Utrecht University

A team led by the UMC Utrecht Brain Center in the Netherlands analyzed 8 participants with high-density electrocorticography (ECoG) grids of 64 to 128 electrodes and found that a well-positioned 32-electrode grid classified 12 Dutch words with 76 ± 16% accuracy, comparable to 75 ± 17% for the larger grids. The best placement was vertical and centered on the central sulcus. Speech brain-computer interfaces aim to restore communication to people paralyzed and unable to speak, but larger grids carry higher surgical risk. The participants were not paralyzed and testing was limited to a fixed word set.