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Neuroscientist Antonio Damasio proposed that gut feelings, such as a knot in the stomach or a racing pulse, are not mere side effects of emotion: the brain uses them to steer decisions, especially when the outcome is uncertain. He called these bodily signals somatic markers.

Antonio Damasio, somatic marker hypothesis

MindScience

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Damasio set out the idea in his 1994 book Descartes' Error. It grew from patients with damage to the ventromedial prefrontal cortex, the part of the frontal lobes just above the eyes. They kept their intelligence and knew right from wrong, yet made ruinous choices in real life, as if the bodily warning that says 'this is a bad idea' had gone quiet. In a card game built to test this, the Iowa Gambling Task, healthy players began to sweat slightly before reaching for the risky decks, before they could say why those decks were bad; the patients showed no such signal. The theory remains influential but debated: critics argue it is still unclear whether bodily signals drive choices or simply accompany them.

Türkçe oku
Nörobilimci Antonio Damasio'ya göre mide düğümlenmesi ya da hızlanan nabız gibi bedensel hisler duygunun basit bir yan ürünü değildir: beyin, özellikle sonucun belirsiz olduğu durumlarda kararlarını bu sinyallerle yönlendirir. Damasio bu bedensel işaretlere “somatik belirteç” adını verdi.

Damasio bu fikri 1994 tarihli Descartes'ın Yanılgısı kitabında ortaya koydu. Fikir, beynin ön lobunda, gözlerin hemen üstündeki bölgede (ventromedial prefrontal korteks) hasar bulunan hastalardan doğdu. Bu hastaların zekâsı yerindeydi, doğruyu yanlıştan ayırabiliyorlardı; ama gerçek hayatta yıkıcı kararlar veriyorlardı. Sanki “bu kötü bir fikir” diye uyaran bedensel sinyal susmuştu. Bunu sınamak için geliştirilen Iowa Kumar Testi adlı kart oyununda sağlıklı oyuncular, riskli destelerin neden kötü olduğunu söyleyemeden önce, o destelere uzanırken hafifçe terlemeye başlıyordu; hastalarda böyle bir sinyal görülmedi. Kuram hâlâ etkili ama tartışmalı: eleştirmenlere göre bedensel sinyallerin seçimi mi yönlendirdiği, yoksa yalnızca ona eşlik mi ettiği henüz netlik kazanmadı.

Sources and further reading

Background reading: Somatic marker hypothesis
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