An animal model of auditory cortex prostheses

Experiments aimed at rehabilitating deaf and blind patients with cortical prostheses were first conducted decades ago, but epicortical electrodes allowed only crude information transfer. Here we report that in Mongolian gerbils with electrodes implanted in input layers of the primary auditory cortex, spatial, temporal and spatiotemporal variations in intracortical stimulation all lead to perceptual differences as evidenced by discrimination training. For some stimulus regimes discrimination learning was as fast as with intracochlear stimulation in this animal. Intracortical stimulation induced field potentials and 2-deoxyglucose labeling patterns in primary auditory cortex similar to those induced by auditory click or tone stimuli, respectively. Given the common organization principles of neocortical areas, these results are presumably also of significance to prostheses interfacing with visual cortex.