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Showing papers by "Arnold B. Scheibel published in 1967"


Journal ArticleDOI
TL;DR: The changes in spine morphology representing the response of visual cortex to complete lack of visual stimulation underline the sensitivity of immature cortex to the external milieu.

242 citations


Journal ArticleDOI
TL;DR: The study underlines the sensitivity of postsynaptic components to changes in level of presynaptic function and focuses attention upon the dendrite spine as an accurate index of presyaptic geometry, thereby providing a more effective measure of terminal axonal patterns throughout the nervous system.

183 citations


Journal ArticleDOI
TL;DR: The data indicate that neurons with extra‐cortically projecting axons (long axons) invariably possess spine‐rich dendrites forming domains with remarkably regular horizontal parameters (i.e. modular domains), and cells with axons limited to intra-cortical paths are characterized by spine‐poor or spine‐free dendrite forming domains which are highly variable in size and shape.
Abstract: Previous attempts at classification of cortical neurons have been based on a number of anatomical characteristics, some of doubtful physiological significance. In seeking a functionally more relevant scheme, we have based our classification on three neural attributes; (a) size and shape of the dendritic domain, (b) presence or absence of dendritic spines, and (c) intra or extra-cortical trajectory of the axon, as revealed in Golgi stained material. Our data indicate that neurons with extra-cortically projecting axons (long axons) invariably possess spine-rich dendrites forming domains with remarkably regular horizontal parameters (i.e. modular domains). Cells with axons limited to intra-cortical paths (short axons) are characterized by spine-poor or spine-free dendrites forming domains which are highly variable in size and shape. These two categories appear dependant on structural characteristics related both to input and output functions of cortical neurons, and are called Class I and II, respectively. The significance of synaptic arrangements along horizontal and vertical components of Class I dendritic modules are compared with those for Class II cells, and possible relationships between dendritic structure and temporo-spatial activity patterns are considered.

152 citations



Journal ArticleDOI
TL;DR: The extent of integrity of the isolated glial cells should enable more extended studies to be conducted using larger quantities ofglial cells of comparable purity than have hitherto been available.

50 citations


Journal ArticleDOI
01 Feb 1967-Nature
TL;DR: An attempt to couple a sensory artefact to brain, which uses a biologically destructive stimulus as an input source and which feeds a neural centre, the output of which has been empirically determined to be appropriate to such an input.
Abstract: THE construction of artificial analogues of sensory receptors has recently become practicable. There are a number of electronic and electro-mechanical techniques for converting external stimuli into discharge trains similar to those initiated by receptors in the afferent peripheral nerves. It is more difficult, however, to devise satisfactory ways of coupling this type of mechanism to the brain so that the sensory influx provides information resulting in the evolution of a realistic motor programme. Although progress has been made in unravelling the “sensory coding” along some receptor channels1,2, much remains to be learned about the nature of sensory signals, their spatio-temporal organization and their interaction patterns. This communication briefly describes an attempt to couple a sensory artefact to brain, which uses a biologically destructive stimulus as an input source and which feeds a neural centre, the output of which has been empirically determined to be appropriate to such an input.

3 citations