Geniculocortical Input Drives Genetic Distinctions Between Primary and Higher-Order Visual Areas

By Shen-Ju Chou, Z. Babot, Axel Leingärtner, M. Studer, Y. Nakagawa, D. O'Leary. 2013

139 citations recorded by the source corpus.

Dividing the Brain The cerebral cortex of the brain is organized into primary cortical areas, which receive direct inputs from the thalamus, and higher-order cortical areas, which in turn receive inputs from one or more primary cortical areas. Chou et al. (p. 1239) investigated the mechanisms underlying the specification of higher-order cortical areas. Input from the dorsal lateral geniculate nucleus into the primary visual area (V1) is required to drive the genetic and functional differentiation of a large visual cortical field into primary and higher-order visual areas. Thalamocortical axon input acts on a large visual cortical field. The afferents from the dorsal lateral geniculate are necessary to further refine the cortex into subareas that distinguish V1 from higher processing areas. In the relatively simple model that emerges from these findings, sensory input is essential to distinguish primary and higher-order cortical areas. Neural activity in the developing visual system dictates differential gene expression in the primary and higher-order areas. Studies of area patterning of the neocortex have focused on primary areas, concluding that the primary visual area, V1, is specified by transcription factors (TFs) expressed by progenitors. Mechanisms that determine higher-order visual areas (VHO) and distinguish them from V1 are unknown. We demonstrated a requirement for thalamocortical axon (TCA) input by genetically deleting geniculocortical TCAs and showed that they drive differentiation of patterned gene expression that distinguishes V1 and VHO. Our findings suggest a multistage process for area patterning: TFs expressed by progenitors specify an occipital visual cortical field that differentiates into V1 and VHO; this latter phase requires geniculocortical TCA input to the nascent V1 that determines genetic distinctions between V1 and VHO for all layers and ultimately determines their area-specific functional properties.

Subfields: Cellular and Molecular Neuroscience, Cognitive Neuroscience

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Cellular and Molecular Neuroscience

Bradley L. Schlaggar

In Cognitive Neuroscience

Citations in the corpus

Neural plasticity across the lifespan (2016, background): “More recently it has been found that although molecular gradients specify a broad occipital visual field, that visual stimulation must be targeted to what will become the primary visual area to cause the primary visual area to correctly differentiate from the rest of the occipital visual field (and ”
The Cellular and Molecular Landscapes of the Developing Human Central Nervous System (2016, unknown): “, 2015), and (2) their position in the tangential plane, corresponding to their particular cortical areal identity, which mouse studies show is governed by graded expression of transcription factors during early embryonic development, followed by extrinsic signaling from thalamic axonal inputs (Chou”