White Matter vs Grey Matter
Ob qho teeb meem dawb thiab grey teeb meem yog cov ntsiab lus uas cuam tshuam nrog lub hlwb ntawm lub hlwb. Ib ntu ntawm lub paj hlwb yuav qhia cov hlwb hauv lawv cov xim, thiab lawv muaj npe li dawb thiab grey teeb meem. Txawm li cas los xij, ob hom kab mob hlwb ua dawb thiab grey tom qab dipped nyob rau hauv preservatives raws li cov xim nyob txawv me ntsis nrog rau cov ntshav. Grey thiab dawb teeb meem yog ob lub ntsiab ntawm lub hlwb hlwb thiab cov haujlwm ntawm cov no txawv ntawm ib leeg. Feem ntau, cov txheej txheem ua tiav los ntawm cov teeb meem grey tau dhau los ntawm cov teeb meem dawb hauv lub hlwb.
Nyob zoo
Cov teeb meem Dawb yog ib qho ntawm ob lub ntsiab lus ntawm lub hlwb uas sib koom ua ke sib txawv ntawm lub hlwb. Nws tau hais tias cov teeb meem dawb ntawm lub hlwb yog sib npaug rau cov cables ntawm lub computer network. Txawm tias cov ntaub so ntswg hu ua dawb, cov xim nyob yog pinkish dawb vim muaj ntshav. Cov tshuaj tiv thaiv ib txwm muaj, formaldehyde, ua rau cov teeb meem dawb ua kom dawb. Txawm hais tias nws tau hais ntawm no tias cov teeb meem dawb muaj nyob hauv lub hlwb, tseem muaj cov ntaub so ntswg dawb nyob rau lwm qhov ntawm lub cev cuam tshuam nrog cov hlab ntsha xws li qaum qaum, ntshav…etc.
Cov teeb meem Dawb muaj ob lub hlwb glial thiab ntev axons uas feem ntau myelinated. Cov dendrites tsis muaj nyob rau hauv lub paj hlwb thiab txha caj qaum dawb teeb meem, tab sis tsis muaj lub cev neuronal. Feem ntau (60%) ntawm lub hlwb yog tsim los ntawm qhov teeb meem no, uas yog ib qho tseem ceeb heev rau kev xa cov pulses ntawm thaj tsam ntawm lub hlwb. Kev txheeb xyuas ntawm cov teeb meem dawb feem ntau yog ua los ntawm kev txiav txim siab tag nrho ntev ntawm cov neurones tsim. Tag nrho qhov ntev ntawm cov teeb meem dawb nyob rau hauv ib tug txiv neej yog ntau tshaj 175,000 kilometers thaum ib tug poj niam muaj yuav luag 150,000 kilometers ntev dawb teeb meem hlwb thaum muaj hnub nyoog 20 xyoo. Raws li tus neeg laus, qhov ntev no txo qis ntawm tus nqi ntawm 10% txhua xyoo nruab nrab. Muaj peb qhov chaw loj lossis pob khoom ntawm cov teeb meem dawb raws li thaj chaw uas lawv txuas; lawv hu ua Projection (txuas vertically ntawm qhov siab dua thiab qis), Commissural (txuas ntawm ob lub paj hlwb hemispheres), thiab Associate (txuas ntau thaj tsam ntawm tib lub paj hlwb hemisphere).
Grey Matter (Grey Matter)
Grey teeb meem yog qhov tseem ceeb tshaj plaws ntawm lub paj hlwb uas tsim los ntawm thaj chaw ntawm lub hlwb lub luag haujlwm rau kev nkag siab, nco, kev xav, kev hais lus, thiab yuav luag tag nrho cov leeg tswj. Grey teeb meem yog tsim los ntawm neuronal cell lub cev, glial hlwb, thiab capillaries. Txawm li cas los xij, lub xub ntiag ntawm nuropil, uas yog tsim los ntawm unmyelinated axons thiab dendrites, yog qhov tseem ceeb heev uas yuav tsum tau ceeb toom. Nws tseem yuav yog ib qho tseem ceeb hais tias feem ntau ntawm cov neurones yog myelinated nyob rau hauv grey teeb meem tsuas yog nyob rau hauv lub nuropil. Cov teeb meem nyob grey feem ntau yog xim av-grey nyob rau hauv cov xim vim muaj cov ntshav capillaries thiab neuronal cell lub cev. Nws yog qhov nyuaj heev kom nkag siab txog cov txheej txheem ntawm kev hnov qab qhov chaw nyob hauv thaj chaw sib txawv ntawm cov teeb meem grey, tab sis cov kws tshawb fawb tau txheeb xyuas cov cheeb tsam tseem ceeb hauv kev hnov lus, pom, kev tswj cov leeg, kev xav, thiab hais lus. Yog li ntawd, cov teeb meem grey tau qee zaum raug xa mus ua cov khoos phis tawj uas muaj qhov tshwj xeeb sib txawv.
Qhov txawv ntawm Dawb Matter thiab Grey Matter yog dab tsi?
• Cov xim yooj yim ntawm ob daim ntaub yog lub hauv paus rau lub npe, thiab lawv cov xim tuaj yeem txiav txim siab qhov txawv ntawm ob.
• Grey teeb meem ua cov txheej txheem ntawm kev hnov mob muaj nuj nqi thaum cov teeb meem dawb tsim cov kev sib txuas ntawm cov teeb meem grey.
• Cov teeb meem dawb yog qhov tseem ceeb me ntsis (60%) dua li grey teeb meem (40%) hauv qhov ntau.
• Cells ntawm cov teeb meem dawb ntev dua li cov teeb meem grey.
• Tag nrho qhov ntev ntawm cov teeb meem dawb txo qis nrog lub hnub nyoog, tab sis cov teeb meem grey tsis poob qis.
