Neurophysiology and computational neuroscience

Abstract

Issues 3–4 of the 200th volume of Experimental Brain Research are devoted to neurophysiology and computational neuroscience. Neurophysiology has remained a major focus of Experimental Brain Research since the founding of the journal in 1966 by an editorial board that included Sir John Eccles. Issue 3 continues this long tradition by including two reviews and Wve original articles that use or consider neurophysiological approaches to provide insights into sensory processing and sensorimotor integration by the nervous system. Issue 3 begins with a review by Green and Angelaki regarding the processing of sensory inputs by the vestibular system. The vestibular system is vital for motor control and spatial motion perception. Over the years, studies of the vestibular system have served as an excellent model framework for investigating the basic strategies by which sensory signals are transformed into central representations that give rise to behavior. For this reason, Experimental Brain Research has published over 1,000 manuscripts related to the vestibular system. In the review by Green and Angelaki, the authors describe recent advances in identifying the neural correlates for a number of fundamental computations and transformations of vestibular signals implemented by brainstem–cerebellar circuits. These include the sensorimotor transformations for reXex generation, the neural computations for inertial motion estimation, the distinction between active and passive head movements, as well as the integration of vestibular and proprioceptive information for body motion estimation. The authors emphasize why the study of these problems has revealed important organizational principles (e.g., the concept of “internal models”, multisensory integration, reaVerence, reference frame transformations) that are generally relevant for all sensorimotor systems. Although explicit neural correlates for such computations (e.g., internal models) have often been diYcult to identify in other systems (e.g., limb control circuits), this review emphasizes the signiWcant advances made in so doing in the vestibular system. As a result, studies of this system continue to have great potential to yield new insights into common neural processing strategies relevant for both reXexive and goal-directed, voluntary movement as well as perception. A second review by Rizzolatti and Fabbri-Destro on the mirror neurone system begins with a short historical account of the important role of Experimental Brain Research in publishing much of the early animal work on mirror neurons at the end of the 1980s and early 1990s. Professor Rizzolatti recalls that in those days, Nature failed to recognize the importance of the work and declined publication. He was in good company: the same journal had earlier rejected the Nobel prize-winning work of Otto Krebs on the citric acid cycle. The bulk of the review focuses on the rapidly expanding literature on the mirror neurone system in humans which has been made possible by advances in neuroimaging, transcranial brain stimulation and clever behavioral experiments. These have led to an explosion of interest that had never been anticipated in the early days. Indeed, the relevance of the mirror neuron system to cognition J. C. Rothwell (&) UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK e-mail: j.rothwell@ion.ucl.ac.uk