About 90% of people use their right hand for almost all activities, while the remaining 10% is split between the left-handed and the ambidextrous, people who use either hand with equal comfort. But these "inconsistent-handers" pay a price for their ability to use either hand - a truly bizarre study has discovered that they're much easier to emotionally manipulate than their right-handed counterparts.

Montclair State researcher Ruth Propper studied how right-handers and ambidextrous people respond to emotional commands. She played various types of classical music and then asked the test subjects to think happy, sad, or nervous thoughts. The results were striking - the ambidextrous subjects reported an immediate onset of negative feelings when they entered the lab, and they consistently found themselves falling into the requested moods throughout the experiment. The right-handers, on the other hand, were far more rigid and unmoving in their emotional makeup.

Propper believes this goes back to how our brains are organized. Ambidextrous people tend to have an unusually large corpus callosum, which is the structure that links the right and left hemispheres of the brain. The increased communication between hemispheres would explain not only the handedness flexibility but also the greater emotional suggestibility.


There are potentially even deeper structural reasons. There's some thought that the left hemisphere - which controls the actions of the right hand - is charged with maintaining constancy in how we view the world, while the right hemisphere - which controls the left hand - deals with noticing changes and telling the other hemisphere that it's time for an update. In the case of ambidextrous people, Propper speculates that the increased communication between these two regions and the greater access to the brain's anomaly detector could make a person far more willing to change his or her mind.

Via New Scientist. Top image by M.C. Escher.