The Republican Brain by Chris Mooney is a good overview of the current information Psychologists have of the differences between the liberal and conservative brain. He presents the information accurately, and the overall analysis of the existing political climate is dead on. However, I certainly would have preferred that the title of the book be "The Conservative Brain", and that he forego the references to the political parties. After all, there really still are liberal Republicans and conservative Democrats running around the country even though they are relatively quiet, and I do want to make some comments about the lack of comprehensiveness of his research concerning personality factors.
While it is true that Psychologists have widely accepted the scales for measuring the "Big Five" factors that characterize the human personality, there is another personality test being used which we could call the "Big Three" to differentiate them. The name of the test is The California Psychological Inventory (CPI) which is published by the Consulting Psychologists Press. They both produce the same results except that the CPI reports generate a higher order concept called personality type. The "Big Five" generates scores on five factors or dimensions; Openness to Experience, Conscientiousness, Extraversion, Agreeableness, and Emotion Stability. The CPI generates scores on three factors or vectors; Externality vs. Internality, Norm-favoring vs. Norm-questioning, and Level of Satisfaction. I have a definite bias in favor of the CPI because it crosses the scores at their means and generates the higher level concept of "personality type". I have also relabeled the factors of the CPI to a more easily understandable Extravert vs. Introvert, Liberal vs. Conservative, and Adjustment to suit my needs. I have a graphic and a one page description of this on the home page of my website, [...].
I understand that he was focusing on the Republican Brain in the book and factors which cause them to deny scientific evidence which is why he only discussed and analyzed the research concerning Openness to Experience and Conscientiousness. I certainly wish he would have broadened his focus to include all `Big Five" dimensions or "Big Three" CPI vectors and personality types. There is a significant difference between the lifestyle and behaviors of Extraverted and Introverted conservatives. Similarly, there is a significant difference between Extraverted and Introverted liberals.
The liberal/conservative dimension does indicate differences in authoritarianism, closed mindedness, orderliness, sexual drive and creative sexual behavior, work/play ethic, recreational drug use, etc., but the extraverted/introverted dimension focuses on the huge differences in aggressiveness, dominance, risk-taking, lack of empathy, etc. By adding the extraverted/introverted dimension to his research and analysis, he would have given the reader a more complete understanding of human behavior. His discussion of the confrontational right wing "Tea Party'", Phyllis Schafly and son, and the vociferous, closed-minded, and strident science deniers could easily be explained by this personality dimension.
The remaining factor, Mental Stability in the "Big Five", and Adjustment as I use it in the CPI, is a separate dimension or vector that does not correlate with the other factors I discussed in the previous paragraphs. This means that scores on Openness to Experience, Conscientiousness, Extraversion, Agreeableness, or Extravert vs. Introvert, Liberal vs. Conservative, are measures of "normal" personality while a low score on Mental Stability or Adjustment would indicate some sort of pathological process that would have to be further tested or at least, explored. Other tidbits which would have helped him clarify some of the questions or statements he discussed in his book are:
1. Intelligence is not correlated with the other factors and is probably equally distributed among the four personality types.
2. Gender is not correlated with the other factors and is probably also equally distributed among the four personality types.
3. Physical attractiveness is not correlated with the other factors and is probably also distributed among the four personality types.
4. Race, hyper-sexuality, creativity, Ph.D.s, scientists, and recreational drug use tend to cluster on the liberal side of the mean.
5. Bigotry, hypo-sexuality, conformity, and religiosity tend to cluster on the conservative side of the mean.
And finally, his explanation of personality dimensions as a continuum was absolutely necessary to clarify the variance within the same personality type. People scoring closer (possibly some percentage of one standard deviation) to the means would be "blended"; a mix of liberal, conservative, extraverted, and introverted values, behaviors, and lifestyles. These people comprise the "independents", liberal Republicans, and conservative Democrats in our current political mix. I believe he is a blended personality type in attitude, behavior, and lifestyle.
I also liked his discussion of the growing evidence of genetic predisposition of personality. DNA makes the body and the brain, and with more integrated research as suggested by NIMH, personality type will eventually be explained as differences in brain anatomy, neurotransmitters, prenatal and postnatal hard wiring of the brain, or other physiological factors yet to be discovered.
Overall, I liked his writing style, and conscientiousness in completing his book. Because he is not a Psychologist, he obviously had to do a lot of research to discuss the topic of political psychology. I would recommend "The Republican Brain" as a "must read" for every extroverted and introverted liberal. I would also recommend it for conservatives, but I know they will not read it. It would produce too much cognitive dissonance for them.The Abomination Project