IINKCUKACHA: Isifundo sibonisa ukuba indalo yokuqinisa - iswekile- inokubangela iziphumo ezifanayo njengesiyobisi: ukuxhomekeka, ukunyamezelana, kunye nokurhoxa. Iswekile ibangele utshintsho ekusebenzeni kwe-dopamine-Oko kukuthi, kwi-dopamine dysregulation.
Iigundane zasela isiselo esinxilisayo kunesiqhelo emva kokuba kunqunyulwe iswekile, nto leyo ebonisa ukuba ukungxwelerha kuye kwenza utshintsho kwindlela yokusebenza kwengqondo.
I-ScienceDaily (Dec. 11, 2008)-Isazinzulu seYunivesithi yasePrinceton siza kuveza ubungqina obutsha namhlanje Ukubonakalisa ukuba iswekile ingayinto enokulutha, ukusebenzisa amandla ayo ngaphezulu kweengqondo zezilwanyana zelebhu ngendlela efanayo neziyobisi ezininzi zokuxhatshazwa.
Unjingalwazi uBart Hoebel kunye neqela lakhe kwiCandelo lezeMpilo yezeengqondo kunye nePrinceton Neuroscience Institute bebefunda iimpawu zokulutha iswekile kwiigundane kangangeminyaka. Kude kube ngoku, iigundane eziphantsi kwesifundo zidibene nezinto ezimbini kwezi zinto zintathu. Babonise indlela yokuziphatha yokuziphatha eyonyukayo emva koko babonisa iimpawu zokurhoxa. Izilingo zakhe zangoku zibambe umnqweno kwaye iphinde ibuyele ukugcwalisa umfanekiso.
"Ukuba ukuzinkcinkca ngeswekile ngokwenene kuyindlela yotywala, kufanele ukuba kubekho iziphumo ezihlala ixesha elide kwingqondo yeziyobisi ezineswekile," utshilo uHoebel. "Ukulangazelela nokuphinda ubuye yinto ebaluleke kakhulu kubukhoboka, kwaye sikwazile ukubonisa iindlela zokuziphatha kwiigundane ezityisa iswekile ngeendlela ezininzi."
Kwintlanganiso yonyaka yeKholeji yaseMelika yeNeuropsychopharmacology eScottsdale, eAriz., UHoebel uya kunika ingxelo malunga neenguqu ezinzulu zokuziphatha kwiigundane ethi, ngeemeko zovavanyo, ziqeqeshelwe ukuba zixhomekeke kumadosi aphezulu eswekile.
"Sinesethi yokuqala yezifundo ezibanzi ezibonisa isindululo esomeleleyo sokulutha iswekile kwiigundane kunye nendlela enokubangela oko," utshilo uHoebel. Iziphumo ekugqibeleni zinokuba nefuthe kunyango lwabantu abanengxaki yokutya, utshilo.
Izilwanyana zaselebhu, kuvavanyo lukaHoebel, ezazingavunywanga iswekile kangangexesha elide emva kokufunda ukuzinkcinkca ngotywala zisebenze nzima ukuyifumana xa iphinde yabuyiselwa kubo. Batya iswekile engaphezulu kunangaphambili, becebisa ngenkanuko kunye nokuziphatha kwakhona. Inkuthazo yabo yeswekile ikhulile. Kule meko, ukungabinakho ukwenza ukuba intliziyo ikhule ithande, utshilo uHoebel.
Iigundane zisela utywala kakhulu kunesiqhelo emva kokuba ukunqunyulwa kweswekile yabo, kubonisa ukuba isimilo sokuzinkcinkca sabangela utshintsho ekusebenzeni kwengqondo. Le misebenzi isebenze njenge "ndlela yokungena" kwezinye iindlela zokuziphatha ezonakalisayo, ezinje ngokwanda kotywala. Kwaye, emva kokufumana idosi ye-amphetamine ngokwesiqhelo ubuncinci kakhulu ayinampembelelo, baba namandla kakhulu. Ukwanda kobuntununtunu kwi-psychostimulant sisiphumo seengqondo esihlala ixesha elide esinokuba yinto yokulutha, utshilo uHoebel.
Idatha eza kuboniswa nguHoebel ifumaneka kwiphepha lophando elingeniswe kwiJenali yoKutya. Ukutyelelwa ngabaphandi uNicole Avena, ofumene i-Ph.D yakhe. besuka ePrinceton e2006, kunye noPedro Rada ovela kwiDyunivesithi yaseLos Andes eVenezuela babhale iphepha kunye noHoebel.
U-Hoebel unomdla kwiinkqubo zobuchopho ezilawula ukuthanda ukutya kunye nobunzima bomzimba kuba wayengumfundi onesidanga kwiYunivesithi yaseHarvard efunda kunye neBF Skinner eyaziwayo. Kwi-faculty yePrinceton ukusukela kwi1963, uye waqhuba izifundo kwimivuzo yengqondo yokutya. Kwiminyaka elishumi edlulileyo, uHoebel ukhokele umsebenzi ngoku ogqibe umfuziselo wesilwanyana sokuba likhoboka leswekile.
U-Hoebel ubonakalisile ukuba iigundane zitya iswekile eninzi xa zilambile, into eyichaza njengokubanjiswa kweswekile, yenzeka kwiinguqu kwimithambo-luvo ebonakala ngathi ilingisa ezo ziveliswa zizinto zokuphathwa gadalala, kubandakanya icocaine, morphine kunye nicotine. Iswekile yenza ukuba utshintsho kwindlela yokuziphatha, nayo. "Kwiimodeli ezithile, ukuzinkcinkca ngeswekile kubangela iziphumo ezihlala ixesha elide kwingqondo kwaye kwandise ukutyekela kokuthatha ezinye iziyobisi zokuxhatshazwa, ezinje ngotywala," utshilo uHoebel.
U-Hoebel kunye neqela lakhe bafumanise ukuba kukhutshwa ikhemikhali eyaziwa ngokuba yi-dopamine kwingingqi yengqondo eyaziwa ngokuba yi-nucleus accumbens xa iigundane zilambile zisela isisombululo seswekile . Olu phawu lwekhemikhali lucingelwa ukuba lubangela ukukhuthaza kunye, kwaye nokuphindaphinda, ukulutha.
Abaphandi baqhuba izifundo ngokunqanda iigundane zokutya kwabo ngelixa iigundane zilele kunye neeyure ezine emva kokuvuka. "Kancinci njengokuphosa isidlo sakusasa," utshilo uHoebel. Ngenxa yoko, bakhawuleza batye i-chow kwaye basele amanzi amaninzi aneswekile. ” Wongeze wathi, "Yiloo nto ibizwa ngokuba kukuzinkcinkca ngotywala- xa usitya kakhulu ngaxeshanye- kule meko bazinkcinkca ngesisombululo se-10 sepesenti, esinjengesiselo esinxilisayo."
Iigundane ezilambe zilambatha iswekile zivusa ugqirha wazo. Emva kwenyanga, ulwakhiwo lobuchwephesha bezi mpawu lutshintshela kwinqanaba le-dopamine, libonisa inani elincinci lohlobo oluthile lwe-dopamine receptor kunokuba babenalo kunye nee-receptor ezingaphezulu kweopioid. Ezi nkqubo ze-dopamine kunye ne-opioid zibandakanyeka kwisishukumiso kunye nomvuzo, iinkqubo ezilawula ukufuna kunye nokuthanda into. Utshintsho olufanayo lukwabonwa kwiimpawu zegundane kwi-cocaine kunye ne-heroin.
Kuvavanyo, abaphandi baye bakwazi ukwenza imiqondiso yokurhoxa kwizilwanyana zaselebhu ngokususa iswekile yazo. Amanqanaba engqondo eempuku zedopamine yehlile kwaye, ngenxa yoko, babonisa uxinzelelo njengophawu lokurhoxa. Amazinyo eempuku ahlahlakazekile, kwaye izidalwa zazingakulungelanga ukuphuma ziye kwingalo evulekileyo ye-maze yazo, zikhetha ukuhlala kwindawo yetonela. Ngokwesiqhelo iigundane ziyathanda ukuphonononga imeko-bume yazo, kodwa iigundane ekurhoxisweni kweswekile zazinexhala lokujonga.
Iziphumo zifumene umdla, utshilo uHoebel, kodwa uphando oluthe kratya luyafuneka ukuqonda iziphumo. Esona sicelo sisebenzayo ebantwini siya kubakho kwicandelo leengxaki zokutya.
"Kubonakala ngathi kunokwenzeka ukuba uhlengahlengiso lobuchopho kunye neempawu zokuziphatha ezibonwa kwiigundane zinokwenzeka kwabanye abantu abanesifo sokutya kakhulu okanye i-bulimia," utshilo uHoebel.
“Umsebenzi wethu ubonelela ngonxibelelwano phakathi kokuchazwa ngokwesiko kokusetyenziswa kweziyobisi, ezinje ngeziyobisi, kunye nokukhula kweminqweno engaqhelekanga yezinto zendalo.
Olu lwazi lunokusinceda ukuba siqulunqe iindlela ezintsha zokuchonga nokunyanga iziyobisi ebantwini. ”
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