Showing papers by "Sacha B. Nelson published in 2013"
Technical University of Madrid1, Spanish National Research Council2, University of Pennsylvania3, Washington University in St. Louis4, Pierre-and-Marie-Curie University5, Universidad Miguel Hernández de Elche6, RWTH Aachen University7, New York University8, Max Planck Society9, Hungarian Academy of Sciences10, University of Pittsburgh11, Stanford University12, École Polytechnique Fédérale de Lausanne13, Icahn School of Medicine at Mount Sinai14, Cold Spring Harbor Laboratory15, University of Debrecen16, National Institutes of Health17, Technische Universität München18, German Cancer Research Center19, Brandeis University20, Boston University21, French Institute of Health and Medical Research22, University of California, San Francisco23, University of California, San Diego24, Yale University25, George Washington University26, University of Göttingen27, University of Szeged28, University College London29, Tufts University30, Wenzhou Medical College31, Howard Hughes Medical Institute32, Krasnow Institute for Advanced Study33
TL;DR: A possible taxonomical solution for classifying GABAergic interneurons of the cerebral cortex based on a novel, web-based interactive system that allows experts to classify neurons with pre-determined criteria is described.
Abstract: A systematic classification and accepted nomenclature of neuron types is much needed but is currently lacking. This article describes a possible taxonomical solution for classifying GABAergic interneurons of the cerebral cortex based on a novel, web-based interactive system that allows experts to classify neurons with pre-determined criteria. Using Bayesian analysis and clustering algorithms on the resulting data, we investigated the suitability of several anatomical terms and neuron names for cortical GABAergic interneurons. Moreover, we show that supervised classification models could automatically categorize interneurons in agreement with experts' assignments. These results demonstrate a practical and objective approach to the naming, characterization and classification of neurons based on community consensus.
727 citations
TL;DR: Using cell-type-specific projection mapping with synaptic resolution, this work observed the convergence of separate sensory and basilar pontine pathways onto individual granule cells and mapped this convergence across cerebellar cortex, providing evidence that the convergent basilar Pontine pathways carry corollary discharges from upper body motor cortical areas.
Abstract: Learning a new motor skill, from riding a bicycle to eating with chopsticks, involves the cerebellum—a structure located at the base of the brain underneath the cerebral hemispheres. Although its name translates as ‘little brain' in Latin, the cerebellum contains more neurons than all other regions of the mammalian brain combined. Most cerebellar neurons are granule cells which, although numerous, are simple neurons with an average of only four excitatory inputs, from axons called mossy fibers. These inputs are diverse in nature, originating from virtually every sensory system and from command centers at multiple levels of the motor hierarchy. However, it is unclear whether individual granule cells receive inputs from only a single sensory source or can instead mix modalities. This distinction has important implications for the functional capabilities of the cerebellum. Now, Huang et al. have addressed this question by mapping, at extremely high resolution, the projections of two pathways onto individual granule cells—one carrying sensory feedback from the upper body (the proprioceptive stream), and another carrying motor-related information (the pontine stream). Using a combination of genetic and viral techniques to label the pathways, Huang and co-workers identified regions where the two types of fiber terminated in close proximity. They then showed that around 40% of proprioceptive granule cells formed junctions, or synapses, with two (or more) fibers carrying different types of input. These cells were not uniformly distributed throughout the cerebellum but tended to occur in ‘hotspots’. Lastly, Huang et al. examined the type of information conveyed by the sensory and motor-related input streams whenever they contacted a single granule cell. They confirmed that when the sensory input consisted of feedback from the upper body, the motor input consisted of copies of motor commands related to the same body region. Because it is thought that the cerebellum converts sensory information into representations of the body's movements, directing motor commands to these same circuits may allow the cerebellum to predict the consequences of a planned movement prior to, or without, the actual movement occurring. The work of Huang et al. provides evidence to support the previously controversial idea that granule cells in the mammalian cerebellum receive both sensory and motor-related inputs. The labeling technique that they used could also be deployed to study the inputs to the cerebellum in greater detail, which should yield new insights into the functioning of this part of the brain.
212 citations
01 Jan 2013
TL;DR: Evidence suggesting that maturation of interneuron cell-type-specific firing properties and ion channel expression arise from the interplay between cell-autonomous gene regulatory networks as well as cell-extrinsic factors, such as brain-derived neurotrophic factor (BDNF) signaling and neural activity is reviewed.
Abstract: GABAergic interneurons display diverse cellular morphology, connectivity, and intrinsic membrane properties, allowing different interneuron subtypes to exert unique effects on neural activity. Although cell fates may be specified much earlier, distinctive firing types emerge after migration from the ganglionic eminences as interneurons integrate into forebrain circuits. We review evidence suggesting that maturation of interneuron cell-type-specific firing properties and ion channel expression arise from the interplay between cell-autonomous gene regulatory networks as well as cell-extrinsic factors, such as brain-derived neurotrophic factor (BDNF) signaling and neural activity.
1 citations