Abnormality of the pulvinar in posterior cortical atrophy: A multimodal MRI study

Abstract

AbstractBackgroundAlthough the pulvinar is known for its extensive connections with both ventral and dorsal visual streams, details of pulvinar functional connectivity in the setting of posterior cortical atrophy (PCA) remain unclearTo study pulvinar functional connectivity and relevant associations with higher visual dysfunction in PCA.MethodA total of 29 patients with PCA and 30 normal controls were recruited. Each participant underwent comprehensive neuropsychological assessment and both structural and resting‐state functional MRI scanning. Voxel‐based morphometry (VBM) and seed‐based functional connectivity analyses were conducted to assess pulvinar gray matter volume as well as connectivity between the pulvinar and whole brain regions. A partial correlation analysis was performed to analyze neuropsychological test and pulvinar imaging data.ResultCognitive and visual functions including visuospatial processing, visual perception, episodic memory, and naming were impaired among PCA patients. Marked pulvinar atrophy was noted in PCA patients. Furthermore, functional connectivity between the pulvinar and precuneus was significantly decreased in PCA patients as compared to normal controls (FWE corrected; P<0.001). Left pulvinar gray matter volume was found to associate with object agnosia (r = 0.42, P<0.05) and right–left disorientation (r = 0.29, P<0.05) among PCA patients. The bilateral pulvinar region was found to associate with Boston Naming Test (left, r = 0.51, P = 0.015; right, r = 0.46, P = 0.03) and Activities of Daily Living (left, r = ‐0.46, P = 0.019; right, r = ‐0.53, P = 0.006) scores. Correlation analyses did not reveal significant findings concerning functional connectivity.ConclusionOur findings confirm pulvinar degeneration and its contributions in the setting of PCA.