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Möbius-strip-like columnar functional connections are revealed in somato-sensory receptive field centroids.

Wright JJ, Bourke PD, Favorov OV - Front Neuroanat (2014)

Bottom Line: Locations of the field centroids indicated the presence of a functional system in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Möbius-strip-like patterns of synaptic connections.Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order.Since the theory of embryonic synaptic self-organization used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychological Medicine, Faculty of Medicine, The University of Auckland Auckland, New Zealand.

ABSTRACT
Receptive fields of neurons in the forelimb region of areas 3b and 1 of primary somatosensory cortex, in cats and monkeys, were mapped using extracellular recordings obtained sequentially from nearly radial penetrations. Locations of the field centroids indicated the presence of a functional system in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Möbius-strip-like patterns of synaptic connections. Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order. Since the theory of embryonic synaptic self-organization used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

No MeSH data available.


(A) Nested RFs in the distal paw. (Type I -single macrocolumn). Left: Superposition of all RFs in a dataset. Color spectrum represents density of overlap of RFs; red most dense. Right: Separate RF nests. Retaining the same color coding in the complete dataset, these are arranged in order of the number of RFs in each nest—15, 14, 4, and 3, respectively. (B) RF nest in the forearm. (Types II—three macrocolumns). All RFs surround a single centroid.
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Figure 13: (A) Nested RFs in the distal paw. (Type I -single macrocolumn). Left: Superposition of all RFs in a dataset. Color spectrum represents density of overlap of RFs; red most dense. Right: Separate RF nests. Retaining the same color coding in the complete dataset, these are arranged in order of the number of RFs in each nest—15, 14, 4, and 3, respectively. (B) RF nest in the forearm. (Types II—three macrocolumns). All RFs surround a single centroid.

Mentions: Figures 13A,B show two cases at these extremes.


Möbius-strip-like columnar functional connections are revealed in somato-sensory receptive field centroids.

Wright JJ, Bourke PD, Favorov OV - Front Neuroanat (2014)

(A) Nested RFs in the distal paw. (Type I -single macrocolumn). Left: Superposition of all RFs in a dataset. Color spectrum represents density of overlap of RFs; red most dense. Right: Separate RF nests. Retaining the same color coding in the complete dataset, these are arranged in order of the number of RFs in each nest—15, 14, 4, and 3, respectively. (B) RF nest in the forearm. (Types II—three macrocolumns). All RFs surround a single centroid.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4215792&req=5

Figure 13: (A) Nested RFs in the distal paw. (Type I -single macrocolumn). Left: Superposition of all RFs in a dataset. Color spectrum represents density of overlap of RFs; red most dense. Right: Separate RF nests. Retaining the same color coding in the complete dataset, these are arranged in order of the number of RFs in each nest—15, 14, 4, and 3, respectively. (B) RF nest in the forearm. (Types II—three macrocolumns). All RFs surround a single centroid.
Mentions: Figures 13A,B show two cases at these extremes.

Bottom Line: Locations of the field centroids indicated the presence of a functional system in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Möbius-strip-like patterns of synaptic connections.Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order.Since the theory of embryonic synaptic self-organization used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychological Medicine, Faculty of Medicine, The University of Auckland Auckland, New Zealand.

ABSTRACT
Receptive fields of neurons in the forelimb region of areas 3b and 1 of primary somatosensory cortex, in cats and monkeys, were mapped using extracellular recordings obtained sequentially from nearly radial penetrations. Locations of the field centroids indicated the presence of a functional system in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Möbius-strip-like patterns of synaptic connections. Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order. Since the theory of embryonic synaptic self-organization used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

No MeSH data available.