Too yawa neurons ganimar da Memory

Too Many Neurons Spoil the Memory

New bincike bayyana salon salula sunadaran da abin da memory-shigar neuronal networks fito fili


Powered by Guardian.co.ukWannan labarin mai taken “Too yawa neurons ganimar da memory” aka rubuta ta hanyar Mo Costandi, domin theguardian.com a ranar Jumma'a 12th Fabrairu 2016 15.15 UTC

Ka faɗa mini inda zauna da tunani, manta har ka kira su fita? Ka faɗa mini inda zauna qawar old, da kuma inda tsoho son, Kuma a lõkacin da zã su sabunta sake, da kuma dare na gushewa da, Wannan na iya kẽta sau da sarari m m, da kuma kawo ta'aziya cikin wani m baƙin ciki, kuma a dare na jin zafi? Ina goest ka, Ya tunani? To abin da m ƙasar ne ka gudu? Idan ka returnest zuwa yanzu lokacin da cũta, Za ka kawo ta'aziya a ka fuka-fuki, kuma dews da zuma da balm, Ko guba daga cikin hamada wilds, daga idanun hãsada?

A cikin almara waka, Wahayi na matan Albion, William Blake abubuwan al'ajabi game da yanayin ƙwaƙwalwar, da ikon tunani safarar mu mu m sau da wuraren, da iko motsin zuciyarmu, biyu tabbatacce kuma korau, cewa mu tunaninsu iya samar. The waka ƙunshi tambayoyi da zama sosai pertinent yau, kamar abin da ya faru da mu dogon batattu tunanin, kuma ta yaya muka mai da su?

Fiye da biyu ƙarni daga baya, da sunadaran da memory ajiya da kuma gyara su ne mafi intensively karatu mamaki a cikin kwakwalwa sciences. An yadu yi imani da cewa memory samuwar shafi da tabbatarwa daga sadarwa tsakanin sparsely rarraba networks na neurons a kwakwalwa tsarin da ake kira hippocampus, da kuma cewa m gyara shafi reactivation na wannan neuronal was. Kuma duk da haka, neuroscientists har yanzu fafitikar amsa Blake ta tambayoyi shakka.

Yanzu, wata tawagar masu bincike, a Jami'ar Geneva sanya wani muhimmanci gaba a fahimtar da na tsarin jijiya sunadaran muhimmi memory samuwar. Amfani da jihar-of-da-art hanya da ake kira optogenetics, suna nuna yadda neuronal was cewa encode tunanin fito fili, bayyana cewa was dauke da yawa neurons - ko kuma 'yan - rage memory gyara.

optogenetics sigar musamman m dabara da ya shafi gabatar da algal sunadarai kira channelrhodopsins (ChRs) cikin neurons. Wannan ya fassara sel m zuwa ga haske, irin wannan cewa ajali kungiyoyin cikinsu za a iya kunna ko kashe, ta yin amfani da hatsaisai na Laser haske tsĩrar a cikin kwakwalwa via Tantancewar zaruruwa, a kan wani timescale na ƴan daƙiƙa.

A cikin 'yan shekarun, masu bincike sun yi amfani da optogenetics to Label hippocampal neurons cewa zama aiki a lokacin memory samuwar a cikin linzamin kwamfuta kwakwalwa, da kuma yi amfani da labeled was a hanyoyi. A cikin wannan hanya, za su iya reactivate guda was to sa memory gyara; canjawa tsõro tunanin ko kashe; maida korau tunanin cikin m wadanda, ko mataimakin versa; har ma da implant gaba ɗaya ƙarya tunanin cikin kwakwalwarmu da mice.

The sabon bincike, jagorancin Pablo Mendez da marigayi Dominique Muller, wanda takaici mutu a cikin wani hadarin gliding a watan Afrilu na shekarar bara, gina a kan wannan a baya aiki. Suka halitta genetically aikin injiniya mice bayyana Tar a granule Kwayoyin a gefe daya daga cikin kwakwalwa, a cikin dentate yankin na hippocampus. Granule Kwayoyin suna da manufa neurons a cikin wannan yankin na hippocampus, wanda aka yi zaton ya zama m for hippocampal ayyuka kamar memory da na sarari navigation. Sai suka sanya dabbobi a cikin manyan cages, kyale wasu daga cikinsu don gano sabon yanayi. A halin yanzu, su optogenetically kunna bazuwar granule Kwayoyin a wasu daga cikin mice, amma ba wasu.

Hippocampal granule Kwayoyin bayyana Channelrhodopsin (a ja).
Hippocampal granule Kwayoyin bayyana Channelrhodopsin (a ja). image: Pablo Mendez

A lõkacin da suka dissected da yayi nazari da dabbobi "tarar da kwakwalwarmu 45 minutes daga baya, da masu bincike gano sarari bincike evoked aiki a was na hippocampal neurons, kamar yadda m da matakan cFos, a abin da ake kira 'nan da nan wuri' gene da aka kunna sauri a lokacin da neurons fara wuta. mahimmanci, mice yarda su gano su cages da hakan lambobi daga cFos-bayyana granule Kwayoyin fiye da wadanda bar a cikin gida cages ga duration na gwaji, da kuma waɗanda suke samu optogenetic ruri lokacin bincike da muhimmanci mafi girma lambobi daga cFos-positive neurons daga waɗanda cewa ba.

Wannan ya nuna cewa sarari bincike evokes aiki a was na dentate granule Kwayoyin, da kuma cewa da ka musanyãwa na ayyuka na wadannan networks da optogenetic ruri qara girman da was, ko yawan Kwayoyin cikin su.

Amma bai sabawa girman da was da wani sakamako a kan hali? Don gano, Mendez da takwarorinsa sanya mice bayyana Tar a hippocampi cikin wani keji, kuma ba su da yawa m lantarki kona. Tare da maimaita wannan magani, da mice sauri koyi tsoron keji, da sauri daskare up lokacin da ya koma a cikinta, har a lokacin da suke ba da more kona.

wannan lokaci, da masu bincike optogenetically kara kuzari bazuwar granule Kwayoyin a wasu daga cikin mice, amma ba wasu, a lokacin horo, domin ya kara girman da neuronal gungu cewa encodes da tsõro memory. Wadannan mice nuna m daskarewa hali a lokacin da ya koma zuwa ga wannan keji fiye da wasu da suka karbi wani ruri. Amma ruri kuma Ya halitta wucin gadi tsoro tunanin, irin wannan cewa dabbobi froze up a wasu yanayi, kuma.

Hanawa daga bazuwar granule Kwayoyin da wannan sakamako, bayar da shawara cewa kawai musanyãwa yawan neurons a gungu ya tsoma baki tare da dabbobi "ikon tuna da tsõro tunanin. Wadannan binciken ne daidai da wadanda daga baya binciken, wanda ya hada da nuna cewa inhibiting ko haramta motsa granule cell aiki impairs kunsa ilmantarwa.

Don gane dalilin da ya sa wannan zai zama, da masu bincike ya yi wani jerin gwaje-gwajen, ta yin amfani da microelectrodes rikodin na ayyuka na neurons a yanka na hippocampal nama. Wadannan gwaje-gwajen ya nuna cewa optogenetic ruri daga granule Kwayoyin samar da wani robust amsa a makwabciyar interneurons, wanda saki mai hanawa neurotransmitter Gaba.

Kamar wancan, da harbe-harben da granule Kwayoyin kaiwa mai hanawa interneurons, wanda dampen m granule Kwayoyin kuma hana su daga shiga gungu. A cikin wannan hanya, interneurons bayyana don daidaita sabuwar-kafa tunanin da gudãnar da lambar kuma rarraba granule Kwayoyin hannu a tsarinsa tunanin. Kunna ko silencing bazuwar granule Kwayoyin kofi wannan tsari da kuma ya musanya masa a yawan granule Kwayoyin, wanda zai iya yi da sabon tunanin m.

"A cikin wannan binciken, mu yi amfani da sauki nau'i na memory, ƙwaƙwalwar wani sarari mahallin, amma kalubale na nazarin yadda more hadaddun abubuwan da ake haddace, da kuma yadda kwakwalwa ke hulda da ajiya na mahara abubuwan,"Ya ce Mendez. "Fahimtar wadannan tambayoyi zai taimaka mana mu fahimci haddi a cikin kwakwalwa ta ajiya iya aiki."

reference

Stefanelli, T., et al. (2016). Hippocampal Somatostatin Interneurons Control girman Neuronal Memory was. Neuron, 89: 1-12. doi: 10.1016/j.neuron.2016.01.024 [Abstract]

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