Preprint / Version 1

Comparative Analysis of Movement Direction Decoding: M1 vs. PMd Neural Populations in Macaque Monkeys


  • Jesse Lavin Northern Valley Regional High School at Demarest
  • Omar Tawakol



M1, PMd, Population Vector, MLE, DSI, Confusion Matrix, Raster Plot


To improve the precision of neural decoding for applications like prosthetic device control, a critical need arises for more accurate decoding methods. Various brain regions have been identified as potential sources for encoding the direction of movement, presenting a fundamental question: which neural population provides superior decoding accuracy? This research addresses this question by undertaking a comparative analysis of decoding accuracy between two prominent neural populations: the primary motor cortex (M1) and the dorsal premotor cortex (PMd). While our study initially suggested a striking disparity, indicating that M1 neurons might exhibit significantly greater tuning specificity towards the direction of executed movements when contrasted with PMd neurons, our subsequent rigorous analysis found no statistically significant difference in their tuning specificity. In light of these revelations, I determined that both regions may be employed to empower individuals with motor disabilities to control external devices easily using their own neural signals.


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