’Yan Adam suna da wani yanayin fahimta na musamman game da lamba uku. Ka yi tunanin labarai da yawa da suka yi amfani da ita, daga The Three Little Pigs zuwa Goldilocks and the Three Bears da The Three Musketeers. Bayanin jama’a da yaƙin neman zaɓe na siyasa suna amfani da ita don tasiri da sauƙin tunawa (“Tsaya, duba kuma saurare”; “Gani shi. Faɗe shi. An gyara”; “Rage, sake amfani, sake sarrafawa”). Sannan akwai tsarin tunani na ilimin halin ɗan adam ko falsafa: Freud da id, ego da superego; sassan uku na kurwa na ɗan adam na Plato; Triniti Mai Tsarki. To, ya zama cewa ilimin jijiyoyi ba shi da kariya daga ciwon uku. A shekara ta 1959 Paul D MacLean ya ƙaddamar da wata sabuwar hanyar tunani game da juyin halitta da aikin kwakwalwa, wanda ya yi wa baftisma “triune” – uku-cikin-ɗaya – samfurin. Nan da nan ya zama ɗaya daga cikin sanannun kuma mafi dawwama ra’ayoyi a ilimin halittar ɗan adam. Tunaninsa shi ne cewa uku daban-daban kwakwalwo suna kwance a cikin kwanyar mu, ɗaya a kan ɗayan, duk suna gwagwarmaya don haifar da ji da tunanin mu. A ciki, a tsakiya, akwai tsohuwar kwakwalwar kadangare, wadda aka ajiye daga kakanni da muke da su tare da dabbobi masu rarrafe. Wannan tana ɗauke da tsoffin yankuna da ke da alhakin rayuwa, suna taimaka mana mu yi farauta da neman abinci, kuma suna motsa sha’awoyin mu na jima’i domin mu haihu. Wani Layer na biyu yana kewaye da na farko, wanda ake kira kwakwalwar dabbobi masu shayarwa. Tana ɗauke da tsarin limbic, wanda ake ɗauka a matsayin wurin da motsin zuciyarmu take. Ya ba dabbobi masu shayarwa damar yin wasa, kula da jinyar ’ya’yansu da sadarwa ta wata hanya mara kyau. Layer na uku kuma na ƙarshe, wanda ke rufe duk wannan kuma ya sa ’yan adam musamman su fi girma, ita ce kwakwalwar “neomammalian”: cortex mai hankali sosai. Wannan, an ba da shawara, yana ba mu ƙwarin gwiwa mafi girma, ikon harshe da ikon yin tunani. A cewar MacLean, ya taimaka wajen kame sha’awoyin mu na farko, irin na kadangare da halayen motsin rai na farko. An yi tunanin halayen ɗan adam sakamakon hulɗa tsakanin duk Layers uku na kwakwalwar triune. Fushin da ya lalace, ayyukan gaggawa da tunanin ɗan gajeren lokaci alamun kwakwalwar kadangare ne ta yi nasara. Ra’ayin motsin rai na dabbobi masu rarrafe “shiga” ya zama sananne sosai har ya shiga cikin duniyar ilimin halin ɗan adam na pop, kasuwanci da taimakon kai, kuma ya zama mai dorewa sosai. Wata ƙaramar masana’antar littattafai, jawabai da horo ta girma a kusa da ra’ayin cewa za ka iya amfani da ƙarfin kwakwalwar neomammalian don kame motsin rai na asali, marasa amfani ko masu lalata. Kwatancin da ke ƙarƙashinsa – na kwakwalwa mai kama da albasa da ta ƙunshi daban-daban strata – yanzu ana ɗaukarsa a matsayin mai ɓatarwa sosai daga masana ilimin jijiyoyi. Yana da sauƙin fahimta, tabbas, kuma yana ba da labari mai jan hankali. Amma juyin halitta ba ya haɗa iyawar tunani masu rarrabuwa cikin tsari kamar haka. MacLean ya gudanar da rarraba halittu masu rai don ƙoƙarin tabbatar da ka’idarsa, amma sakamakon, da fassarar da ya yi su, tun daga lokacin an yi watsi da su sosai. Misali, yanzu an yarda cewa yawancin dabbobi masu rarrafe suna da tsarin limbic na “dabbobi masu shayarwa”, yayin da duk dabbobi masu shayarwa ke nuna siffofin “neomammalian” waɗanda a da ake tunanin sun keɓanta ga “mafi girma” kamar mu. Tare da waɗannan abubuwan lura na jiki, akwai bayanan halayya kuma, tare da yawancin dabbobi “ƙananan” suna da kyau wajen warware matsala, amsa da koyo ta hanyar motsin rai, da sadarwa ta hanyoyi masu rikitarwa. Kamar yadda Guy Leschziner, masanin jijiyoyi mai ba da shawara a asibitin Guy’s da St Thomas na London ya gaya mini: “Ra’ayin sassan kwakwalwa daban-daban suna da ayyuka daban-daban an tabbatar da shi sosai. Duk da haka, kwatanta ’yan adam a matsayin masu Layers kwakwalwa daban-daban, misali ‘kwakwalwar kadangare’ da ke ƙarƙashin ayyukan jiki na asali, ba a tabbatar da shi ta hanyar shaidar juyin halitta ko ilimin jiki ba. Da farko, dabbobi masu shayarwa da masu rarrafe sun rabu da wuri a tsarin juyin halitta. Ko da yake gaskiya ne cewa ayyuka mafi na farko a cikin kwakwalwan mu sun samo asali a farkon rayuwa a duniya, ra’ayin cewa tsarin kwakwalwa uku daban-daban suna tafiyar da sha’awoyin mu na asali, motsin rai, da hankali bi da bi ba ya tsayawa. Lisa Feldman Barrett, farfesa a ilimin halin ɗan adam a Jami’ar Northeastern, wata murya ce ta zamani da ke ƙoƙarin karyata tatsuniyar kwakwalwar kadangare. A ganinta, maimakon yin aiki a matsayin fagen yaƙi tsakanin tsohuwar ilhami, motsin rai, da hankali mai zurfi, kwakwalwa tsari ne mai ƙarfi, haɗaɗɗe wanda manufarsa ita ce kiyaye mu da rai ta hanyar tsinkaya da tsara bukatun makamashin mu. A fannin jijiyoyi da halayya, idan ba tukuna a cikin sani na jama’a ba, ra’ayin cewa dukanmu muna da kwakwalwar kadangare an yi watsi da shi sosai. Duk da haka duk da shaidu masu tarin yawa, da nasarar sabbin tsare-tsare, kwakwalwar triune tana dawwama. Abin mamaki, har yanzu ana koyar da ita sosai a cikin littattafan ilimin halin ɗan adam na gabatarwa (kamar yadda wata kasidar mujalla mai taken “Your Brain Is Not an Onion With a Tiny Reptile Inside” ta nuna). Binciken ya kuma nuna wasu daga cikin haɗarin barin hasashen ba a ƙalubalanci ba, waɗanda suka haɗa da ba wa ɗalibai ƙarya game da yadda juyin halitta ke gudana, da haɓaka ra’ayin cewa ’yan adam suna da keɓaɓɓen ikon ayyukan “hankali” kamar jinkirta biyan buƙata – sadaukar da lada na ɗan gajeren lokaci don riba na dogon lokaci.
To, menene game da samfurin MacLean da ba za mu iya barin shi ba? To, kamar yadda muka gani, mutane da gaske suna ganin suna son uku. Amma watakila akwai fiye da haka. Kwakwalwar triune tana gaya mana labari mai ƙarfafa girman kai game da matsayinmu a duniya: cewa mu ne ainihin kololuwar juyin halitta, muna bambanta da sauran nau’in halittu. Tana sake tabbatar da manyan ra’ayoyi game da ikonmu a kan yanayi, kuma tana ba da labari mai kwantar da hankali game da iyawarmu na hankali, tsari, kusan lissafi. Mu halittu ne masu ba da labari, tabbas, amma wannan labari ne da ke buƙatar sabuntawa – zuwa ɗaya game da yadda muke da yawa da sauran dabbobi, da yadda zato mai sauƙi game da yadda tunaninmu ke aiki kusan ba gaskiya ba ne. Dr Hannah Critchlow masanin jijiyoyi ne kuma marubucin The 21st Century Brain (Torva).
Ƙarin karatu
Seven Deadly Sins na Guy Leschziner (William Collins, £20)
How Emotions are Made na Lisa Feldman Barrett (Pan, £12.99)
Our Brains, Our Selves na Masud Husain (Canongate, £20)
Tambayoyin da ake yawan yi
Tambayoyin da ake yawan yi Shin da gaske akwai Kwakwalwar Kadangare da ke ɓoye ƙarƙashin Hankalinmu
1 Menene kwakwalwar kadangare da kowa ke magana akai
Laƙabi ne ga tsofaffin sassan kwakwalwan mu mafi na farko—musamman brainstem da cerebellum—waɗanda ke gudanar da ayyukan rayuwa na asali kamar numfashi, bugun zuciya da reflexes
2 Shin da gaske akwai kwakwalwar kadangare a cikin kaina
A zahiri a’a Ba ka da kwakwalwar kadangare a cikin kwanyarka Misali ne kawai na tsoffin tsarin atomatik da muke da su tare da dabbobi masu rarrafe da sauran dabbobi
3 Daga ina wannan ra’ayin ya fito
Ya fito daga ka’idar kwakwalwar triune da masanin jijiyoyi Paul MacLean ya gabatar a shekarun 1960 Ya ba da shawara cewa kwakwalwa tana da Layers uku: na dabba mai rarrafe, na dabba mai shayarwa da na ɗan adam
4 To shin ka’idar kwakwalwar triune gaskiya ce
Ba sosai ba Ilimin jijiyoyi na zamani ya yi watsi da ita sosai Kwakwalwa ba ta aiki cikin Layers masu tsari—tana da haɗin kai sosai kuma har yankuna na farko suna da hannu cikin tunani mai rikitarwa
5 Me ya sa mutane har yanzu suna amfani da kalmar kwakwalwar kadangare
Saboda hanya ce mai sauƙi Tana taimakawa bayyana dalilin da ya sa wasu lokuta muke amsa da motsin rai ko ilhami kafin mu yi tunani sosai
6 Menene kwakwalwar kadangare da gaske take sarrafawa
Ayyukan rayuwa na asali: numfashi, bugun zuciya, daidaituwa, martanin yaƙi-ko-gudu, yunwa da reflexes
7 Shin kwakwalwar kadangare tana sa ni yin abubuwa na son kai ko na tashin hankali
Ba ita kaɗai ba Tana amsa barazana da buƙatu amma motsin zuciyarka da tunaninka suna tsara yadda kake amsawa
8 Me ya sa wasu lokuta nakan yi aiki kafin in yi tunani
Saboda hanyoyin kwakwalwa masu sauri na atomatik na iya yin aiki kafin jinkirin tunani da gangan ya fara—musamman a ƙarƙashin damuwa, tsoro ko jin daɗi
9 Shin hankali mai tunani ya bambanta da kwakwalwar kadangare
A’a Suna da alaƙa mai zurfi Tunani yana amfani da bayanai daga tsarin motsin rai da rayuwa kuma su biyun suna yin tasiri a kan juna koyaushe
10 Zan iya sarrafa kwakwalwar kadangare ta
Ba za ka iya kashe ta ba amma za ka iya sarrafa martaninka ta hanyar sani, numfashi, tsayawa da aiki
11 Menene wasu misalai na yau da kullum na kwakwalwar kadangare tana aiki
Yin tsalle lokacin da wani abu ya motsa da sauri kusa da fuskarka, yin tsalle da ƙarar murya, jin zuciyarka tana bugawa kafin jawabi ko yin fushi da wani lokacin da kake cikin damuwa
