DISOWNING an arm or a leg despite the fact that it is still attached to the body is a common symptom of stroke, anorexia and schizophrenia. And, curiously, the temperature of these rejected limbs is always low.
Now Lorimer Moseley at the University of Oxford and colleagues have who have been tricked into disowning a limb. The work implies a more complex relationship between mind and body than had been thought.
The so-called 鈥渞ubber hand illusion鈥� is induced by stroking a person鈥檚 hand while it is out of their sight and at the same time stroking a visible rubber hand. The trick makes the subject perceive the rubber hand to be their own. Moseley鈥檚 team discovered in a similar test that this feeling is accompanied by reduced blood flow and a drop in skin temperature in the 鈥渞ejected鈥� limb.
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快猫短视频s believe that body temperature is automatically regulated by a part of the brain called the thalamus. In this 鈥渂ottom-up鈥� system, the body tells the thalamus what to do. Now Moseley鈥檚 team suggests that a 鈥渢op-down鈥� system also exists, in which higher cognitive processes control body tissues.
The experiment suggests that the conscious sense of who we are is intimately linked to our physical bodies. 鈥淭his is pretty ingenious. They have shown a direct link between body ownership and the physiological system,鈥� says Henrik Ehrsson from the Karolinska Institute in Stockholm, Sweden.
鈥淭he experiment suggests that the conscious sense of who we are is intimately linked to our physical bodies鈥�
The Human Brain 鈥� With one hundred billion nerve cells, the complexity is mind-boggling. Learn more in our cutting edge special report.
