Distinct neural substrates of visuospatial and verbal-analytic reasoning as assessed by Raven's Advanced Progressive Matrices

Abstract

Recent studies revealed spontaneous neural activity to be associated with fluid intelligence (gF) which is commonly assessed by Raven's Advanced Progressive Matrices, and embeds two types of reasoning: visuospatial and verbal-analytic reasoning. With resting-state fMRI data, using global brain connectivity (GBC) analysis which averages functional connectivity of a voxel in relation to all other voxels in the brain, distinct neural correlates of these two reasoning types were found. For visuospatial reasoning, negative correlations were observed in both the primary visual cortex (PVC) and the precuneus, and positive correlations were observed in the temporal lobe. For verbal-analytic reasoning, negative correlations were observed in the right inferior frontal gyrus (rIFG), dorsal anterior cingulate cortex and temporoparietal junction, and positive correlations were observed in the angular gyrus. Furthermore, an interaction between GBC value and type of reasoning was found in the PVC, rIFG and the temporal lobe. These findings suggest that visuospatial reasoning benefits more from elaborate perception to stimulus features, whereas verbal-analytic reasoning benefits more from feature integration and hypothesis testing. In sum, the present study offers, for different types of reasoning in gF, first empirical evidence of separate neural substrates in the resting brain.

Figure 1

Mean GBC values averaged across participants by top percentages of voxels. High GBC values are shown in warm colors (red), low GBC values are shown in cool colors (blue).

Figure 2

Regions with GBC values showing significant correlations with the RAPM score after the effects of sex, age and FD scores were regressed out. Clusters containing more than 122 contiguous voxels survived the AlphaSim correction. Abbreviations: MFG, middle frontal gyrus; MPFC, medial prefrontal cortex; dACC, dorsal anterior cingulate cortex.

Figure 3

Regions with GBC values that were significantly correlated with the visuospatial subset score after regressing out the following covariates: sex, age, FD and the verbal–analytic subset score. Clusters containing more than 116 contiguous voxels survived the AlphaSim correction. Abbreviation: ITG, inferior temporal gyrus.

Figure 4

Correlational patterns between the GBC value and the verbal–analytic subset score after the effects of sex, age, FD and the visuospatial subset score were regressed out. Clusters containing more than 105 contiguous voxels survived the AlphaSim correction. Abbreviations: IFG, inferior frontal gyrus; dACC, dorsal anterior cingulate cortex; SMA, supplementary motor area; TPJ, temporoparietal junction; ITG, inferior temporal gyrus.

Figure 5

The upper panel depicts the interaction regions between visuospatial and verbal-analytic reasoning. Clusters containing more than 116 contiguous voxels survived the AlphaSim correction. The green dotted line shows the brain-behavioral GBC correlation regions of visuospatial and verbal-analytic reasoning; these correlation regions partially overlap; that is, they show a significant brain-behavioral correlation and, at the same time, a significant interaction of visuospatial and verbal-analytic reasoning. The bottom panel depicts correlational patterns between: (a) the primary visual cortex’s (PVC) GBC value and the visuospatial subset score; (b) the PVC’s GBC value and the verbal–analytic subset score; (c) the right inferior frontal gyrus’s (rIFG) GBC value and the visuospatial subset score; and (d) the rIFG’s GBC value and the verbal–analytic subset score. These visuospatial and verbal-analytic reasoning scores were centered using z-transform. The elliptic boundary defines the 95% confidence region.

Figure 6

The visuospatial and the verbal-analytic scores correlate with both the within- and between- network GBC (WNC/ BNC GBC) of primary visual cortex (Cuneus) and inferior frontal gyrus (IFG) in the visual network and frontal-parietal multiple demand regions (i.e., the frontal-parietal network, dorsal attention network and ventral attention network).

Figure 7

The correlations between the RAPM subset scores and the network-wise FCs in frontal and parietal regions. (a) The network-wise correlations of visuospatial and (b) verbal-analytic subsets; (c) the network-wise correlation differences between the visuospatial and the verbal-analytic subsets: the FCs within the frontal-parietal network (FPN) and the FCs between FPN and salience network (SAN) have significant different network-wise correlations with the two RAPM subset scores (false discovery rate corrected, p < 0.05); (d) these analyses pertain to the frontal and parietal multiple demand regions which includes the FPN, cingulo-opercular network (CON), SAN, dorsal attention network (DAN) and ventral attention network (VAN).