Understanding the mechanisms that generate field potentials (FPs) by neurons grown on semiconductor chips is essential for implementing neuro-electronic devices. Earlier studies emphasized that FPs are generated by current flow between differentially expressed ion channels on the membranes facing the chip surface, and those facing the culture medium in electrically compact cells. Less is known, however, about the mechanisms that generate FPs by action potentials (APs) that propagate along typical non-isopotential neurons. Using Aplysia neurons cultured on floating gate-transistors, we found that the FPs generated by APs in cultured neurons are produced by current flow along neuronal compartments comprising the axon, cell body, and neurites, rather than by flow between the membrane facing the chip substrate and that facing the culture medium. We demonstrate that the FPs waveform generated by non-isopotential neurons largely depends on the morphology of the neuron.
Bibliographical noteFunding Information:
This study was supported by a grant from the Future and Emerging Technologies arm of the 5th IST Programme (No. IST-1999-29091). Parts of the study were carried out at the Charles E. Smith Family Laboratory for Collaborative Research in Psychobiology. M.E. Spira is the Levi DeViali Professor in Neurobiology.
- Field potential
- Neuro-electronic hybrids