Fig. 1: Experimental design and devices.
From: High-resolution prosthetic hearing with a soft auditory brainstem implant in macaques
a, Left: schematic of an NHP brain. The soft ABI is implanted on the cochlear nucleus; the soft ECoG records cortical responses from the auditory cortex. Right: NHP behavioural task in response to electrical or acoustic stimulation. Created with BioRender.com (https://BioRender.com/y29o453) and using a brain image from Adobe Stock. b, Photograph of the integrated soft ABI and its connectors: an Omnetics connector is embedded in a PEEK pedestal and connected to the soft ABI. An imaging marker and resorbable insertion spine are also visible. c, Integrated soft ECoG device: 29 electrodes (300-µm diameter) that record cortical signals. d, Close-up of the soft ABI: 11 electrodes (100-µm diameter). Right inset: FlexComb connector22. e,f, In vitro characterization23 of the soft ABI (e) and EcoG (f). Left: EIS measurement, where data points represent the average and bars represent standard errors for all electrodes. Right: VT in response to a 100-µA biphasic current pulse. The thick blue line represents the average and light lines represent individual electrodes. g, Scanning electron microscopy (SEM) images of micropatterned ABI electrodes and interconnects. Top left: image of one ABI electrode and associated interconnect. Red frame, close-up of an interconnect; green frame, close-up of the electrode. Bottom right: colourized SEM of the electrode and encapsulation of the platinum layer within the polyimide dielectric layers.
