Limits...
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 “vertical” penetration of cortex in a cat. Top Left: Experimental data—centroids of RFs, red and blue colors indicate hypothetical position within Möbius organization of macrocolumn. Top Right: RF centroids on cat forelimb outline. Bottom Left: Best fit of theoretical model to experimental data. Background green line is outline of experimental plot. Bottom Right: Theoretical construction of passage of recording electrode, on plane view of cortical surface.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4215792&req=5

Figure 7: A “vertical” penetration of cortex in a cat. Top Left: Experimental data—centroids of RFs, red and blue colors indicate hypothetical position within Möbius organization of macrocolumn. Top Right: RF centroids on cat forelimb outline. Bottom Left: Best fit of theoretical model to experimental data. Background green line is outline of experimental plot. Bottom Right: Theoretical construction of passage of recording electrode, on plane view of cortical surface.

Mentions: Figures 7–12 show representative results. Complete analyses of all datasets are supplementary to this paper, and are commented on further at the end of this section. An example from each of cat and monkey is shown, for each of the three types on the continuum of possibilities forecast in Figures 3–5.


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

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

A “vertical” penetration of cortex in a cat. Top Left: Experimental data—centroids of RFs, red and blue colors indicate hypothetical position within Möbius organization of macrocolumn. Top Right: RF centroids on cat forelimb outline. Bottom Left: Best fit of theoretical model to experimental data. Background green line is outline of experimental plot. Bottom Right: Theoretical construction of passage of recording electrode, on plane view of cortical surface.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 7: A “vertical” penetration of cortex in a cat. Top Left: Experimental data—centroids of RFs, red and blue colors indicate hypothetical position within Möbius organization of macrocolumn. Top Right: RF centroids on cat forelimb outline. Bottom Left: Best fit of theoretical model to experimental data. Background green line is outline of experimental plot. Bottom Right: Theoretical construction of passage of recording electrode, on plane view of cortical surface.
Mentions: Figures 7–12 show representative results. Complete analyses of all datasets are supplementary to this paper, and are commented on further at the end of this section. An example from each of cat and monkey is shown, for each of the three types on the continuum of possibilities forecast in Figures 3–5.

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.