Recollection of verbal materials engages the default mode network more strongly than recollection of visual materials: An fMRI meta-analysis.

Episodic recollection—remembering past experiences—consistently activates the default mode network (DMN) in brain imaging studies, but whether the type of remembered content matters was unclear. This meta-analysis of 24 verbal and 19 visual recollection studies found that both forms engage the DMN, but verbal materials produce stronger and more widespread activation across all three DMN subnetworks than visual materials. Direct comparisons confirmed a verbal bias in every DMN subdivision, and separate analyses of words, objects, and scenes supported this pattern. The bias may arise because verbal recollection relies more on DMN-supported conceptual integration or semantic scaffolding. The verbal-visual dimension may be an important organizing principle of DMN function in episodic memory.

Study at a glance

Abstract

Functional neuroimaging studies consistently show that episodic recollection engages the default mode network (DMN), yet the extent to which this engagement varies with the representational content of retrieved information remains unclear. The present meta-analysis examined whether recollection of verbal and visual materials differentially recruits the DMN. Twenty-four verbal and 19 visual studies were included; recollection was operationalized using subjective measures, and network correspondence was assessed using the Yeo 17-network parcellation. Both forms of recollection engaged the DMN, but recollection of verbal materials showed stronger and more widespread recruitment across all three DMN subnetworks than recollection of visual materials. Direct contrasts likewise revealed consistent preferential associations for verbal relative to visual recollection across all DMN subdivisions. Separate analyses of word-, object-, and scene-based recollection further supported a verbal bias in DMN engagement. The bias may reflect a greater reliance of verbal recollection on DMN-supported conceptual integration, or semantic scaffolding, than visual recollection. More broadly, the findings suggest that differences associated with the verbal-visual dimension may constitute an important organizing principle of DMN function in episodic memory and may help account for variability across prior neuroimaging findings, with potential implications for other DMN-supported domains.