Intrinsic Functional Connectivity Patterns of The Object-Selective Visual Areas.

Abstract

Introduction: It has been shown by numerous investigations that the occipitotemporal area has a particular object perception area called the lateral occipital complex, which is composed of lateral occipital (LO) and posterior fusiform (pF) cortices. The aim of this study is to examine the intrinsic functional connectivity (iFC) patterns of the object-selective LO and pF regions in order to shed light on the underlying neural mechanisms of object recognition.

Methods: 15 healthy participants were included in the study. A standard localizer task was used to identify LO and pF regions. Magnetic resonance imaging (MRI) data were collected using two different imaging protocols: high-resolution anatomical image and functional MRI (fMRI) data. Data preprocessing steps were carried out in accordance with standard procedures. After determining the LO and pF regions with activation analyses on the task-based fMRI data, the iFCs of these regions were investigated with functional connectivity analyses carried out on the resting-state fMRI recording.

Results: iFC analyzes revealed that LO and pF regions have different connectivity patterns. Lateral occipital had a widely distributed connectivity network, whereas pF showed a more localized connectivity pattern. Lateral occipital had more extensive occipitotemporal, occipitoparietal and motor connections compared to pF. In contrast to this distribution pattern, the connections of the right and left LO were generally concentrated on the ipsilateral sides, while the connections of the pF were bilateral.

Conclusion: The results of the study revealed complex iFC patterns of the LO and pF differentiating their functional roles in object perception/recognition. While the pF revealed bilaterally distributed iFC along the ventral visual stream, the extensive and lateralized iFC of the LO suggests its role in integrating visual information including object-related attention and action recognition.