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The cocktail-party effect is our ability to follow one voice in a noisy room while tuning out the rest. In the 1950s Colin Cherry tested it by playing a different message into each ear: listeners could follow one and remembered almost nothing of the other. In 1959 Neville Moray showed their own name could still break through.

Colin Cherry; Neville Moray

MindScience

The story behind the card

Colin Cherry was a British engineer and cognitive scientist at Imperial College London, and he published his first results in 1953. His listeners had to 'shadow' one ear, repeating its message aloud as they heard it, which left little attention for the other ear: they noticed if the ignored voice changed from a man's to a woman's, but not if it switched to another language. Moray found that about a third of listeners noticed their own name in the ignored ear, a sign that some meaning is processed even without attention. Engineers still speak of the 'cocktail-party problem': picking out one voice from background noise remains hard for hearing aids and speech-recognition software.

Türkçe oku
Kokteyl parti etkisi, kalabalık bir ortamda öbür sesleri bastırıp tek bir konuşmayı izleyebilmemizdir. Colin Cherry 1950'lerde bunu, kulaklıkla her kulağa ayrı bir konuşma dinleterek sınadı: katılımcılar birini izleyebiliyor, öbüründen neredeyse hiçbir şey hatırlamıyordu. 1959'da Neville Moray, kişinin kendi adının yine de dikkatini çekebildiğini gösterdi.

Colin Cherry, Londra'daki Imperial College'da çalışan İngiliz bir mühendis ve bilişsel bilimciydi; ilk sonuçlarını 1953'te yayımladı. Deneyde katılımcılar bir kulaktan gelen konuşmayı duydukları anda yüksek sesle tekrarlıyordu; bu yüzden öbür kulağa pek dikkat kalmıyordu. Dinlenmeyen taraftaki sesin erkekten kadına dönüştüğünü fark ediyor, ama başka bir dile geçtiğini fark etmiyorlardı. Moray, dinleyicilerin yaklaşık üçte birinin dinlemedikleri kulakta geçen kendi adlarını fark ettiğini buldu; demek ki dikkat vermediğimiz seslerin anlamı da bir ölçüde işleniyor. Mühendisler bugün hâlâ “kokteyl parti sorunu”ndan söz eder: bir sesi arka plandaki gürültüden ayırmak, işitme cihazları ve konuşma tanıma yazılımları için zor bir iş olmayı sürdürüyor.

Sources and further reading

Background reading: Cocktail party effect
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