Conformable enhancement-mode, internal ion-gated organic electrochemical transistor (e-IGT): A) Micrograph displaying the top view of an e-IGT (top). Scale bar, 5 mm. Ultra-flexible, ultra-thin e-IGT array conforming to the surface of a human hand (bottom). B) Optical micrograph of an e-IGT-based device with four transistors for LFP and spike recording. The anchor hole facilitates insertion of the conformable device into deep layers of cortex. Scale bar, 80 mm. Credit: Columbia Engineering