Editing Barrel cortex (section)

{{short description|Region of the somatosensory cortex in some rodents and other species}}
{{technical|date=January 2016}}
{{Infobox brain
| Name       = Barrel cortex
}}
[[File:RatBarrelFieldCOstain.jpg|thumb|200px|Pictomicrograph shows the barrel field in layer IV of the rat somatosensory cortex. Each barrel receives input from one whisker. The tissue in the image has been stained with cytochrome oxidase and is 50μm thick.]]

The '''barrel cortex''' is a region of the [[somatosensory cortex]] that is identifiable in some species of [[rodent]]s and species of at least two other [[order (biology)|orders]]<ref>[[#refWoolsey1975|Woolsey et al., 1975]]</ref> and contains the barrel field. The 'barrels' of the barrel field are regions within [[Cerebral cortex#Layer IV|cortical layer IV]] that are visibly darker when stained to reveal the presence of [[cytochrome c oxidase]] and are separated from each other by lighter areas called septa. These dark-staining regions are a major target for somatosensory inputs from the [[thalamus]], and each barrel corresponds to a region of the body. Due to this distinctive cellular structure, organisation, and functional significance, the barrel cortex is a useful tool to understand cortical processing and has played an important role in neuroscience.<ref name="Fox, 2008">[[#refFoxBook|Fox, 2008]]</ref> The majority of what is known about corticothalamic processing comes from studying the barrel cortex, and researchers have intensively studied the barrel cortex as a model of [[neocortical column]].

The most distinctive aspect of the barrel field are the whisker barrels. These structures were first discovered by Woolsey and Van der Loos in 1970.<ref>[[#refWoolsey1970|Woolsey & Van der Loos, 1970]]</ref> Staining in the whisker barrels is more distinct than that in other areas of the somatosensory cortex. Recognizing that the array was similar to that of the [[vibrissae]] (whiskers) on the mystacial pad (region where whiskers grow from) of certain mammals, they hypothesized that the barrels were the "cortical correlates of the mystacial vibrissae" and that "one barrel represents one vibrissa". Whereas small non-whisker areas of barrel cortex correspond to large and sometimes overlapping areas of the body, each much larger whisker barrel corresponds to a single whisker. As a result, the whisker barrels are the focus of the majority of barrel cortex research, and 'barrel cortex' is often used to refer primarily to the whisker barrels. Consequently, much of this article focuses on rodent whisker barrel cortex.