Converging evidence for functional and structural segregation within the left ventral occipitotemporal cortex in reading

Proc Natl Acad Sci U S A. 2018 Oct 16;115(42):E9981-E9990. doi: 10.1073/pnas.1803003115. Epub 2018 Sep 17.

Abstract

The ventral occipitotemporal cortex (vOTC) is crucial for recognizing visual patterns, and previous evidence suggests that there may be different subregions within the vOTC involved in the rapid identification of word forms. Here, we characterize vOTC reading circuitry using a multimodal approach combining functional, structural, and quantitative MRI and behavioral data. Two main word-responsive vOTC areas emerged: a posterior area involved in visual feature extraction, structurally connected to the intraparietal sulcus via the vertical occipital fasciculus; and an anterior area involved in integrating information with other regions of the language network, structurally connected to the angular gyrus via the posterior arcuate fasciculus. Furthermore, functional activation in these vOTC regions predicted reading behavior outside of the scanner. Differences in the microarchitectonic properties of gray-matter cells in these segregated areas were also observed, in line with earlier cytoarchitectonic evidence. These findings advance our understanding of the vOTC circuitry by linking functional responses to anatomical structure, revealing the pathways of distinct reading-related processes.

Keywords: functional and structural MRI; quantitative MRI; reading; visual word form area; visual word recognition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain Mapping / methods*
  • Cerebral Cortex / physiology*
  • Female
  • Functional Laterality / physiology*
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Mental Processes / physiology*
  • Neural Pathways
  • Neuropsychological Tests
  • Occipital Lobe / physiology*
  • Psychomotor Performance
  • Reading*
  • Temporal Lobe / physiology*
  • Young Adult