ECoG

Published in Cell Reports Methods on June 12, 2026, the study presents high-density micro-electrocorticography arrays that integrate silicone elastomers (optical transparency, repeated penetration with intracortical arrays) and polyimide films (fine photolithographic feature definition) for multi-scale studies of brain activity. The combination facilitates high-throughput functional mapping to identify targets and insertion of intracortical arrays for dense local sampling. The authors demonstrated functional mapping in rats, cats and marmosets, guiding multi-area laminar recordings, and demonstrated local and feedforward optogenetic stimulation to investigate cortico-cortical interactions.

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.

A Neurosurgical Focus paper tested Precision Neuroscience's 1,024-channel Layer 7 micro-ECoG array in four awake-craniotomy patients. Four-word speech classification reached 77.5% accuracy and four-direction cursor classification reached 78% to 84%, with no device-related adverse events reported during the procedures. The small, short intraoperative study was a feasibility test rather than a pivotal motor-restoration trial.