Technical steps towards one-to-one electrode–neuron interfacing with neural circuits reconstructed in vitro

The electrical interfacing with cultured networks of neurons by means of multielectrode arrays (MEAs) is an area of intensive research given the potential of this technique to aid in the extraction of the algorithms that support neurocomputation in brain tissue. To this end, we have previously described the polymer-on-multielectrode technology (PoM [E. Claverol-Tinturé, M. Ghirardi, F. Fiumara, X. Rosell, J. Cabestany. Multielectrode arrays with elastomeric microstructures for neuronal patterning towards interfacing with uni-dimensional neuronal networks. J. Neural Eng. 2(2) (2005) L1–7] and demonstrated single-site recordings from patterned invertebrate cells. The realisation of the full potential of PoM is dependent on its successful application to vertebrate cells and to the recording of activity in ensembles of neurons. Here, we describe progress in these directions, specifically towards the development of vertebrate neuronal cultures devoid of glial layers compatible with PoM devices, the connection of pairs of invertebrate neurons threading microchannels and the recordings of synaptic and spike-like activity.