Elena Galea – Universitat Autònoma de Barcelona (UAB)
Astrocytes are cells of the central nervous system (CNS). Although astrocytes are less popular than neurons, it is worth emphasizing that they are an integral part of neuronal circuits. According to the prevalent view, neurons are the CNS cells that carry the complex computations subserving coding, complex behaviors, and higher brain functions. In this perspective article we ask whether, beyond providing metabolic and homeostatic support to neurons, astrocytes are fundamental to CNS coding. If they do, specific questions are whether there are niche(s) in CNS coding that would particularly profit from astrocyte idiosyncrasies, and whether the impressive techniques and theoretical armamentarium deployed for neurons could be used—and are sufficient—to unravel possible astrocyte-based coding. Pioneering theoreticians in neuroscience argued that anatomical features provide valuable insights about how the CNS operates because ‘the nervous system is a product of evolution, not design. The computational solutions evolved by nature may be unlike those that humans would invent, if only because evolutionary changes are always made within the context of a design and architecture that already is in place’. Thus, we reason that the unique anatomical arrangement between astrocytes and neurons might be part of computational solutions refined by evolution that have made the brain a highly efficient task performing system, for the brain is capable to carry out operations at a low energy expense and with a high speed unmatched by computers. In this article we explore the possible operations performed by astrocytes to efficiently integrate information from different neurons, we explain the implications of these tasks in higher brain functions, as well an in the modeling of neural circuits with artificial intelligence, and we present a roadmap to advance knowledge of astrocytes as building blocks of neural circuits.