Clinical applications of brain implantable devices for recording and interpreting electrical signals from the cortex have grown rapidly in the last decade. For long-term cortical recording, a micro-electrocorticographic (microECoG) electrode and universal platform were developed and evaluated. The electrode diameters and inter-electrode distances of the new device are on the order of 100s of microm, significantly smaller than general ECoG grids, and do not require penetrating the brain. Acute recordings from the device demonstrated that independent brain activity could be recorded from electrodes with a spatial resolution of 1 mm.