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Mirror self-recognition is a hallmark of higher intelligence in humans.Most children recognize themselves in the mirror by two years of age.In contrast to human and some great apes,monkeys have consistently failed the standard mark test for mirror self-recognition in all previous studies.Here we show that rhesus monkeys could acquire mirror-induced self-directed behaviors resembling mirror self-recognition following training with visual-somatosensory association.Monkeys were trained on a monkey chair in front of a mirror to touch a light spot on their faces produced by a laser light that elicited an irritant sensation.After 2-5 weeks of training,monkeys had learned to touch a face area marked by a non-irritant light spot or odorless dye in front of a mirror,and by a virtual face mark on the mirroring video-image on a video-screen.Furthermore,in the home cage,5 out of 7 trained monkeys showed typical mirror-induced self-directed behaviors,such as touching the mark on the face or ear and then looking and/or smelling at their fingers,as well as spontaneously using the mirror to explore normally unseen body parts.Four control monkey of a similar age that went through mirror habituation but no training of visual-somatosensory association did not pass any mark tests nor exhibited mirror-induced self-directed behaviors.These results shed light on the origin of mirror self-recognition and suggest a new approach to studying its neural mechanism.