A theory of cortical map formation in the visual brain

The cerebral cortex receives multiple afferents from the thalamus that segregate by stimulus modality forming cortical maps for each sense. In vision, the primary visual cortex also maps the multiple dimensions of the stimulus in patterns that vary across species for reasons unknown. Here we introduce a general theory of cortical map formation, which proposes that map diversity emerges from variations in sampling density of sensory space across species. In the theory, increasing afferent sampling density enlarges the cortical domains representing the same visual point allowing the segregation of afferents and cortical targets by additional stimulus dimensions. We illustrate the theory with a computational model that accurately replicates the maps of different species through afferent segregation followed by thalamocortical convergence pruned by visual experience. Because thalamocortical pathways use similar mechanisms for axon sorting and pruning, the theory may extend to other sensory areas of the mammalian brain.

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Effects of visual experience on development of T-type Ca2+ channels in rat visual cortex

Neuroscience Research ◽

10.1016/s0168-0102(00)81170-0 ◽

2000 ◽

Vol 38 ◽

pp. S54

Author(s):

Y Yoshimura

Keyword(s):

Visual Cortex ◽

Visual Experience ◽

Ca2 Channels

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Faculty Opinions recommendation of The development of direction selectivity in ferret visual cortex requires early visual experience.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1009281.373151 ◽

2006 ◽

Author(s):

Gina Turrigiano

Keyword(s):

Visual Cortex ◽

Visual Experience ◽

Direction Selectivity

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BMP signaling alters aquaporin-4 expression in the mouse cerebral cortex

Scientific Reports ◽

10.1038/s41598-021-89997-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kazuya Morita ◽

Naoyuki Matsumoto ◽

Kengo Saito ◽

Toshihide Hamabe-Horiike ◽

Keishi Mizuguchi ◽

...

Keyword(s):

Cerebral Cortex ◽

Molecular Mechanisms ◽

Water Movement ◽

Water Channel ◽

Bmp Signaling ◽

Aquaporin 4 ◽

Mammalian Brain ◽

Physiological Conditions ◽

Pathological Conditions ◽

Mouse Cerebral Cortex

AbstractAquaporin-4 (AQP4) is a predominant water channel expressed in astrocytes in the mammalian brain. AQP4 is crucial for the regulation of homeostatic water movement across the blood–brain barrier (BBB). Although the molecular mechanisms regulating AQP4 levels in the cerebral cortex under pathological conditions have been intensively investigated, those under normal physiological conditions are not fully understood. Here we demonstrate that AQP4 is selectively expressed in astrocytes in the mouse cerebral cortex during development. BMP signaling was preferentially activated in AQP4-positive astrocytes. Furthermore, activation of BMP signaling by in utero electroporation markedly increased AQP4 levels in the cerebral cortex, and inhibition of BMP signaling strongly suppressed them. These results indicate that BMP signaling alters AQP4 levels in the mouse cerebral cortex during development.

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Disabled-1 acts downstream of Reelin in a signaling pathway that controls laminar organization in the mammalian brain

Development ◽

10.1242/dev.125.18.3719 ◽

1998 ◽

Vol 125 (18) ◽

pp. 3719-3729 ◽

Cited By ~ 2

Author(s):

D.S. Rice ◽

M. Sheldon ◽

G. D'Arcangelo ◽

K. Nakajima ◽

D. Goldowitz ◽

...

Keyword(s):

Cerebral Cortex ◽

Signaling Pathway ◽

Developmental Process ◽

Cortical Plate ◽

Mammalian Brain ◽

Granule Neurons ◽

Adapter Protein ◽

Cell Position ◽

Neuronal Precursors ◽

Retzius Cells

Mutation of either reelin (Reln) or disabled-1 (Dab1) results in widespread abnormalities in laminar structures throughout the brain and ataxia in reeler and scrambler mice. Both exhibit the same neuroanatomical defects, including cerebellar hypoplasia with Purkinje cell ectopia and disruption of neuronal layers in the cerebral cortex and hippocampus. Despite these phenotypic similarities, Reln and Dab1 have distinct molecular properties. Reln is a large extracellular protein secreted by Cajal-Retzius cells in the forebrain and by granule neurons in the cerebellum. In contrast, Dab1 is a cytoplasmic protein which has properties of an adapter protein that functions in phosphorylation-dependent intracellular signal transduction. Here, we show that Dab1 participates in the same developmental process as Reln. In scrambler mice, neuronal precursors are unable to invade the preplate of the cerebral cortex and consequently, they do not align within the cortical plate. During development, cells expressing Dab1 are located next to those secreting Reln at critical stages of formation of the cerebral cortex, cerebellum and hippocampus, before the first abnormalities in cell position become apparent in either reeler or scrambler. In reeler, the major populations of displaced neurons contain elevated levels of Dab1 protein, although they express normal levels of Dab1 mRNA. This suggests that Dab1 accumulates in the absence of a Reln-evoked signal. Taken together, these results indicate that Dab1 functions downstream of Reln in a signaling pathway that controls cell positioning in the developing brain.

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The role of early visual experience in the development of spatial‐frequency preference in the primary visual cortex

The Journal of Physiology ◽

10.1113/jp281463 ◽

2021 ◽

Author(s):

Nana Nishio ◽

Kenji Hayashi ◽

Ayako Wendy Ishikawa ◽

Yumiko Yoshimura

Keyword(s):

Visual Cortex ◽

Spatial Frequency ◽

Primary Visual Cortex ◽

Visual Experience

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Neuronal Distribution Across the Cerebral Cortex of the Marmoset Monkey (Callithrix jacchus)

Cerebral Cortex ◽

10.1093/cercor/bhy263 ◽

2018 ◽

Vol 29 (9) ◽

pp. 3836-3863 ◽

Cited By ~ 10

Author(s):

Nafiseh Atapour ◽

Piotr Majka ◽

Ianina H Wolkowicz ◽

Daria Malamanova ◽

Katrina H Worthy ◽

...

Keyword(s):

Cerebral Cortex ◽

Visual Cortex ◽

Complex Interaction ◽

Anterior Cingulate ◽

Functional Requirements ◽

Anterior Cortex ◽

Neuronal Density ◽

Marmoset Monkey ◽

Posterior Parietal ◽

Neuronal Distribution

Abstract Using stereological analysis of NeuN-stained sections, we investigated neuronal density and number of neurons per column throughout the marmoset cortex. Estimates of mean neuronal density encompassed a greater than 3-fold range, from >150 000 neurons/mm3 in the primary visual cortex to ~50 000 neurons/mm3 in the piriform complex. There was a trend for density to decrease from posterior to anterior cortex, but also local gradients, which resulted in a complex pattern; for example, in frontal, auditory, and somatosensory cortex neuronal density tended to increase towards anterior areas. Anterior cingulate, motor, premotor, insular, and ventral temporal areas were characterized by relatively low neuronal densities. Analysis across the depth of the cortex revealed greater laminar variation of neuronal density in occipital, parietal, and inferior temporal areas, in comparison with other regions. Moreover, differences between areas were more pronounced in the supragranular layers than in infragranular layers. Calculations of the number of neurons per unit column revealed a pattern that was distinct from that of neuronal density, including local peaks in the posterior parietal, superior temporal, precuneate, frontopolar, and temporopolar regions. These results suggest that neuronal distribution in adult cortex result from a complex interaction of developmental/ evolutionary determinants and functional requirements.

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The Expression and Distributions of ANP32A in the Developing Brain

BioMed Research International ◽

10.1155/2015/207347 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Shanshan Wang ◽

Yunliang Wang ◽

Qingshan Lu ◽

Xinshan Liu ◽

Fuyu Wang ◽

...

Keyword(s):

Cerebral Cortex ◽

Fetal Brain ◽

Tissue Expression ◽

Developing Brain ◽

Adult Brain ◽

Mammalian Brain ◽

Dependent Manner ◽

Growing Up ◽

Embryonic Mouse ◽

And Function

Acidic (leucine-rich) nuclear phosphoprotein 32 family, member A (ANP32A), has multiple functions involved in neuritogenesis, transcriptional regulation, and apoptosis. However, whether ANP32A has an effect on the mammalian developing brain is still in question. In this study, it was shown that brain was the organ that expressed the most abundant ANP32A by human multiple tissue expression (MTE) array. The distribution of ANP32A in the different adult brain areas was diverse dramatically, with high expression in cerebellum, temporal lobe, and cerebral cortex and with low expression in pons, medulla oblongata, and spinal cord. The expression of ANP32A was higher in the adult brain than in the fetal brain of not only humans but also mice in a time-dependent manner. ANP32A signals were dispersed accordantly in embryonic mouse brain. However, ANP32A was abundant in the granular layer of the cerebellum and the cerebral cortex when the mice were growing up, as well as in the Purkinje cells of the cerebellum. The variation of expression levels and distribution of ANP32A in the developing brain would imply that ANP32A may play an important role in mammalian brain development, especially in the differentiation and function of neurons in the cerebellum and the cerebral cortex.

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Mechanisms of L-Triiodothyronine-Induced Inhibition of Synaptosomal Na+-K+-ATPase Activity in Young Adult Rat Brain Cerebral Cortex

Journal of Thyroid Research ◽

10.1155/2013/457953 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Pradip K. Sarkar ◽

Avijit Biswas ◽

Arun K. Ray ◽

Joseph V. Martin

Keyword(s):

Cerebral Cortex ◽

Atpase Activity ◽

Adrenergic Receptor ◽

Receptor Activation ◽

Mammalian Brain ◽

Neuronal Membrane ◽

Dependent Manner ◽

Adrenergic Agonist ◽

Adult Rat ◽

Dose Dependent

The role of thyroid hormones (TH) in the normal functioning of adult mammalian brain is unclear. Our studies have identified synaptosomal Na+-K+-ATPase as a TH-responsive physiological parameter in adult rat cerebral cortex. L-triiodothyronine (T3) and L-thyroxine (T4) both inhibited Na+-K+-ATPase activity (but not Mg2+-ATPase activity) in similar dose-dependent fashions, while other metabolites of TH were less effective. Although both T3and theβ-adrenergic agonist isoproterenol inhibited Na+-K+-ATPase activity in cerebrocortical synaptosomes in similar ways, theβ-adrenergic receptor blocker propranolol did not counteract the effect of T3. Instead, propranolol further inhibited Na+-K+-ATPase activity in a dose-dependent manner, suggesting that the effect of T3on synaptosomal Na+-K+-ATPase activity was independent ofβ-adrenergic receptor activation. The effect of T3on synaptosomal Na+-K+-ATPase activity was inhibited by theα2-adrenergic agonist clonidine and by glutamate. Notably, both clonidine and glutamate activateGi-proteins of the membrane second messenger system, suggesting a potential mechanism for the inhibition of the effects of TH. In this paper, we provide support for a nongenomic mechanism of action of TH in a neuronal membrane-related energy-linked process for signal transduction in the adult condition.

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Simulated Optic Flow and Extrastriate Cortex. I. Optic Flow Versus Texture

Journal of Neurophysiology ◽

10.1152/jn.1997.77.2.554 ◽

1997 ◽

Vol 77 (2) ◽

pp. 554-561 ◽

Cited By ~ 26

Author(s):

Jong-Nam Kim ◽

Kathleen Mulligan ◽

Helen Sherk

Keyword(s):

Visual Cortex ◽

Visual Field ◽

Optic Flow ◽

Visual Experience ◽

Extrastriate Cortex ◽

Gray Level ◽

Visual Guidance ◽

Forward Motion ◽

Cell Responses ◽

Single Origin

Kim, Jong-Nam, Kathleen Mulligan, and Helen Sherk. Simulated optic flow and extrastriate cortex. I. Optic flow versus texture. J. Neurophysiol. 77: 554–561, 1997. A locomoting observer sees a very different visual scene than an observer at rest: images throughout the visual field accelerate and expand, and they follow approximately radial outward paths from a single origin. This so-called optic flow field is presumably used for visual guidance, and it has been suggested that particular areas of visual cortex are specialized for the analysis of optic flow. In the cat, the lateral suprasylvian visual area (LS) is a likely candidate. To test the hypothesis that LS is specialized for analysis of optic flow fields, we recorded cell responses to optic flow displays. Stimulus movies simulated the experience of a cat trotting slowly across an endless plain covered with small balls. In different simulations we varied the size of balls, their organization (randomly or regularly dispersed), and their color (all one gray level, or multiple shades of gray). For each optic flow movie, a “texture” movie composed of the same elements but lacking optic flow cues was tested. In anesthetized cats, >500 neurons in LS were studied with a variety of movies. Most (70%) of 454 visually responsive cells responded to optic flow movies. Visually responsive cells generally preferred optic flow to texture movies (69% of those responsive to any movie). The direction in which a movie was shown (forward or reverse) was also an important factor. Most cells (68%) strongly preferred forward motion, which corresponded to visual experience during locomotion.

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