The color red is believed to increase receptiveness to external stimuli, which could affect a person's emotional and motor responses, researchers said.

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And the researchers believe it is possible that this interaction may change vital nervous system functions, including how quick it is to react to external stimuli.

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Using a technique called functional magnetic resonance imaging (fMRI), the researchers were able to record the brain's activity in response to internal and external stimuli such as eating and drinking.

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Using a remote controlled vehicle with a fitted video camera, the researchers set up tests to assess how seals reacted to external stimuli and potential threats, including wolf calls played from the vehicle.

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Using these bio-transistors, researchers gain access to data not previously available (like whether an individual cell has been exposed to certain external stimuli), in addition to allowing them to control basic functions like cellular reproduction.

ENGADGET

An external stimulus such as music can actually block some of the internal stimuli trying to reach the brain such as fatigue-related messages from muscles and organs.

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