Is Your Brain Liberal, or Conservative?
A team of UCLA researchers, led by Marco Iacoboni, have been mapping the electrical activity of the neural structures in the brain as they respond to miscellaneous events, and had the subversive idea to show controversial political commercials to of all things—-Democrats and Republicans. One such commercial was footage of the smoldering Twin Towers site after 9/11. During the viewing of the scenes, the electrical activity of the various brain regions were measured, and some startling behaviors were revealed. It seems that the Democrats had higher average amygdala activation’s than the Republicans.
The amygdala in the right hemisphere functions differently than its leftward twin, and this difference coincides with the general differences in hemispheric processing. The left amygdala is entrenched in the language-based world of the left brain, and can be taught to fear something based solely on verbal clues, without having any direct contact. If someone tells you there is a shark in the ocean, your left amygdala will activate when you think about going swimming. However, if you see a shark swimming in the ocean, your right amygdala will activate as you watch it.
It seems the right amygdala is more responsive to existing environmental threats, and the left amygdala to verbal fear conditioning and anticipated threats. The right amygdala is more reactive than its left twin to other’s facial expressions and non-verbal vocalizations such as crying and laughing. More importantly is the right amygdala’s specialization for aversive emotions. The left amygdala, like the left brain, is the more positive amygdala. The right amygdala is also the anxious amygdala, and has been implicated in anxiety disorders with some help from the left amygdala.
The left brain is more electrically active than the right brain. The reasons behind this are still under investigation, but the ascending reticular arousal system, or ARAS, is the apparent culprit here. The reticular formation, which lives in the brainstem, has ascending fibers into the cortex and provides the energy to light it up. It is sort of like an electric cord for your toaster. Sever this connection, and the brain becomes comatose, eventually leading to death. The connectivity between the left brain and the ARAS exceeds that of the right brain.
The left brain draws more current from the ARAS, and speculation is that its monosemantic nature requires more activation to support the more structured connectivity. Conversely, the right brain seems to run on its own, as its neural network is all over the place, passing electrical current all around, not varying much even when in focused analysis. Additional activation from the ARAS will not improve right hemisphere functions. However, it will suffer the same fate as the left hemisphere when severed from its power source.