Wednesday, April 15, 2009

morality and the dopamine reward system


neuropolitics.org | Hillary Clinton's proposal that "it takes a village to raise a child", and the conservative response, "it takes a family", highlights the genetic bandwidth variations in their respective social attitudes. All of our cognitive data on conservatives indicate a general bias towards altruistic behaviors over a smaller range of genes than liberals. These two political cohorts are playing two divergent sides in the same evolutionary game, with the conservatives favoring smaller, genetically similar social groups, while the liberals favor larger, genetically diverse social groups.

This evolutionary game is survival of the gene, with the conservatives banking on force of numbers to provide their genes an advantage in future generations. That is, if gene A from one parent is combined with gene A from another parent, then the offspring carry two copies of gene A. The liberals are banking on the value of diversity, with gene A from one parent combining with gene B from another parent, and hoping that the heterozygous condition of both genes A and B will have an advantage over the homozygous condition in future generations.

This is evident in the greater propensity of liberals to interbreed across racial barriers than conservatives. We have previously proposed that the coefficient of inbreeding, F, is higher in conservative populations than in more liberal populations, although this difference is generally quite small, except in isolated religious groups.

Conservatives and liberals are, for the most part, unaware of this evolutionary game. So how are they playing it so successfully? We have long proposed that conservatives are more under the influence of the dopamine system in their cognitive styles, while the liberals are more likely to reflect the cognitive style of the noradrenergic (and serotonergic) systems.

The dopamine system is asymmetrically distributed in the left hemisphere, while the noradrenergic and serotonergic systems are asymmetrically distributed in the right, which is the reason we refer to "left-brained" conservatism and "right-brained" liberalism. Indeed, there is evidence that if these two hemispheres are separated by commissurotomy, they create two simultaneous and opposite political orientations in the same person! In one sense, we might all be conservative and liberal, with one mode being favored while the other is suppressed by the phenomenon of hemisphericity, or the way the brain resolves conflicts between competing neural regions in the brain.

And once again, the dopamine system also seems to be behind the conservative and liberal variations in the tolerance for genetic distance.