This chapter 3 provides an insight into the use of in vitro neuronal cultures and electronic transduction methods to study the neuron behavior. Understanding the mechanisms that generate field potentials in neurons grown on semiconductor chips is essential for implementing effective neuro‐electronic devices. Field effect transistors (FETs) are used widely as neurotransducers, and their implantation techniques and methods for improving signal‐to‐noise ratio are reviewed. Complementary metal oxide semiconductor (CMOS) micro array structures can be used to acquire spatially resolved information from the distribution of activity of neuronal and cellular cultures. The role of microelectronic arrays (MEAs) in the in vitro study of neurons is examined including a review of important design considerations such as cellular environment, surface conditioning, charge transfer, interfaces and fabrication processes. The micro total analysis system (μTAS) and microfluidic devices are emerging concepts, with the latter offering new avenues for oriented neural networks and chemical communication, and interactions with cells. The chapter concludes with a review of how MEAs and other in vitro neuronal cultures have been used to create biosensors for neuroscience applications.