Strategies for implanting brain-computer interfaces in the hand motor cortex: from neural foundations to individualized assessment and target planning

Invasive brain-computer interface (BCI) reconstructs hand movement functions by decoding cortical neural signals, providing patients with a new treatment approach. Precise microelectrode arrays implantation is the fundamental prerequisite for obtaining high-quality and stable neural signals, requiring the surgeon to deeply understand the neural anatomical basis of the primary motor cortex hand area (M1-HAND) and to comprehensively apply multimodal imaging, functional localization, and surgical planning techniques to develop individualized target plan for each patient. This article systematically reviews the cortical neural basis of hand movement control, and compares the advantages and limitations of individualized functional mapping methods such as functional magnetic resonance imaging (fMRI), navigated transcranial magnetic stimulation (nTMS), and diffusion tensor imaging (DTI), and summarizes the improved methods for optimizing the hand area and the 10-20 system coordinates. For clinical assessment, this article proposes a multi-level assessment framework covering the neural signal, task performance, functional outcome, and quality of life. This article aims to provide a systematic reference framework from the neural basis, individualized mapping, implantation strategy to the assessment system for the clinical implementation of BCI for hand movement function recovery, and promote invasive BCI from engineering verification to clinical transformation.