Varieties of semantic cognition revealed through simultaneous decomposition of intrinsic brain connectivity and behaviour

Abstract

propensity to generate particular configurations of such components, and these 6 trait-level differences may relate to individual differences in semantic cognition. 7We tested this view by exploring how variation in intrinsic brain functional 8 connectivity between semantic nodes in fMRI was related to performance on a 9 battery of semantic tasks in 154 healthy participants. Through simultaneous 10 decomposition of brain functional connectivity and semantic task performance, 11we identified distinct components of semantic cognition at rest. In a subsequent 12 validation step, these data-driven components demonstrated explanatory power 13 for neural responses in an fMRI-based semantic localiser task and variation in 14 self-generated thoughts during the resting-state scan. Our findings showed that 15 good performance on harder semantic tasks was associated with relative 16 segregation at rest between frontal brain regions implicated in controlled 17 semantic retrieval and the default mode network. Poor performance on easier 18 tasks was linked to greater coupling between the same frontal regions and the 19 anterior temporal lobe; a pattern associated with deliberate, verbal thematic 20 thoughts at rest. We also identified components that related to qualities of 21

Converging evidence for the role of transmodal cortex in cognition

“…Vatansever et al (2) found that the DMN is active after participants have acquired the rule in the WCST, corresponding to periods when memory input is most relevant for task performance. Although determining the specific functional processes of the metastates identified by Vidaurre et al (1) is challenging since they occur at rest, we do note recent studies have linked patterns of integration at rest within both the DMN and FPN as important for different types of spontaneous thoughts (21)(22)(23)(24)(25). It is possible, therefore, that the fractional occupancy of the transmodal metastate may reflect types of spontaneous thought that derive their content from memory (26).…”

Divergent effects of healthy ageing on semantic knowledge and control: Evidence from novel comparisons with semantically impaired patients

“…Although an old-age deficit in semantic control has not been reported previously, it is consistent with our understanding of changes in neural structure and function in later life. Semantic control is underpinned by a network of regions including inferior parietal, posterior temporal, and, most prominently, inferior prefrontal cortex (Jefferies, 2013;Noonan et al, 2013;Vatansever et al, 2017). Inferior prefrontal cortex shows large agerelated declines in volume in later life (Fjell et al, 2009;Raz et al, 1997Raz et al, , 2005, and changes in functional activation are also frequently observed in this region (Cabeza, 2002;Grady, 2012).…”

Interactions between the neural correlates of dispositional internally directed thought and visual imagery

“…Our analysis suggests that visual imagery is linked to functional connectivity between the precuneus and a lateral fronto-temporal network that contributes to multi-modal forms of semantic cognition [72]. Contemporary accounts suggest that the anterior temporal lobe supports cognition with different representational features (pictures versus words, [73] for a review). Generally therefore, our results are consistent with the hypothesis that the production of visual imagery depends upon the integration of a system important for visual processing (the precuneus) with regions supporting multi-modal elements of cognition (lateral temporal and frontal cortex).…”