- Trong btftfne; nhpy caoi chinh tbtfl gian tiem tang cua phau tfng trtftfc vo sou k h i co p i c r o t o y i n kh.nc nhgu khdng n h l e u
2. Ttch btfp 7I iti>iir^, gtan
Htf5ng ngblSng vo v l t r l cuo klcb t h l c h d l l u khien t o klcb t h l c h btfng t i o n g trtf^nt tby cam irhdng nhtfng onh btf^Qg d i n Btfc nbpy cam theo htftfng,, CDO COC onh btftfng oSu s i c din btftfng nbpy cao cuo ntfron.
Kbl thay đl btftfng nghl^ng cuo kfch thfch ^leu kblln , trong do s5 trtftfnt-: bg^ htftfng ntfron b i tfc ebl khi t r a Itfl I p l
kfch tblch bui^ kbdng tboy d d l . Tuy v4*y mSc nhpy coo the bifn r o nbat kbi 30i v i b r i s s chlu tae dyng cuo kfcb thlch btfng, t5c
lo pbu btfp vol t r l n b ttf chuyin dgng cua cac stfl v i b r i s s trong ttf nbl§c k b l con v^t d l chuyen trong kbdng g l o n . Sloona (143 ) cung nb^n t b I y t r l n b ttf ngblSng cuo coc stfl v i b r i s s anb htftfng ttfl bl^u qua 5c c h l . l i l | u quo tfc chl ffipnh n b l t kbl ngblcng cac
stfl v i b r i s s ' t b e o t r l n h ttf ttf nhlen. Dieu nay co tb^ do w phan
bl cuo Cac ntfron tfc c b l trong vo aoo quylt d l n h . Clilnh v l v#y DO t r o o g t a t CO coc l o p t t h l ni^bigc:; CUD t»lnh, chung t d l do cbo
stfl v l b r l s e chlu kicia t h f c b dl§u k h l l u ludn ngbl§ng vl gan stfl v i b r i s s chlu kfch tblcb btfng.
Zao x e t vi- t r l cuo kfcb thfch di§u k h i l n trong trtftfng tby coo Chung tfll nbpn tbay kbi kfch t h l c h d l l u kbilo tf trung taJB trtfJâ: tby com, t b l dap Snc cua ntfron d l l vtfl kfch tbfcb d l l u k h l l n ©anb htfn so vtfl dop ung t r o Itfl l e i klcb thfcb htfng. Troog trtftfng btfp nay dtftfl onh htfóng cua klcb thfch đl tfnb nbpy cos t b e o b t f ^ : euo ntfron t b l hlgn r o n e t n h l t . i^tf3^on
nguygn pbot KJJICTU l u c nay cbl t r a Itfl l©i klcb^tbfch tf ât bol htftfng n b l t d j n b , ttfc l a ntfron trtf thonh nupy com thcôbtfo-ng tt^t each r o r a n g . ^ «^ny g i a l dopn tfc c u l k l o r l t dal ( den
60 (Bsec), tf sitft GI ntfron con quori uot dtftfc t l o l <3o«o ^^ <^^^
124
Hgtftfc I p l , kbl kfcb t b f c b dieu khiln tf xo trung t t e trtftfng tby COID btfn so vtfi kich tbfch htfn^:, t h l dap tfng t r o Itfl I p l k f c b t b l c b d l l u k b l l n a© ylu btfn so vol dop tfng t r o Itfl I p l kfcb tbfch btft^. Trong trtf&ng btfp nay dtftfi onb htftfng cup kfcb t b f c b đl ntfi^on c h i b}. iic cbl nhg tf cipt btftfng npo dS,
n^n otfc nbpy caio theo btftft^ kboag coo, ntfxon trtf nin nbpy ca*
theo htftfng nâc each ttftfng d l l . i^oe nay g l a l dopn tfc cbl nglo
htfn (10-60 Dsec) va khdng quan s a t dtftfc g l o l dopn tfc c h l boon toon.
^^sânQ }r^^,^^ t r a 1^1 l a i kich thlch dieu k h l l n
quo y l u so vtfl dap inE t r o Itfl I p l kfcb thfch hi5ng, t h l tfnh
nhpy CO® t h e o btftfng tf myt so ntfron khdng x u l t hign.
Kbtf vyy, tt^y tbu^c voo vj. t r f cuo kfcb thfcb d l l u k h i l n va kfcb thfch bfeg t r o n g trtftfng thy c a o , mo 5o chl htfScg tfin
CO t b i mpnh hay y l u . Dllu do anb btftfng din stf too thonh vo <i§
nbpy c a s t h e o btftfng cua ntfron.
lSh$Q (JJ.nh t r e n cua cbuii^^ fccJi cunc d'^^c sac oLgD bang cac k i t quo thtfc nghifrrcuo fbapoaki ( 6 5 ) , Khi nishlen ctJu tac
dgng tjua I 9 I gitfo qvo crlnh btfDg phln va 5a chl trSn aOroa vune cao g l a c - s o o a cac g i a da nhgn thiy rang: <7ap iJng cuo ncfroo d^l V(5l kicb tb£cb h5tt,^ g i a o m^ob nhet kbi kloh th{ch diSu k h i l n rtfi vao brucg Hhm trtiSog tby cam, t i c In khi dap tfng cua od'OG uoi T>5i k l c b tbicbdieu khi^o agah n b a t . i)ilu (Jo co bgbia i o 5c c b l d j t laJc c j ^ dpi khi co <3op me bifng phln oj^c
d e i .
SlBona cung co ohjn x e t ttfóng ttf k b i nsl^l^n c&u trtf^og 5c cb5 cue nc^bn vo cao csu g i o o - s i a e 5 cbugc (1^:3). Trt?5ng *
uc c h l cuo riC?ro0 I 5 Q ói5t kbi kfcb t h l c b rsPi^T^ôss?! v i b r i e a
cb£nh ( p r i n c i p a l v l b r l s e ) *roog trtfóag rhw csts cus ntfron, t;i5c iS v i b r i s s s^y iwog phln eenh o b i t cbo tn^t cSu ti-uc ^ ^ ^ i " hay cau triic tcJduQ.
SJ> oh^'Dg kfit qua vo nb|n djnh vrSn co thk thSy ^ rSog
t r f c ^ kfcb tbfcb d l l u k b l l n va kfch chfch bSne tronc trtftfng
tby CO©. Kfch tbfcb dieu khiSn cent gSn trung tSo, CSQE ray tfc cbl oonb vo do do ©tfc nhgy coo tbeo btftfog cua ntfron caug ldo«
Dieu noy cung co t h l b l l u dtfgc khi chiSni: ta cdng nh5n
rang cac ntfron croug vo L«O dtfgfc quj cy ajjc lỉ^ne I 5 Q coc luc^ng xune Us^ng btftfng tiki, ^^a ^hy caa t b l v i b r i s s l a chfnb (ttfc l a tf troui;- -Cilm trutfng thy caia) cua ntfron tbu^Jc cau t r u e
•đun noy, t h l dSng tbtfl cung l o thy cam chl pby cua n h i l u
sđun k b a c . kbl v i b r i s s chfnh b|, kfcb tofch^ no BC lorn btfog
phln kbiing nbtftog ntfron thutJc raodun ttftfng tfng <v5l ctftfng d$
S0nb va t h H g l r n t l e o tsn^* n g l n ) , m con gay hucR phln nhilu
ntfron tbu^c cac ođun kh$c» trong dS co hg thing ryng lỉn
nhutog ntfron trung gian tfc c b l . Dtftfl anii h^/tfog dc chl cua nbtfnf^ ntfron nay, dap &n^ cus ntfron dtfg'c n^bifin ctfu bl £3a»
D«nb tf nbtfn^: btftfog n b l t d l n h . JJO do otfc nhay caa theo btftfng cua ntfron cao htfn so vtfl trtftfng; bjfp kfcb thfch d l l u k b l l n n i s
78 trunn t3a trtftfng tby cam.
Mgt d#c dl§D dan^i cbu y t r o c g hopt; d^nfc clch hcPp v l ni|t khdni:: g i a n cua ntf1^on vung vo nao cao glac-eooa io sj? tbay đl nbonb chong ht^tfog nbgy caa cua ntfron kbl chay dtil vJ t r f
ttftfng d l l cue kfcb thfcb dihi kblln atung quabb kfch tbfcb
btfng.
Trong trtf&ng h ^ b a l kfcb tbfcb t a c djM^t^ t^Sn bal êTl v i b r i s s cuoi^^'; nam t i ^ n ©i^ hang ngoDcr, t b l kbl thay đl v l t r f cnnj kfch thfch dlSu k h l l c ttf trtftfc ra s s u , bôc ttf sou r a
trtftfc 80 v o l kfcb thfch htfng, tf dpi do s i trtftfng h ^ btftfng tfc chl cue otfron b i fc^ay d o i , troog do co nblSu trtfóng btfp bol htftfng noy n^tfS^ nan Diaụ
SV hl^n d a i b0^f: dap tfnr clnf r o btfn Lbl kfch thfch
d l l u k b i l o thtf bol t i c d^ng tf v l urf Igch vol kfch thfcL dl^u k h l l n tbtf o b i t atit goc 9 0 ^ , ttfc l a bal kfcb tbfch nets khac
« l t 6 «
hang nbaụ Con kbl kfcb thfch d i l u k b l l n thtf n b l t tf g5a kfch tbfch htfnr: btfn kfcb t h f c b d i l u iUilIn tbtf hol» ôc du bol
kfcb trtifch cunc 0 o«c b^nn^ vl cung ts^j; bdn, stf b i l o đl b u ^ pbao tfae vSn 3?ay vọ ( 5 khoang 5^ /. so ntfron dcg^ nohlSn ciJu).
fcbtf v§y, cfnii uh^y ca© ijheo btf5ni: v&a dỉ^c hlnb tbanb dtftfl onb bu^^ cua tfc ciie do kfch cafch d l l u Mjlln htftfng tSo
6*y r a l o l nbonb cnon,: uhay d l i kbl ihay đl vj. t r f cun kfch
thfch Day trong tnt^nr, tby cm cua ntfioc.
Stf blon đl ^iits deo" tfnh nhpy coQ theo btftfng; c m g
quan sot tb5y t r o n r cac i;hf n^:bl§G3 CUD cac tac f l a kblc kbl kfcb thfch vo noo caa tuoc-soma ban£; boa c u l t . Vf ay
ile:!raodrov vl C^IMC s\i (10) da nh^n t h I y kbl tboy d J l vj. t r f
cac dlocD d^/c k i c h chfcb nhfin cgo, hi^Yip cbay c^á cus otfron
cunt uhay d d l . B$v d l l a kfch thfch nam cl*^n dim gbl di^n t h l vl thuy c o r o n a l l s , t o l tfc cbl cbu ylu x u l t hltfc tf btftfng 160° (pbfa dtftfl) va 2/0^ (pbfa s o u ) , h^itgc I 9 I nlu diem gbl dl^n t h l n?4t5 íh^Of t b l 5c c h l cbu ylu tf htftfng Ô (pbfa tr3n )
vl htfôf ^^^ (p^^jfa t n / t f c ) . ^
libtfDij k i t QUa tri^c dSy, kbcng nhtfog; chtfu;:: t o r^og cac ntfron crun,^< glsn & c h l phSn b l trong kb^n{: cion theo oyt
t r l u b tijf n b l t dj-nn^ nis con c b i :eo B^ too t o i nbtfng csli l l § n
b | gltfa v l t r i cua notion dtf^c boat bos vtfl d | c dlSca anh btfc^^, CUD no d l l Vtfl cutfcnung cua ntfron ngblen ctfụ
I r o n g d l l u kl^n kfcb chfcb ttf n h l a n , co the ouUi; ât luc
CO n b l l u n:;*ron eun{; htfnG pbIn, cun^: tbom s i s vno cỉc qua t r l n h 3?tf l y tbcuf^ t i n * i^btf nbyn djnb coa nhlou t i e gia c i c ntfron dtftf^c htfntj, >bln cunf; v^i cac otfron tfc c h l do tpo x;honb cac v l ođun, c.^c siđun, c I c t§p qu*3n nôon pbfin b l theo cac c b l l u Midnf^ r l s n khac nhau tron{r vo ban c5u d a l naO ( 1 , ^ , S'/,
2^^ 5 ^ , >*, '^3), sonc nbtf co tryc ttf phSn bo i^:ltf8 cac ntfron
IL^/
top gltfQ c^c ncfron t r o n ^ cm^ isyt ©đun, c^yt t f p qu5n va gltfn
c«jc ncrron cron^ coc mđun, cac t | p quun khac nbau, oa c^c tfnb
cbIc d e t e c t o r cua ntfron dtfg^ chl blyn r o rlr^ trong qua t r l n b
t l l p nbyn chdnp: t i n .
D^c t f n b kbon^^ ^ i a n nay con dtfgc l a e sanc- t o k b l pbfin t f c b a l l l l ^ n bS gltfin vj. t r f cua kfch tbfot^ d l l u kblen cr:mg
trtftfnc thy ca® va btf5n(^ nbgy cecj chfnh cua ntfron. *^hl stfl chj.u kfch chfcb d l l u kblen pb£n bo in?en cun.^ baaj vl 0 pblo sau s^'l cblu kfcb thfcb btfoc,, tfc c b l y u l t bl^n chu ylu tf htftfUtr 270^ vl
o \ i^gtftfc I 5 I k b l s^l chj.u kfch uhfch dieu kiilt^n tf pbfa trtftfc, t b l 5c c b l x u l t hlgn chu y l u tf htftfng >-0^ vo htftfng- l^-o"*, &bl ôfl cbju kfcb t;hfch d l l u kblen pban b l khac banc, nlu tf pbfa
t r 3 n s^fl chj.u kfcb ohlch btfn^^, tfc che chu yfxu tf b'tSnc '^^ va 9CJ?
nlu tf pbfa dtftfl - ' c c b l cbu ylu tf btftfng 1^^ vl 270^^
Jibtf vyy htftfng tfc chl chu ylu tf d?iy ngtftfc vtfl t r l n b ttf
chuyin di^n^^, cua coc stfl, bay nol each khac la btftfng nhpy ca» ebfnb phu as^p v^l t r l n b ttf chuyen dlcb ttf nhlen cog cac B^i
v i b r i s s i;ron^: kbdn^^ g i a n .
BIU tfnb din v^ t r f hlnh chieu cua tby ogsi the v i b r i s s
t r # n vo 000 care ^^lac-sOB© stf c^p do quay u^t -oc V^ so vtfl vJ t r f t r e n D^C cua d^g v^t ( v ^ , yO, 9 ^ ) , t h l nbtfng k l c qua
tbu dtftfc cua chung t;dl cunr e*n vtfl k i t qua tbu dtftfc trong cdnG c r l n n ' c u n Alearnndrov va C^JPHC stf (11) khi kfch thfch vo nao bang g l u t a o a t .
Cac k i t quo tvQn cho pbep kbing dlnh r a n t cac ntfron trunfi glnn tfc c u l trong m^t oodun co anb bit0nB theo r.^t t r § t ttf nbic dlnb d i n chu»c nung cua ntfron d\JiQ^ mbiM ctfụBlIu nay
cunr pbu btfp vtfl cac i3n l l g u ngblen ctfu v l blnb t h a i oua l o ^ l ntfron trunf; gian tfc c h l chu ylu (ntfron hlnh g l o ) tronf; vo uao
(14 1 5 , l^f ^9» 5^» ^^)« ^^^^^ ^^^ ^^^ ^^^ '''^'^» ^}^^ nhimg
litfron hlnb g l o pbSn nhanb ri^n£ trong mđun va cbu ylu vudng goc vtfl cac tbuy cuo noọ
^ 12i^ m
Ttf nlitfn(: ph3n cfcb trSn cbung t d l t b I y rBnj^ tfnb nhpy cao theo hiftfô cua ntfron b l l n d^l nbanh chon;:? ca v l ogt kjidng gian ISn thtfi ^rlan kbl hôt boa cac ntfron i5c cbl trung g l a o bang each ttf nblen hay nban t p o . % bien đl •^alm deo** nay co l i e n quan d i n quo t r l n h tfc chl tron£ vo nao VR no l a dye dice: chung d l l vtfl vo nao COD glac-sooa va vo nao t h i gloc
( 6 6 , 6 7 ) .
libtf vSy tfnb •'taiSo deo" cua cl bao thuu klnl; khdng pbal
c b l t h l blgn t r o o g nhtft:^; qua crlnb dlen ra tiftfti^^; d l l cbgis nbtf pbao yp CO d l l u k l f o , t r f nhtf ( 3 9 , ^ u , ^ l ) aa ca trong nbtfnr
qua t r l n b dlen ra nhanb cbong tron^ cac c l u t r u e tton klnh
( 6 b ) ,
l a y vyy canag t o l khcng tuy§t del hoa val t r o cua cac qua t r i n b b l l n doi ''mlm deo" trong vo nao k b l pbfin t i e b cac
ludcg btftfng t a s . Ghac clfjn ll trmig vo bao con t^n t g l nhtfng ntfron, faôc uhi/n^^ b§ vhlnp ntfron co pban 5nc ^in d j n h . D I I vtfl
h§ t h i n g nhgy cam 2ci5e c l ^ c , do co t h e l a nbtfng mv*ron dtf^c htfng phln k b i kfcb thfcb rtfl vao trung tgns crii^n^^ tby c^*m . Cbtfng ntfron noy co pbon tfuị; vtfl ctftfng dg m^nh nhat vo thai
gian t l l o t a n c ng*n n b l t . Cbung kbt^ntr b i tfc c h l dtftfi anb htftfng cua kfch t r f c b d e l . Con nbtfng ntfron kbac vtfl phan tfnr
cb0» htfn tf nfctfri^:- siic di^ khac cbau c5 the do b l rac d^ng hoi
Dbm£ qua t r l n b ac c h l nao d o . ^butog qua trlnl:. nay co t a c
d\?n£ Isro y u l t bigd va b l l n đi tfnh nbpy cata theo btf5ng tf ntfron icbl co kfcb x'hfch d d l .
libtf vyy h§ chlnj" nóron phan tfnc nhanb co t h l dao bao cho qui t r l n b i ^ ^ c bieti kfch t,ifch> con nbtfng ntfron ph^r: tfog.
cb^m htfn crong nhtfng: kboang tutfl t i a n nhet dj.ab se guyet dj.nh
Stf blnh thnnb b% tli^n^i pfiSn tfcu cac d^c dim cua kfch t b f c b , ttfc l 5 lam n h i ^ vy qhun b l l t kfcb talcb. Ctf c b l bopt dj^ng
nay cug cac ntfron tron^j vo naO cuiJt]> dutfc t b l hl^n qua stf tung
sc Itftfr,,! coc ntfron nh^y cm tbeo ai^ui, trotn^ i;l nbtfng ntfron
» 129 «
T& Gat ca nhunjr, Uicu ubi^n ỵec uren dSy cho phep chung
Mdi nh§a dj.nb r^ni, tfnti c h i t cbtfc nauf cun cnc ntfron vung cao
glac^sooa dtftfc blnh tbanb nbtf qua t r l n h 5c c h l co chpn I p c
ngay ben t r o n r vo ban c l u dpi n a o . Hope hOa cac qua crlnl: tfc c h l nay blnii cac kfcb thfch del ty rihleu ae lots x u l t blgn ,
hope locn b l l n đl tfnh nhpy cm theo btf^ng cus ntfron. ifnh
c h i t d e t e c t o r nay I p l co t n l b i l n đl s^vt cacb nhanh chong , ffilm deo crong qua uilnb xtf l y tbdng t i n . Hgtftfc I p l lara j i u quo t r l o b t5c c h l bant: cac c h i t t i l l khnn^ cua t^iU^ri se l a o o l t hoyc laQ b l l n d d l tfnb chat d e t e c t o r vtfa dtf^. hlnh chanb iibl co kfcb t.ifch d l l u k b l l n btftfnr^ t s o ttf nhl^n. i>llu do nol l e n v a l t r o q u y l t djnh cua i^ c h l ben trong vo nao khdog nbtfng d l l vtfl stf blnb tnanb cac chi^ nang cua neuron vung vo neo caO glac-sOBSfSa con datn bao cbu stf b i l n doi êt clcb t l n b v l , a l o
deo nbtfng dgc tfnb noy pbu btfp vtfi atf t e c dgnc. cvo cac kfch
m lyo ^
T^ v l j c danb gio c I c kIc qua D,c;;bign c5u cbung t d l r u t sa
dtftfc m^t s i k i t lu§n r^^^- t
1 . Cc cbl btftfut; i^am do klcb thfcb d l l u k b l l n gay ra da
loa glon dnp tfng cua nc^on troog nhtfni^; htftfng n h l t dj.nh vo do do da đn d i n nbtfcg b l l n d e l sau s i c trong d ^ tfnb d e t e c t o r cua ntfron. 62 jv t i n g su ntfron nguySn phat khdng nbpy câj theo htf5n^: fitftfc n(:^blen Ctfu da trtf thonh nbtfng ntfron nbpy cos theo btftfng. Vtfl nbtfng ntfron nguyen pbsx; nhpy com tboo btftfng, tfc c b l htftfng tdo CO t a c d^^r lacj tanp: tfnh nhpy cam (tf 56 >^ t5ng s5 ntfroo dtftfc ngiilen ctfu)^ hô^c lao thay d5i atftfog nbpy car. chfnb
(tf k l /v tjctftfct: btfp).
2 . Mtfc nbpy caa t b e o htf'w c ^ otfron b i l n d5l tboo aigt quy l u g t nblu d j n h , pby vhu«c voo khoang tibtfi gian gltfa kfcb
cbfch d i l u k b i l n va kfch t b f c b htfng s Tcfnb nhpy cam tbeo hxtdts^
x u l t hlfn va o l t d i tron;: khoang ^btfi gian gltfa bal kfch ichfch
ll > . ^ a s e c , tronn; do vfnh nbpy cao cao nh?1t xoy ra tf kboang
20-pO iBsec. u ao ,i trtfS^g btfp d^c tfnb bien a d i dtftfc duy t r l
tbeo t l l n cxflnh chtfl g l o n , Uv^on bi ifc ch* v a ' c b t ^ t kbol tfc c h l troo2 cuaf: m^t btf^of.
> . Htftfuf: va ©tfc nbpy Cam theo btf5ng cua ntfron cung b l l n đl l l n b hopt i by t-iU^c vao yeu t l kbdng g i a n . litf^ng nbpy cam
chfnh zvvni^. v$i btftfng chuyen dene tbeo t r l n b ttf cgc stfl
v i b r i s s , con ^iab nbpy csa dpt otfc cao nbat k b l kfcb tbfcb
d l l u k b l l n tf trun?: tStn tjrtftfng tby c a o .
ir^ Plcrouoxln - c h i t d l l khaSt-; cua gaona«8S»lno-but"yflc
axle dtftfc dúo vlo vo ban c l u dpi nao bang pbtftfng pbep v l dl^o dl da lata glon; bo-Jc l a o ^ I t t i c dun^ cua tfc che btftfng tm dii
v^h Btf blnh tbcnb vl b l l n d d l cfnh ch^t d e t e c t o r cua ntfron vnxm: cats gloc—30Oa#
» 1^1 a
5» ic chl btf5ng tam do kfch thfch d i l u k h i l n gay r a l a
5c cbe phao" sinb ngoy tx^n^ vo nao, co ban c h i t UABA vl dong
vai t r o quan trpn,*: trong stf b l n h ' t b a n h cac dgc dilcu chi5c nang CU3 Cac nc?ron vo nao vung caia gioc-soraạ
gAl LUJj THAU KliAU
1 . B3 Cdng Iluynb
Vai n e t ve stf bopt dyn^;; cua cac t e bao thSn kinb trung
00nB (tbdng bao X).
Tpp cbf slnb l y hpc Vigt horn 1975, 5!.12, 1*^2.
2. I& Cdng liuynh
Vai net vl atf bopi; dyn^< cua cac t l bao fban kinb t r u n g
tftfng (tbdut^ bao 2).
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