Abstract
Neocortical areas are believed to be organized into vertical modules, the cortical columns, and the horizontal layers 1–6. In the somatosensory barrel cortex these columns are defined by the readily discernible barrel structure in layer 4. Information processing in the neocortex occurs along vertical and horizontal axes, thereby linking individual barrel-related columns via axons running through the different cortical layers of the barrel cortex. Long-range signaling occurs within the neocortical layers but also through axons projecting through the white matter to other neocortical areas and subcortical brain regions. Because of the ease of identification of barrel-related columns, the rodent barrel cortex has become a prototypical system to study the interactions between different neuronal connections within a sensory cortical area and between this area and other cortical as well subcortical regions. Such interactions will be discussed specifically for the feed-forward and feedback loops between the somatosensory and the somatomotor cortices as well as the different thalamic nuclei. In addition, recent advances concerning the morphological characteristics of excitatory neurons and their impact on the synaptic connectivity patterns and signaling properties of neuronal microcircuits in the whisker-related somatosensory cortex will be reviewed. In this context, their relationship between the structural properties of barrel-related columns and their function as a module in vertical synaptic signaling in the whisker-related cortical areas will be discussed.
Highlights
In the 1950s, Vernon Mountcastle (Mountcastle, 1957, 1997, 2003) introduced the expression “cortical column” for the concept of vertical information processing in the somatosensory cortex, an idea that was later adopted by David Hubel and Torsten Wiesel (Hubel and Wiesel, 1959, 1963) for the visual cortex
Afferents arising from the head of the ventroposterior medial (VPM) barreloid [i.e., those in the lemniscal (2) branch] innervate exclusively neurons located in the layer 4 (L4) “septa” and have multi-whisker www.frontiersin.org
Many interactions between cortical output neurons and neurons in other cortical and subcortical target regions show somatotopic arrangements suggesting a specific interaction between cortical columns in different cortical areas, particular the M1 and S2 cortex
Summary
Reviewed by: Idan Segev, The Hebrew University of Jerusalem, Israel Heiko J. Because of the ease of identification of barrel-related columns, the rodent barrel cortex has become a prototypical system to study the interactions between different neuronal connections within a sensory cortical area and between this area and other cortical as well subcortical regions Such interactions will be discussed for the feed-forward and feedback loops between the somatosensory and the somatomotor cortices as well as the different thalamic nuclei. Recent advances concerning the morphological characteristics of excitatory neurons and their impact on the synaptic connectivity patterns and signaling properties of neuronal microcircuits in the whisker-related somatosensory cortex will be reviewed. In this context, their relationship between the structural properties of barrel-related columns and their function as a module in vertical synaptic signaling in the whisker-related cortical areas will be discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
