Resources: Understanding EDA
Why bother to measure both left and right? Shouldn’t the two sides be the same?
Traditionally people have measured only the “non-dominant” hand (left hand for a right-handed person) and most of the EDA results in the literature describe left-handed results. However, that convention began before neuroscientists showed that a variety of circuits on both sides of the brain are involved in eliciting electrodermal activity, including for example, the left amygdala and the right amygdala, each innervating the left and right sides of the electrodermal response, respectively. Furthermore, brain imaging has shown that the left and right hemispheres can be differentially activated in some conditions such as depression, and anxiety. Some researchers have also looked at hemispheric differences in brain imaging related to positive/negative and to approach/withdrawal. When the brain imaging shows differential activation, we can expect that the skin conductance might also be differentially activated. Studies can now begin to examine left-right differences on both wrists or both palms using a pair of Q sensors.