Ukulala—Ingabe Kuyisenzo Sokunethezeka Noma Kuyadingeka?

KWABANYE abantu, ukulala kuwukuchitha isikhathi. Njengoba behlala bematasa nsuku zonke kwezebhizinisi futhi bezijabulisa nabangane, balala kuphela uma sebekhathele beyingcuba. Ngokuphambene, abanye, ngemva kokuqwasha izinsuku zilandelana, bangenza noma yini ukuze nje bakwazi ukulala kahle.

Kungani abanye bekuthola kunzima kangaka ukulala, kuyilapho abanye bekuthola kunzima ukuxosha ubuthongo? Ingabe kufanele sibheke ukulala njengesenzo sokunethezeka noma njengento edingekayo? Ukuze siphendule le mibuzo, kudingeka siqonde ukuthi kwenzekani lapho silele.

Impicabadala Yokulala

Ukuthi yini ngempela eyenza umuntu alale azumeke kuseyimpicabadala. Nokho, abacwaningi baye bathola ukuthi ukulala kuyinqubo eyinkimbinkimbi elawulwa ubuchopho futhi elandela iwashi lomzimba lamahora angu-24.

Njengoba sikhula, imikhuba yethu yokulala iyashintsha. Usana lulala izikhawu ezimfushane ezihlanganisa ingqikithi yamahora angu-18 ngosuku. Ochwepheshe bezifo zokulala bathi nakuba kubonakala sengathi abanye abantu abadala badinga ukulala amahora amathathu nje kuphela, abanye badinga amahora ayishumi.

Ucwaningo lwamuva nje luye lwabonisa ukuthi ukuhlukahluka kwamawashi emizimba yethu kuyimbangela eyenza enye intsha ikuthole kunzima ukuvuka ekuseni. Kubonakala sengathi iwashi lomzimba lihamba ngokushesha lapho umuntu esathomba, okwenza intsha ifune ukwephuza ukulala futhi yephuze ukuvuka. Ukwephuza ukulala ngale ndlela kuvamile futhi kuyaphela lapho umuntu esecela eminyakeni engamashumi amabili.

Iwashi lethu lomzimba lilawulwa amakhemikhali, amaningi awo asetholakele kakade. Elinye lawo i-melatonin, i-hormone okucatshangwa ukuthi ibangela ukozela. I-melatonin ikhiqizwa ubuchopho, futhi abanye ososayensi bakholelwa ukuthi iyona ebangela ukuba isimiso somzimba sokugaya ukudla sitotobe ngaphambi kokuba umuntu azumeke. Njengoba i-melatonin ikhiqizwa, izinga lokushisa komzimba nokugeleza kwegazi eliya ebuchosheni kuyehla, kanti nemisipha yethu iyathamba kancane kancane. Kube sekwenzekani njengoba umuntu esehlela ezweni eliyimpicabadala lakwabuthongo?

‘Umondli Omkhulu Ongokwemvelo’

Cishe emahoreni amabili ngemva kokuzumeka, amehlo ethu aqala ukunyakaza ngokushesha. Ukubona lokhu kwenza ososayensi bahlukanisa ukulala kwaba izigaba ezimbili eziyisisekelo: i-REM (rapid eye movement) kanye ne-non-REM. Isigaba se-non-REM singahlukaniswa ngezigatshana ezine zamazinga okuzumeka aqhubekayo. Lapho umuntu elele zwí, isigaba se-REM senzeka izikhathi eziningana, sishintshana nese-non-REM.

Ngokuvamile siphupha phakathi nesigaba se-REM. Izicubu zomzimba nazo ziphumula ngokuphelele, okwenza ukuthi umuntu obelele avuke ezizwa eqabulekile. Ngaphezu kwalokho, abanye abacwaningi bakholelwa ukuthi ulwazi umuntu asanda kuluthola lugxila enkumbulweni isikhathi eside phakathi nalesi sigaba sokulala.

Lapho sesizumekile (phakathi nezigaba 3 no-4 ze-non-REM), umfutho wethu wegazi nokushaya kwenhliziyo kuyehla, okwenza isimiso sokujikeleza kwegazi siphumule kusize nokunqanda izifo zenhliziyo. Ngaphezu kwalokho, ama-hormone okukhula akhiqizwa kakhulu phakathi nesigaba se-non-REM, enye intsha ikhiqiza ama-hormone okukhula aphindwe ngaphezu kwezikhathi ezingu-50 ebusuku kunasemini.

Kubonakala sengathi ukulala kuthinta nesifiso sethu sokudla. Ososayensi baye bathola ukuthi empeleni njengoba kwasho uShakespeare, ukulala “kungumondli omkhulu edilini lokuphila.” Ubuchopho bethu bubheka ukungalali kahle njengophawu lokuthi umuntu ulambile. Uma silele, umzimba wethu ukhiqiza i-leptin, i-hormone ngokuvamile etshela umzimba ukuthi sisuthi. Uma sephuza ukulala, umzimba wethu ukhiqiza i-leptin encane, okusenza sizizwe silambile. Ngakho ukuzincisha ubuthongo kungaholela ekudleni kakhulu, kona okungaholela ekukhuluphaleni.—Bheka ibhokisi elithi “Isihlwathi Sasemini Yantambama,” ekhasini 13.

Kubalulekile Empilweni

Kodwa akugcini lapho. Ukulala kwenza kube lula ngomzimba wethu ukuba ugaye izinhlayiya okuthiwa zinengxenye ekugugeni kwamangqamuzana futhi zibangele ngisho nomdlavuza. Ocwaningweni lwamuva olwenziwe i-University of Chicago, izinsizwa ezingu-11 eziyimiqemane zavunyelwa ukuba zilale amahora amane kuphela ngosuku izinsuku eziyisithupha. Ekupheleni kwaleyo nkathi, amangqamuzana azo omzimba ayesebenza njengawabantu abaneminyaka engu-60 ubudala, kanti izinga likashukela egazini lalifana nelomuntu onesifo sikashukela! Ukuzincisha ubuthongo kuthinta nokukhiqizwa kwamangqamuzana amhlophe egazi ne-hormone i-cortisol, okwenza umuntu angenwe izifo ezithathelwanayo nezenhliziyo.

Akungabazeki ukuthi ukulala kubalulekile ukuze sibe nomzimba nengqondo ephilile. Ngokusho komcwaningi uWilliam Dement, owasungula isikhungo sokuqala sokucwaninga ngezifo zokulala, eStanford University, e-U.S.A., “ukulala kubonakala kuyinkomba ebaluleke kakhulu yokuthi uzophila isikhathi eside kangakanani.” UDeborah Suchecki, umcwaningi esikhungweni sezifo zokulala eSão Paulo, eBrazil, uthi: “Ukube abantu bebazi ukuthi kwenzekani emzimbeni oncishwe ubuthongo, bebeyoshintsha umqondo ngokuthi ukulala kuwukuchitha isikhathi noma okwamavila.”—Bheka ibhokisi elingenhla.

Kodwa ingabe konke ukulala kuyawuvuselela umzimba? Kungani abanye abantu belala ubusuku bonke kodwa baqhubeke bezizwa bekhathele? Isihloko esilandelayo sizokusiza ukuba ubone ezinye zezifo eziyinhloko zokungalali, sichaze nendlela ongaqinisekisa ngayo ukuthi ulala zwí.

[Ibhokisi/Isithombe ekhasini 13]

Imiphumela Yokungalali Ngokwanele

IMIPHUMELA YESIKHASHANA

◼ Ukozela

◼ Ukuguquguquka kwemizwelo

◼ Ukukhohlwa isikhashana

◼ Ukuphelelwa ikhono lokusungula, ukuhlela nokufeza izinto ezithile

◼ Ukuhluleka ukugxilisa ingqondo

IMIPHUMELA YESIKHATHI ESIDE

◼ Ukukhuluphala

◼ Ukuguga ngaphambi kwesikhathi

◼ Ukukhathala

◼ Ingozi enkulu yokungenwa yizifo ezithathelwanayo, isifo sikashukela, izifo zenhliziyo nezifo zesisu

◼ Ukukhohlwa okungamahlalakhona

[Ibhokisi ekhasini 13]

ISIHLWATHI SASEMINI YANTAMBAMA

Wake wazizwa wozela ngendlela engalawuleki ngemva kokudla kwasemini? Lokhu akulona ngempela uphawu lokuthi unenkinga yokungalali ngokwanele. Kungokwemvelo ukozela ntambama ngenxa yokwehla kwezinga lokushisa komzimba. Ngaphezu kwalokho, ososayensi basanda kuthola iprotheni okuthiwa i-hypocretin, noma i-orexin, ekhiqizwa ebuchosheni futhi esigcina siphapheme. I-hypocretin ihlangene ngani nokudla?

Uma sidla, umzimba ukhiqiza i-leptin esenza sicabange ukuthi sisuthi. Kodwa i-leptin ithiya ukukhiqizwa kwe-hypocretin. Ngamanye amazwi, uma kune-leptin eningi ebuchosheni, i-hypocretin iba ncane, bese sizizwa sozela kakhulu. Mhlawumbe yilokho okwenza ukuba kwamanye amazwe abantu bathathe isihlwathi—okuyikhefu lokuba abantu bathi ukulala kancane.

[Igrafu ekhasini 12]

(Ukuze ubone ukuthi indaba ihlelwe kanjani, bheka encwadini)

IZIGABA ZOKULALA

Ishadi elenziwe laba lula

Izigaba Zokulala

Uphapheme

I-REM

I-non-REM

Ukulala ube ungazumekile 1

2

3

Ukulala uzumeke zwí 4

1 2 5 6 7 8

Amahora Okulala