: In line with recent multi-task fMRI studies (3,4), we show a common functional structure across tasks. Extending previous work, we further present specific network activity and interactions that dissociate each domain. We show that network interactions change dynamically, increasing with increased cognitive complexity across cognitive domains, and, in the context of tasks, their activity does not strictly support a task-positive and task-negative dichotomy.
References:
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2. Fornito A, Harrison BJ, Zalesky A, Simons JS. Competitive and cooperative dynamics of large-scale brain functional networks supporting recollection. Proc Natl Acad Sci. 2012;109(31):12788-12793. doi:10.1073/pnas.1204185109
3. Cole MW, Bassett DS, Power JD, Braver TS, Petersen SE. Intrinsic and Task-Evoked Network Architectures of the Human Brain. Neuron. 2014;83(1):238-251. doi:10.1016/j.neuron.2014.05.014
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