Within and beyond the visual cortex: brain tumors induce highly sensitive plasticity of visual processing in whole-brain neural functional networks.

Vision is a key source of information input for humans, which involves various cognitive functions and a great range of neural networks inside and beyond the visual cortex. There has been increasing observation that the cognitive outcomes after a brain lesion cannot be well predicted by the attributes of the lesion itself but are influenced by the functional network plasticity. However, the mechanisms of impaired or preserved visual cognition have not been probed from direct function-execution conditions and few works have observed it on whole-brain dynamic networks. We used high-resolution electroencephalogram recordings from 25 patients with brain tumors to track the dynamical patterns of functional reorganization in visual processing tasks with multilevel complexity. By comparing with 24 healthy controls, increased cortical responsiveness as functional compensation was identified in the early phase of processing, which was highly localized to the visual cortex and functional networks and less relevant to the tumor position. Besides, a spreading wide enhancement in whole-brain functional connectivity was elicited by the visual word-recognition task. Enhanced early rapid-onset cortical compensation in the local functional networks may contribute to largely preserved basic vision functions, and higher-cognitive tasks are vulnerable to impairment but with high sensitivity of functional plasticity being elicited.