Khutu Lanu Wolankhulira Wamkulu

MUNGATHE kutsinzina pamene simukufuna kuwona. Mungathe kugwira mpweya pamene simukufuna kununkhiza. Koma simungathe kutseka kotheratu makutu anu pamene simukufuna kumva. Mwambi wakuti “kutembenuzira khutu logontha” uli wanjerengo. Kumva kwanu, mofanana ndi kugunda kwa mtima wanu, kumapitirizabe kugwira ntchito ngakhale pamene mwagona.

Ndithudi, makutu athu akugwira ntchito nthaŵi yonse kutitheketsa kumva zomwe zikuchitika motizungulira. Iwo amasankha, kusanthula, ndi kutanthauzira zimene timamva ndi kuuza ubongo. M’malo obindikiritsidwa a ukulu wa masentimita 16 mbali zonse zinayi, makutu athu amagwiritsira ntchito malamulo a acoustics, mechanics, hydraulics, electronics, ndi masamu apamwamba kukwaniritsa zimene amachita. Ngati kumva kwathu nkosavulazidwa, lingalirani zinthu zina zimene makutu angachite.

◻ Kuyambira pa kunong’ona kwakung’ono kufikira pa kulilima kwa kunyamuka kwa ndege ya jet, makutu athu angathe kuchita ndi kusiyana kwa kufuula 10,000,000,000,000. M’kalongosoledwe ka sayansi, umenewu ndi ukulu wa madecibel 130.

◻ Makutu athu angadziŵe ndi kusumika pa kukambitsirana kumodzi m’chipinda chodzaza ndi anthu kapena kudziŵa kaimbidwe koipa koimbidwa ndi chiwiya chimodzi m’gulu la oimba la ziwiya zana limodzi.

◻ Makutu a anthu angadziŵe kusintha kwa madigri aŵiri kumene kukuchokera mawu. Iwo amachita zimenezi mwa kuzindikira kusiyana kwakung’ono kwa nthaŵi yofikira ndi mphamvu yake pa makutu aŵiriwo. Kusiyana kwa nthaŵiko kungakhale kwakung’ono kwenikweni kufika ku mbali imodzi mwa khumi ya miliyoni ya kamphindi, koma makutu angadziŵe zimenezi ndi kuzipereka ku ubongo.

◻ Makutu athu angazindikire ndi kusiyanitsa pakati pa mawu 400,000. Zochitika m’makutu athu mwaluso zimasanthula mawu ndi kuwagwirizanitsa ndi awo osungidwa mosungira chikumbukiro mwathu. Mmenemo ndi mmene mungadziŵire ngati kaimbidwe ka nyimbo kaimbidwa ndi violin kapena chitoliro, kapena kuti ndi ndani amene wakutumizirani lamya.

“Khutu” limene timawona kunja kwa mutu wathu liri kokha mbali imodzi, mbali yowonekera kwambiri ya khutu lathu. Mwinamwake ambirife timakumbukirabe masiku athu a kusukulu kuti khutu linapangidwa ndi zigawo zitatu: khutu lakunja, lapakati, ndi lamkati, monga mmene amadziŵikira. Khutu lakunja nlopangidwa ndi “khutu” lozoloŵereka la khungu ndi chichereŵechereŵe ndi ngalande ya khutu yotsogoza ku mwinikutu wokhala mkati. M’khutu lapakati, mafupa atatu aang’ono kwambiri m’thupi la munthu—malleus, incus, ndi stapes, odziŵika mofala kukhala hammer, anvil, ndi stirrup—amapanga ulalo wogwirizanitsa mwinikutu ndi oval window, khomo lopitira ku khutu lamkati. Ndipo khutu lamkati nlopangidwa ndi ziŵalo ziŵiri zowoneka zachilendo: mpukutu wa ngalande zozungulira (semicircular canals)zitatu ndi cochlea yokhala ngati nkhono.

Khutu Lakunja—Cholandirira Chophunzitsidwa

Mwachidziŵikire, khutu lakunja limagwira ntchito yosonkhanitsa mawu kuchokera mu mpweya ndi kuwapereka ku ziŵalo zamkati za khutu. Koma limachita zambiri kuposa pamenepo.

Kodi munayamba mwalingalira ngati mpangidwe wokhota wa khutu lakunja umatumikira chifuno chapadera? Akatswiri asayansi apeza kuti mphako yapakati pa khutu lakunja ndi ngalande yakhutu zinapangidwa motero kotero kuti zikulitse mawu, kapena kuwamveketsa ndi mlingo wa kuwirikiza kwinakwake. Kodi zimenezi zimatipindulitsa motani? Zimangochitika kuti mikhalidwe yambiri yofunika ya kalankhulidwe ka anthu imakhala yofanana.a Pamene mawu ameneŵa akuyenda kupyola khutu lakunja ndi ngalande ya khutu, amakulitsidwa nthaŵi ziŵiri kuposa mphamvu yawo yoyamba. Umenewu ndi uinjiniya wa mawu a acoustic wapamwamba kwambiri!

Khutu lakunja limachitanso mbali yofunika kwambiri m’luso lathu la kudziŵa magwero a mawu. Monga zatchulidwa, mawu ochokera kumanzere kapena kumanja kwa mutu amazindikiridwa ndi kusiyana kwa mphamvu ndi nthaŵi yofika ku makutu aŵiriwo. Koma kodi bwanji ponena za mawu amene amachokera kumbuyo? Kachiŵirinso, mpangidwe wa khutu umagwira ntchito. Kumapeto kwa khutu lathu kunapangidwa kotero kuti kumalimbana ndi mawu ochokera kumbuyo, kupangitsa kutaika kwa ukulu wa 3,000- mpaka 6,000-Hz. Zimenezi zimasintha mkhalidwe wa mawu, ndipo ubongo umawatanthauza kukhala ochokera kumbuyo. Mawu ochokera pamwamba pa mutu amasinthidwanso koma m’bandi ya kuwirikiza yosiyana.

Khutu Lapakati— Loto la Makaniko

Ntchito ya khutu lapakati iri kusintha kulira kwa mawu kwa acoustic kukhala kwa mechanic ndi kuwapereka ku khutu lamkati. Zimene zimachitika mkati mwa chipinda cha ukulu wonga wa nsawawa chimenechi ziridi loto la makaniko.

Mosemphana ndi lingaliro lakuti mawu ofuula amapangitsa kugwedera kwakukulu kwa mwinikutu, mafunde a mawu amachita zimenezo mwapang’ono kwenikweni. Kugwedera kwakung’ono kumeneko sikokwanira kupangitsa khutu lamkati lodzazidwa ndi madzi kuyankha. Njira mu imene chopinga chimenechi chimagonjetsedwera imasonyezanso kupangidwa kodabwitsa kwa khutu.

Kugwirizana kwa mafupa atatu aang’onowo a khutu lapakati sikuli kokha kokhoza kuzindikira komanso kosalakwa. Kukumagwira ntchito monga dongosolo la kutsitsa ndi kukweza, iko kumakulitsa mphamvu iriyonse yobwera ndi chifupifupi 30 peresenti. Kuwonjezerapo, mwinikutu ngwamkulu kuposa patsinde pa stirrup ndi chifupifupi nthaŵi 20. Mwakutero, mphamvu yoikidwa pa mwinikutu imaunjikidwa pa malo aang’ono pa oval window. Zochitika ziŵiri zimenezi zimakulitsa mphamvu pa mwinikutu wogwederayo kuwirikiza nthaŵi 25 mpaka 30 kuposa oval window, kokwanira kupangitsa madzi a mu cochlea kuyamba kuyenda.

Kodi nthaŵi zina mumapeza kuti kuzizira kwa m’mutu kumayambukira kumva kwanu? Izi ziri chifukwa chakuti kugwira ntchito kwabwino kwa mwinikutu kumafuna kuti mphamvu ya mbali iriyonse ikhale yofanana. Mwachibadwa izi zimachilikizidwa ndi kachiboo kakang’ono, kotchedwa chubu cha Eustachio, kamene kamagwirizanitsa khutu lapakati ndi kumbuyo kwa dongosolo la mphuno. Chubu chimenechi chimatseguka nthaŵi iriyonse pamene timeza ndipo chimatulutsa mphamvu imene imakula m’khutu lapakati.

Khutu Lamkati—Mapeto a Ntchito ya Khutu

Kuchokera ku oval window, timafika ku khutu lamkati. Zingwe zitatu zoongoka, zotchedwa semicircular canals, zimatitheketsa kukhala olinganizika ndi kulingalira bwino. Komabe, ndi m’cochlea mmene ntchito yakumva imayambira.

Cochlea (kuchokera ku Chigriki ko·khliʹas, nkhono) kwakukulukulu iri mtolo wa mitsempha itatu ya mphako, kapena ngalande yodzaza ndi madzi, zokulungana mozungulira mofanana ndi chikamba cha nkhono. Mitsempha ya mphako iŵiri njogwirizanitsidwa pansonga pa chozunguliracho. Pamene oval window iyambitsidwa kugwira ntchito ndi stirrup patsinde pa chozunguliracho, imapita mkati ndi kunja mofanana ndi pisitoni, kukhazikitsa mafunde a hydraulics m’madziwo. Pamene mafunde ameneŵa akupita ndi kuchoka ku nsongako, amapangitsa zipupa zolekanitsa mitsempha yamphakoyo kufutukuka.

Mphepete mwa chimodzi cha zipupa zimenezi, zodziŵika monga basilar membrane, muli chiŵalo chomva kwambiri chotchedwa Corti, chotchedwa ndi dzina la Alfonso Corti, amene anapeza maziko owona a kumva ameneŵa mu 1851. Mbali yake yaikulu iri ndi mizere ya maselo aubweya omverera, okwanira 15,000 kapena kuposapo. Kuchokera ku maselo aubweya ameneŵa, zikwizikwi za minyewa ya mitsempha imapereka chidziŵitso chonena za liŵiro, mphamvu, ndi ukulu wa mawu ku ubongo, kumene lingaliro la kumva limachitika.

Chinsinsi Chivumbulidwa

Mmene chiŵalo chotchedwa Corti chimaperekera chidziŵitso chocholoŵanacholoŵana chimenechi ku ubongo chinali chinsinsi kwa nthaŵi yaitali. Chinthu chimodzi chimene akatswiri asayansi anadziŵa chinali chakuti ubongo sumavomereza ku kugwedeza kwa mechanic koma kokha kusintha kwa electro-chemistry. Chiŵalo cha Corti mwanjira inayake chingakhale chimasintha kuyenda kosinthasintha kwa basilar membrane kukhala mauthenga a electrical olingana nawo ndi kuwatumiza ku ubongo.

Zinatengera katswiri wasayansi wa ku Hungary Georg von Békésy zaka 25 kuvumbula chinsinsi cha chiŵalo chaching’ono chimenechi. Chinthu chimodzi chimene anapeza chinali chakuti pamene mafunde a mphamvu ya hydraulics anayenda kudutsa mitsempha yamphako mu cochlea, amafika pachimake adakali m’njira ndi kukankha basilar membraneyo. Mafunde oyambitsidwa ndi mawu okhala ndi mphamvu yaikulu amakankha membrane yapafupi ndi patsinde pa cochlea, ndipo mafunde a mawu okhala ndi mphamvu yochepa amakankha pa membraneyo pafupi ndi pansonga. Mwakutero, Békésy anamaliza kuti mawu okhala ndi mphamvu yakutiyakuti amatulutsa mafunde amene amapinda basilar membrane pa malo apadera, kupangitsa maselo aubweya kuvomereza ndi kutumiza zizindikiro ku ubongo. Malo a maselo aubweyawo akavomereza ku kuwirikiza, ndi unyinji wa maselo aubweya amene ayambitsidwa akavomereza ku ukulu.

Kalongosoledwe kameneka kakumveka bwino kwa zinthu zopepuka. Komabe, mawu ochitika m’chilengedwe mochulukira samakhala opepuka. Kulira kwa chule wamwamuna kumasiyana ndi kulira kwa ng’oma ngakhale kuti angakhale a kuwirikiza kofanana. Izi ziri tero chifukwa chakuti mawu aliwonse ngopangidwa ndi kamvekedwe kake ndi mamvekedwe ena ambiri apamwamba. Chiŵerengero cha kamvekedwe kapamwamba ndi mphamvu yawo yolingana nawo kamapatsa liwu lirilonse mpangidwe wake wapadera, kapena mamvekedwe. Mmenemu ndi mmene timazindikirira mawu amene timamva.

Basilar membrane ingavomereze ku mamvekedwe onse apamwamba a mawu mosiyanasiyana ndi kuzindikira kuti alipo angati ndipo kuti ndi mamvekedwe apamwamba otani amene alipo, mwakutero kuzindikiritsa mawuwo. Akatswiri a masamu amatcha dongosolo limeneli kukhala kusanthula kwa Fourier, akumalitcha ilo ndi dzina la katswiri weniweni wa masamu wa ku France wa m’zaka za zana la 19 Jean-Baptiste-Joseph Fourier. Komabe, khutu lakhala likugwiritsira ntchito njira yamasamu yapamwamba imeneyi kwa nthaŵi yonseyi kusanthula mawu omvedwa ndi kupereka chidziŵitsocho ku ubongo.

Ngakhale tsopano lino, akatswiri asayansi sali otsimikiza ponena za zizindikiro zimene khutu lamkati limatumiza ku ubongo. Kufufuza kukuvumbula kuti zizindikiro zimene zimatumizidwa ndi maselo onse aubweya ziri chifupifupi zofanana mu nthaŵi ndi mphamvu. Mwakutero, akatswiri asayansi amakhulupirira kuti siziri zinthu za zizindikiro koma zizindikiro zopepuka zenizenizo zimene zimapereka uthenga ku ubongo.

Kuti timvetsetse kufunika kwa zimenezi, kumbukirani maseŵera a ana pamene nkhani imaperekedwa kwa mwana mmodzi kupita kwa wina mu mzera. Zimene mwana womalizira amamva kaŵirikaŵiri sizimafanana ndi zoyambirira. Ngati chizindikiro, monga ngati nambala yatumizidwa m’malo mwa nkhani yovuta, mwachidziŵikire sidzasokonezedwa. Ndipo mwachidziŵikire, zimenezo ndi zimene khutu lamkati limachita.

Mosangalatsa, njira imene ikugwiritsiridwa ntchito lerolino m’madongosolo olankhulira opambana, yotchedwa pulse code modulation, imagwira ntchito mogwiritsira lamulo limodzimodzilo. M’malo motumiza tsatanetsatane wa chochitika, chizindikiro choimira chochitikacho chimatumizidwa. Mmenemu ndi mmene zithunzi za Mars zinatumizidwira pa dziko lapansi, m’zidutswa za manambala, kapena mmene mawu amasinthidwira kukhala zidutswa kuti ajambulidwe ndi kuseŵeredwanso. Koma, kachiŵirinso, khutu ndilo linayamba!

Chozizwitsa cha Chilengedwe

Makutu athu sangakhale akuthwa kwambiri kapena akumva msanga pakati pa makutu osiyanasiyana, koma mwachiwonekere analinganizidwa kuti akwaniritse chimodzi cha zofunika zathu—kufunika kwa kulankhulana. Iwo anapangidwa kuti avomereze bwino makamaka ku mkhalidwe wa mawu a anthu. Makanda amafunikira kumva mawu a amayi awo kuti akule bwino. Ndipo pamene akukula, amafunikira kumva mawu a anthu ena ngati ati akulitse luso lawo la kulankhula. Makutu awo amawalola kuzindikira kusintha kwa kamvekedwe ka chinenero chirichonse mosamalitsa kotero kuti pamene akula amatha kuchilankhula monga mmene mwini wa chinenerocho angachitire.

Zonsezi sizotulukapo za chisinthiko chakhungu. M’malomwake, chida chathu chozizwitsachi chinachokera kwa Mlengi wachikondi, Yehova. (Miyambo 20:12) Makutu athu alidi zozizwitsa za chilengedwe ndi zisonyezero za nzeru ndi chikondi cha Mpangi wathu. Mwakuwagwiritsira ntchito iwo tiri okhoza kulankhulana ndi anthu anzathu. Koma koposa zonse, tiyeni tiwagwiritsire ntchito kumvetsera ku nzeru zopezeka m’Mawu a Mulungu, kotero kuti tiphunzire kuchokera kwa Atate wathu wakumwamba, Yehova Mulungu.

[Mawu a M’munsi]

[Chithunzi patsamba 15]

(Onani m’magazini yeniyeni kuti mumvetse izi)

KHUTU LAKUNJA

Khutu

Ngalande ya khutu

Mwinikutu

KHUTU LAPAKATI

Hammer

Anvil

Stirrup

Chubu cha Eustachio

KHUTU LAMKATI

Semicircular canals

Oval window

Cochlea

[Chithunzi patsamba 16]

(Onani m’magazini yeniyeni kuti mumvetse izi)

COCHLEA

Chithunzichi chikusonyera ngalande zamphako zitatuzo zitafutukulidwa

Vestibular canal

Cochlear duct

Tympanic canal