Poster A52, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Multimodal characterization of ventro-occipito-temporal reading regions
Garikoitz Lerma-Usabiaga1, Manuel Carreiras1,2, Pedro M. Paz-Alonso1; 1BCBL. Basque Center on Cognition, Brain and Language., 2IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
The ventral occipito-temporal (vOT) association cortex significantly contributes to recognize different types of visual patterns. It is widely accepted that a subset of this circuitry, including the visual word form area (VWFA), becomes trained to perform the task of rapidly identifying word-forms. An important open question is the connectivity of the region to other language areas. While some authors report connections between the vOT and the posterior parietal cortex via the vertical occipital fasciculus, others highlight its more anterior connections through the arcuate fasciculus. Characterizing the vOT connectivity pattern can be critical to shed further light on the computational role of the VWFA. We present the results of a multimodal (functional, diffusion-weighted and quantitative) MRI study with a sample of 100 young adults aimed at investigating the functional and structural connectivity patterns of the vOT reading regions. To examine how functional contrasts selection influence the location of the VWFA, we used the most relevant contrasts reported in the literature. Furthermore, due to the large intraindividual variability present in previous studies, our analyses were performed at the individual-subject level, and half of the subjects were scanned twice to check for test-retest reliability. Our results revealed a functional gradient across different contrasts that goes along the anterior-posterior and medial-lateral axes in the vOT, and that might explain the differences in structural connectivity previously reported. We propose a new subdivision of the vOT reading regions, and a reproducible procedure of interest for researchers working in this area.
Topic Area: LANGUAGE: Other