Journal of Neuro-Oncology Award - Functional Mapping and Neural Oscillation Alteration in Processing of Finger Movement from Glioma-Infiltrated Motor Cortex

Introduction: The invasion of glioma cells through hijacking neuronal synapses would affect neural activities and signal transduction. It was assumed that the alteration at neuronal level could affect brain neural activities at cortex, thereby inducing function impairment. For the motor cortex, it was involved in the control of human body and limb movements, but the affection on neural oscillations and cortex network from glioma infiltration was still unclear.

Methods: To investigate this, two groups of patients were recruited: one with a glioma-infiltrated motor cortex and another with an unaffected motor cortex. Intraoperative functional mapping by electrical stimulation and high-density electrocortical signal recording were employed under awake craniotomy. We analyzed these neural oscillations from three perspectives: time-frequency features of electrical activities, motor circuit information flow, and decoding performance.

Results: It was found that from electrical stimulation, there were significant variations in the spatial distribution of positive cortical stimulation responses between the two groups. The variation was supported by the aberrant neural oscillations within the peritumoral motor cortex. Specifically, the task-related synchronization in the high-gamma band (60-140Hz) was suppressed, and the power across all frequency bands was reduced in the M1 hand area. The atypical motor information transmission patterns—characterized by discrete signaling pathways and delayed activation responses in the Gamma-3 band (90-120Hz)—suggest that gliomas functionally invade neural circuits within the motor cortex, displacing original conduction pathways. Consequently, this degrades the stability of neural encoding patterns for finger movement kinematics across various temporal-spatial scales in motor regions.

Conclusion : These findings set insights into the mesoscopic mechanism of motor cortex network remodelling from glioma infiltration, deepening our understanding of motor functional reconfiguration, balancing maximal resection with the preservation of neurological function, and advancing postoperative rehabilitation for patients with motor cortex gliomas.