ABSTRACT
From the vantage point of 1981, advances in our understanding of glial cells over the last 20 years seem at once significant, provocative and high in promise. It is sobering to remember that at that time speculation about their role included a spectrum of romantic possibilities, from blood-brain barrier to memory, from constituting the total extracellular space of the brain to playing a key role in learning, from being essential for the neuronal action potential to producing impulses themselves, from ferrying vital materials into and out of neurones to having no function at all other than support. Unfortunately, the ratio of speculation to sound experimental observations was so high that, apart from continuing contributions from anatomists, to be interested in glia was almost disreputable, somewhat akin to dabbling in parapsychology or memory transfer.
