Talk:Pyramidal tracts

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What is the evolutionary advantage of the pyramidal decussation - indeed, neuronal decussations in general (e.g. the optic chiasm)? What pressures would cause such a system to evolve? (To me, the entire 'split-brain' system seems to be prima facie inefficient.) Can anyone enlighten me? -- FirstPrinciples 15:28, Aug 15, 2004 (UTC)   
:Your question suggests that you believe efficiency is a hallmark of evolution, which of course it is not! Systems evolve by a variety of fortuitous outcomes, false starts, and contingent events, and in response to changing environments: efficiency would imply design, not evolution. - Nunh-huh 05:42, 16 Aug 2004 (UTC)
replies: text: Very simple answer. The split brain allows specialization of the hemispheres rather than simple duplication. The advantage of a "spare brain" (like a spare kidney) is less than the advantage of "2 brains" that to some extent do different things. (And yes, a complete split would be bad, and yes some symmetrical motor functions are retained). Alteripse 16:03, 15 Aug 2004 (UTC)
replies: text: However, it is possible for a person to function with damage to the corpus callosum (with various effects). There is normally considerable intercommunication between hemispheres due to their high degrees of specialization. A split brain allows complex analysis according to opposite (but synergistic) paradigms simultaneously without interference (parallel processing). In this way, a complex result incorporating both paradigms is obtained without loss of efficiency for either. --Eequor 16:41, 15 Aug 2004 (UTC)

text: The decussation may be a survival trait. Crossover of motor function may ensure that a damaged part of the body is less likely to be associated with similar damage to the region of the brain controlling it, as they are on opposite sides. --Eequor 16:41, 15 Aug 2004 (UTC)

text: I'm pretty sure the Corticospinal tract article refers only to the human nervous system. In other animals, even other primates, the basic layout of the brain can be significantly different. (Side note: in my experience there are several articles out there about general anatomy that are implicitly about human anatomy. The penis wiki comes to mind, which deals with the human penis as if it is "the" exemplar of all penises in all species. We should be careful to avoid the trap of anthropocentrism.) -- FirstPrinciples 01:53, 16 Aug 2004 (UTC)
thread_title:  Evolutionary advantage of the pyramidal decussation 

message: Is it intentiional to omit cranial nerves IX and X (glossopharyngeal and vagus) from the Lower Motor Neurone section? It seems strange since each of these nerves carry both sensory and motor neurones.  —Preceding unsigned comment added by Miniyazz (talk • contribs) 02:08, 3 December 2007 (UTC)
thread_title:  CN omission? 

message: 2nd image doesn't help much. Try subtitute it with this image http://upload.wikimedia.org/wikipedia/commons/b/b2/Spinal_cord_tracts_-_English.svg  — Preceding unsigned comment added by 203.82.87.119 (talk) 02:54, 6 May 2012 (UTC)
replies: text: Mikael Häggström (talk) 18:33, 20 June 2012 (UTC)
thread_title:  2nd image 

message: I heard somewhere that this is the name of a housing development outside Cairo  — Preceding unsigned comment added by 76.111.5.228 (talk) 23:59, 23 August 2012 (UTC)
thread_title:  Should we have a disambiguation page? 

message: Would it be possible to mention that the Pyramidal tracts have a "popular culture" reference in the 1985 Movie, National Lampoon's European Vacation? Its one of the questions in the game show in the opening scene?  72.74.176.144 (talk) 15:35, 12 July 2013 (UTC)
thread_title:  Popular Culture  

message: The history of this subject is documented in this source:
* .
There is very likely to be a more recent source, but this may act as a useful adjunct to research. --LT910001 (talk) 00:10, 8 June 2014 (UTC)
thread_title:  History 

message: I suggest the use of Gray764.png as the cover image for this article. Inputs requested. DiptanshuTalk 15:46, 7 July 2014 (UTC)
thread_title:  Image for article