3.1 Overview of the thalamus.pdf

《3.1 Overview of the thalamus.pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、3.1Overviewofthethalamus2015年5月2日Introduction1.Embryologicaloriginofthethalamusthethalamusisamajorpartofthediencephalon,whichisderivedfromtheprosencephalon(seeFigure22.3andA242)1.thedorsalandposteriorpartofthediencephalonbecomesthethalamus2.theventralandanteriorpartbecomesthehypothalamus3.thu

2、s,thethalamusisacomponentoftheforebrain分区02.大脑科学的第1页2.AnatomicallocalizationofthethalamusA.withrespecttothewholebrain:thethalamusisnearthecenteroftheforebrain(seeFigureA14C;AppendixBoxA(FigureA))B.relativetotheinternalcapsule:thethalamusismedialtotheposteriorlimboftheinternalcapsule(seeFigure

3、A14B)C.relativetothelateralventricle:thethalamusisthefloorofthebodyofthelateralventricle(seeFigureA14C)3.RoleofthethalamusinbrainfunctionA.generalorganization(seeAppendixBoxA(FigureA))1.comprisedofalargenumberofdistinctnuclei(circumscribedclustersofneurons)thatareboundedbya“Y”-shapedbundleofa

4、xons2.eachnucleussendsandreceivesprojectionsforadifferentregionofthecerebralcortex:a.anteriorgroup(inthecrookofthe“Y”)projectstocingulategyrusb.medialgroupprojectstotheanteriorfrontallobeinfrontofthemotorcortex(i.e.,theprefrontalcortex),theinsulaandthemedialtemporallobec.lateralgroupprojectst

5、odifferentregionsoftheremainingsensoryandmotorregionsofthecerebralcortexineachlobed.additionally,therearesmallernucleiwithinthefiberbundlesthatmakeupthe“Y”;theseintralaminarnucleiprojectdiffuselythroughoutthecerebralcortex分区02.大脑科学的第2页B.principalfunctions(seeAppendixBoxA(FigureB))1.relayinfor

6、mation,ina“feed-forward”fashion,tothecerebralcortexa.sourcesofinputtospecificthalamicrelaynucleii.forsomaticsensation,fromthespinalcordandbrainstemii.forauditionandvestibularsensation,fromthebrainstemiii.forvision,fromthesensoryperiphery(retina)iv.forthemodulationofmovement,fromthebasalgangli

7、aandthecerebellumb.outputsfromspecificthalamicrelaynucleitothecerebralcortex;theseoutputstothecerebralcortexterminatedenselyinlayer4thusdefiningunimodal,“primary”corticalareasi.forsomaticsensation,tothepostcentralgyrusii.foraudition,tothesupe