Failure in developing high-level visual functions after occipitoparietal lesions at an early age: a case study

Abstract

Previous functional magnetic resonance imaging (fMRI) studies have identified several regions in the ventral visual pathway that are specialized for processing faces, words and general objects. However, little is known about the origin of the functional selectivity of these regions. Here, we reported a pediatric patient who suffered a left occipitoparietal lesion in the first year after birth from a subdural hematoma. After the hematoma was removed at the age of six, the hemianopia in the right visual field was alleviated, and no obvious deficits in low-level vision were observed in the patient at the age of twelve. In line with the behavioral observations, meridian mappings with fMRI showed that the early visual cortex of the left hemisphere was significantly activated, which was similar to that of the intact right hemisphere. However, the left ventral temporal cortex failed to show selective responses for faces, words and objects, which were in contrast to the normal selective responses for these objects in the right counterpart. Therefore, it is likely that the development of object selectivity in the ventral temporal cortex depends on visual inputs from the early visual cortex at an early age.

Keywords: Cortical lesion; Development; Early visual cortex; Object selectivity; Ventral visual pathway.