Brain cells and neuronal networks

Display Omitted Microengineering and neuroscience come together to great advantage.Controlled microenvironments unveil brain cell response to isolated stimuli.Artificial microenvironments may reveal some properties of brain cells.Microengineered substrates guide neuronal growth in order to build networks.3D surface structuring leads to advanced multiplexed electrophysiology methods. This review is an attempt to shed light on the wealth of the close association between micro/nanotechnologies and neurobiology. With this aim, we have identified four specific areas in the field of neuroscience that fruitfully exploit the conceptual approaches of physics together with the engineering tools originally developed for microelectronics. Each of these areas are developed in this review within a dedicated section. The first section "Isolating environmental parameters" illustrates how fabricating specific microenvironments allows one to isolate the cell response to specific physiological stimuli, either chemical or topographical. In a complementary way, the section "Revealing the properties of brain cells" shows how the design of rather artificial in vitro culture conditions can give precious insights into the field of neurobiology. The acquired knowledge concerning the response of isolated neurons to external physical cues may inspire methodologies for mastering the architecture, polarity and connectivity of in vitro neuronal assemblies. These aspects are developed in the section "Controlling neuronal architectures". Finally, a section entitled "Instrumentation of neuronal networks" reports some salient examples of recent innovative achievements in the field of neuron-electronic interfacing, illustrating how the issue of neuronal contact with micro-structured environments supports the development of advanced multiplexed electrophysiology methods. We will finally conclude this review by introducing some medical applications originating from the contribution of micro/nanotechnologies to the field of neuroscience. Our take-home message is that configuring the cellular microenvironment using microengineering tools has a strong positive impact in neuroscience at different levels, from the most fundamentals of cellular neurobiology to medical applications.

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