I-DMN kanye nokuxhumana okusebenzayo
Ukufaneka kwemifanekiso ye-resonance magnetic (fMRI) isivumela ukuba senze izingqinamba ekusebenzeni kobuchopho kubantu abaphilayo abesebenzisa izithombe eziphoqelelayo. Ngokomunye, uye wasivumela ukuba senze imibono ebalulekile ekusebenzeni komqondo wobuchopho ngokwemvelo, kufaka phakathi inethiwekhi yemodi yokuzenzakalelayo. Ukuze uqonde amanethiwekhi anjalo, noma kunjalo, isizinda esithile ekuxhumaneni okusebenzayo kuyadingeka kuqala.
Kuyini Ukuxhumana Okusebenzayo MRI?
Ucwaningo oluningi lwe-fMRI lwenziwa ngenkathi isiguli senza umsebenzi othile ngenkuthalo. Isibonelo, uma bephoqa inkinobho ngesandla sabo sokunene, ungase ubone kamuva ingxenye ye-hemisphere yesokunxele eduze kwe-motor cortex ukukhanya ngaleso sikhathi.
Enye indlela ukubuka ubuchopho ngenkathi umvolontiya ocwaningo engenzi lutho nhlobo ku-scanner - nje ulale lapho. Leli khono ngezinye izikhathi libizwa ngokuthi "isimo sokuphumula" i-fMRI.
Ngesikhathi silala lapho, izindawo ezihlukene zobuchopho zinomsebenzi oscillatory, okusho amagagasi kagesi ahlobene nesignali ye-MRI. Ngezinye izikhathi, lamagagasi ahlangene nomunye nomunye, okusho ukuthi ahlasela ama-high and lows of the waveform ngesikhathi esifanayo. Kancane njengokungathi babengamalungu ahlukene we-orchestra adlala ingoma efanayo yomculo ngenkathi elandela umqhubi ofanayo. Kuthiwa izindawo ezimbili ezinjalo zixhunywe ngokusebenza.
Ukuxhumana okusebenzayo akumelwe kulinganiswe ngokuphumula. Imisebenzi efana nokulalela into ebalulekile ingashintsha amaphethini wokuxhumana okusebenzayo kuwo wonke ubuchopho.
Ukuxhumana okusebenzayo akusho ukuthi izindawo ezimbili zobuchopho zixhunywe ngokuqondile nangokomzimba. Isibonelo, izindawo ezimbili zobuchopho ezihlukene zingase zibe kude kakhulu, kepha bobabili bathola izibonakaliso ezivela esifundeni sobuchopho obuphakathi njengethalamus.
Lezi zingase zisebenze ngokuxhumekile uma izimpawu zabo ziyi-synchrony.
Ukwethulwa kwenethiwekhi yendlela yokuzenzakalelayo
Kule minyaka eyishumi edlule, ukunakekelwa okukhudlwana kuye kwakhokhwa kulokhu kuhlanganiswa komsebenzi njengendlela yokuthola amanethiwekhi ebuchosheni ahlobene nemisebenzi ethile, kuhlanganise nokuphumula kuphela. Enye yezinethiwekhi ezivelele okuzoxoxwa ngayo inethiwekhi yokuzenzakalelayo yenethiwekhi.
Igama elithi "imodi yokuzenzakalelayo" lasetshenziswa okokuqala nguDkt. Marcus Raichle ngo-2001 ukuchaza umsebenzi wokuphumula wengqondo. Kuye kwaphawulwa ngaphambili ukuthi ubuchopho "bokuphumula" basebenzisa amandla angaphansi kancane kunokuba ubuchopho benze umsebenzi "osebenzayo," okuphakamisa ukuthi mhlawumbe ubuchopho "abuphumuli" kakhulu uma kushintsha uhlobo lomsebenzi lapho lusebenza khona uhlanganyele.
Inethiwekhi yemodi yokuzenzakalelayo (DMN) ihilela ama-oscillations aphansi-ngokuhamba okukodwa ngomzuzwana. Inethiwekhi iyasebenza kakhulu uma ubuchopho buphumula. Uma ubuchopho buqondiswa kumsebenzi noma umgomo, inethiwekhi engalungile ivimbela.
Kungenzeka, empeleni, kube nenethiwekhi engaphezu kweyodwa yenethiwekhi yokuzenzakalelayo-lokho esikubiza ngokuthi i-DMN ingaba yiqoqo lamanethiwekhi amancane, ngalinye lizinikezelwe okuthile okuhlukile kunomunye. Noma kunjalo, izindawo ezithile zobuchopho manje zivame ukuqondwa njengengxenye ye-DMN.
Yiziphi izingxenye zobunongo eziku-DMN?
Izindawo zobuchopho ezifakwe kwinethiwekhi yemodi yokuzenzakalelayo zihlanganisa i-lobe yesikhashana yangaphakathi, i -prefrontal cortex yangaphakathi , kanye ne-cortex yangemva kwe-cingulate, kanye ne-ventral precuneus kanye nezingxenye ze-cortex ye-parietal. Zonke lezi zifunda ziye zahlotshaniswa nesinye isici somcabango wangaphakathi. Isibonelo, i-lobe yesikhashana yangaphakathi ihlotshaniswa nenkumbulo . I-cortex ye-prefrontal yangaphakathi ihlotshaniswe nenkolelo yengqondo, ikhono lokubona abanye njengabacabanga nemicabango efana neyakho. I-posting cingulate yokucatshangelwa kucatshangwa ukuthi ihlanganisa ukuhlanganisa izinhlobo ezahlukene zemicabango yangaphakathi.
I-neurons yama-mirror iphindelwe futhi ukuba ihlanganyele ne-DMN.
Yenzani i-DMN?
Ngenxa yokuthi inethiwekhi yemodi yokuzenzakalelayo iyasebenza ngokuphumula futhi ngenxa yezakhiwo ezihilelekile, abanye abantu baye bafakazela ukuthi kuhlotshaniswa nomcabango ozayo, kufaka phakathi imisebenzi efana nokwehla noma ukubuyisa izinkumbulo. Abanye baye basikisela ukuthi, lo msebenzi ungase uhlotshaniswe nezinqubo zomzimba ezingahambisani nanoma imuphi umsebenzi - ngisho nokuphumula - nakuba le mbono ibonakala ingekho.
Izinguquko kwinethiwekhi yemodi yokuzenzakalelayo ziye zaxhunyaniswa nenani elibanzi lezifo ezahlukene, kuhlanganise nesifo se-Alzheimer, i-autism, i-schizophrenia, isifo se-bipolar, isifo sokucindezeleka ngemuva kokucindezeleka, nokucindezeleka, nokuningi. Izifo zingabangela umsebenzi omncane kakhulu noma okuningi, futhi ngezinye izikhathi idatha ihlukahluka ngokuthi yiyiphi eyenzeka ngempela. Kungakhathaliseki ukuthi lokhu kubonisa ukungaqondi kahle kwesifo, le nqubo, noma kokubili ingavamile.
Enye yezingqinamba eziye zavela mayelana ne-DMN ukuthi ukuguqulwa ngaphakathi kuyo kubonakala kungacacile kakhulu - yimuphi ukusebenzisa isilinganiso uma ingakutshelisi ukuthi iyiphi inkinga? Abanye baye bakhathazeka uma inethiwekhi ingumqondo onamandla, nakuba njengoba ucwaningo lubamba ubuciko bokuphila kwe-DMN kuba nzima ukubuza.
Amanye amanethiwekhi, afana nalawo ahlotshaniswa ukunakekelwa, umbono, nokuzwa, nawo achazwe. Ngenkathi izinzuzo zezokwelapha zalezi zinethiwekhi zihlala zingacacile, zingabonakalisa ushintsho olubalulekile endleleni esicabanga ngayo ngobuchopho, futhi ubani ongasho ukuthi ukucabanga okunjalo kuzosithatha esikhathini esizayo?
> Imithombo:
> Buckner, RL; U-Andrews-Hanna, JR; I-Schacter, i-DL (2008). "Inethiwekhi Ye-Brain Default Network: Anatomy, Function, and Perlevance to Disease". Amanothi we-New York Academy of Sciences 1124 (1): 1-38.
> Fair, DA; Cohen, AL; I-Dosenbach, i-NUF; I-Church, JA; Miezin, FM; I-Barch, i-DM; URaichle, ME; Petersen, SE et al. (2008). "Izakhiwo ezikhulayo zenethiwekhi yokuzenzakalelayo yobuchopho". Izinqubo ze-National Academy of Sciences 105 (10): 4028-32.
> Raichle, uMarcus E .; Snyder, Abraham Z. (2007). "Imodi ezenzakalelayo yokusebenza kobuchopho: Umlando omfushane womqondo oguqukayo". I-NeuroImage 37 (4): 1083-90.