A team of neuroscientists from the New School for Social Research in New York has announced that not only are the areas of the brain responsible for motor dominance on opposite sides of the brain for left-handed and right-handed persons, but certain emotion processing centers are reversed as well.
Using electroencephalography (EEG) to measure brain signals at rest and during the performance of certain activities intended to stimulate motivation, the scientists found that approach motivation, a personality characteristic governing what we are drawn toward, generates more activity in the left hemisphere than the right in right-handed people. Among those who are left-handed, however, the same activity is more measurable in the right hemisphere of the brain.
The team's findings were surprising because many cognitive functions have been found to remain isolated in one side of the brain or the other regardless of motor dominance. Language, the classic example, is almost always processed in the left hemisphere, whether a person is right- or left-handed. The idea to conduct this study arose from observations that motivation-related behavior tended to utilize motor actions based on side dominance. For example, right-handed people will tend to use their right hand for approach-motivated tasks and their left for avoidance-related tasks, but left-handers will use the opposite pattern.
The implications for the treatment of anxiety and depression are many. Since many protocols call for the stimulation of the left hemisphere, thought to be exclusively the approach motivation center, such treatments may be detrimental to left-handers, whose left hemisphere may instead lead to avoidance behavior. Left-handedness, then, may become another diagnostic and prescriptive criteria when deciding on anxiety treatments.
Source: PLoS ONE
Photo: Pixabay