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In a 1998 experiment, people watched a rubber hand being stroked with a brush while their own hand, hidden from view, was stroked at the same moment. Many soon felt the touch on the rubber hand, as if it had become part of their body.

Botvinick & Cohen, Nature (1998)

MindScience

The story behind the card

Matthew Botvinick and Jonathan Cohen reported the finding in a one-page paper in Nature titled 'Rubber hands "feel" touch that eyes see'. The illusion works because the brain decides what belongs to the body partly by matching what the eyes see with what the skin feels. Later studies showed that people's skin starts to sweat, a sign of alarm, when the rubber hand is suddenly threatened, and in 2008 Valeria Petkova and Henrik Ehrsson used cameras and head-mounted displays to make people feel a whole mannequin's body as their own. Researchers now use such illusions to study phantom limb pain, body image and how people might come to feel a prosthetic limb as part of themselves.

Türkçe oku
1998'deki bir deneyde katılımcılar, önlerindeki kauçuk bir ele fırçayla dokunulmasını izlerken, göremedikleri kendi ellerine de aynı anda aynı biçimde dokunuldu. Birçoğu kısa süre sonra dokunuşu kauçuk elde hissetmeye başladı; sanki o el bedenlerinin bir parçası olmuştu.

Matthew Botvinick ve Jonathan Cohen bu bulguyu Nature dergisinde, “Kauçuk eller gözün gördüğü dokunuşu ‘hisseder’” başlıklı tek sayfalık bir yazıyla duyurdu. Yanılsama, beynin neyin bedene ait olduğuna kısmen gözün gördüğüyle derinin hissettiğini karşılaştırarak karar vermesinden doğar. Sonraki çalışmalar, kauçuk el birden tehdit edildiğinde insanların derisinin terlediğini, yani vücudun alarm verdiğini gösterdi. Valeria Petkova ve Henrik Ehrsson da 2008'de kameralar ve başa takılan ekranlarla insanlara bir mankenin bütün bedenini kendi bedenleri gibi hissettirdi. Araştırmacılar bugün bu tür yanılsamaları hayalet uzuv ağrısını, beden algısını ve insanların bir protezi nasıl kendi uzvu gibi hissedebileceğini incelemek için kullanıyor.

Sources and further reading

Background reading: Rubber hand illusion
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