1. An interface for selectively making electrical contact to a plurality of neural cells in a biological neural network, said interface comprising: a) a membrane having a thickness of less than 0.5 mm and including a plurality of channels passing through said thickness of said membrane, said membrane disposed in proximity to said biological neural network, whereby said neural cells are capable of migrating into said channels; and b) a plurality of first electrodes disposed within said channels; wherein sufficient space is present in said channels to permit migration of at least one of said neural cells into said channels.