A self-assessment Internet survey was conducted by Brack and Zhang on Neuro-politics.com. The survey collected 418 questionnaires after the inclusion of Gender to the survey, of which 42 cases were subsequently cleansed for probable duplicate or incomplete responses. This left 376 usable questionnaires, of which 179 indicated support for George W. Bush, 170 for John Kerry, and 27 for unspecified other candidates. This survey period was January 28 through March 4, 2005. The survey questions were adapted from similar left-right brain surveys, with slight variations. Since Gender was added later during the survey, we do not have the same number of usable observations as in Part 1 of this study.

Females exhibited similar variations in left versus right orientations as males, but with less polarity. Female Conservatives exhibited elevated left brain scores relative to both Female Moderates and Female Liberals, but neither was statistically significant (p < .58) and (p < .09), respectively. In contrast, the Male Conservatives exhibit a statistically significant variation with Male Liberals (p < .01). There was also a statistically significant difference in left brain scores when compared to the Male Moderates (p < .01).

Female Liberals exhibited no statistically significant variance in left brain scores when compared to Female Moderates (p < .55). Male Liberals also showed no statistically significant variance in left brain scores when compared to Male Moderates (p < .46).

With regard to right brain scores, Female Liberals show a statistically significant variation with both Female Conservatives and Female Moderates, (p < .03) and (p < .01), respectively. Female Moderates exhibited no statistically significant right brain variation from Female Conservatives (p < .33).

Male Liberals exhibited a statistically significant right score variation with both Male Conservatives and Male Moderates, (p < .01) and (p < .01). Male Conservatives showed no statistically significant variation in right scores when compared with Male Moderates (p < .28).

The largest contributor to cohort variance was found in Reality-Model preferences, which was true for both females and males. The Female and Male Conservatives had significant preferences towards organized and unambiguous Reality-Models, such as "good" and "evil" or "right" and "wrong". Liberals of both genders exhibited a low preference for binary Reality-Models, and Moderates fall in between for both females and males.

Female Liberals had noted elevations in visual-artistic skills, and Male Liberals exhibited elevations in musical-artistic skills, although our survey did not properly identify their musical hemispheric preference.

Female Conservatives exhibited a noted elevation in emotional recognition skills, and enhanced literal language processing skills. Female Liberals had an elevation in affective language processes.

Male Conservatives had elevations in literal language processing, and the Female Conservative had a noted elevation in arithmetic skills. Male Moderates reported the highest arithmetic rating, but the largest deficit in literal language processing. Female Moderates exhibited a strong ability for literal language processing, but had the smallest and therefore most unreliable sample statistics (N=22).

Male Liberals reported the highest deficit in our time planning and vector-of-time ratings, and the greatest aversion to behavioral routines. Female Moderates had a noted deficit in emotional recognition skills.

The Female Conservatives exhibited a dramatic elevation in the Very Religious scale, doubling the next closest cohort, the Male Conservatives. The Male Liberals had a dramatic elevation on the Not Religious scale, followed in second place by Female Liberals. The Male and Female Moderates exhibited the two highest Little Religious scores, followed closely by the Male Conservatives. Note that we did not get one response for a Female Conservative that described herself as Not Religious, although we had about 20% of the Male Conservatives and 27% of the Females Moderates classify themselves as Not Religious

Female Conservatives were the least hemispherically "polarized" of the females. The Male Moderates were the least hemispherically "polarized" of the males. However, low female response rates indicate unreliable sample statistics for their cohorts.

Male Conservatives and Male Liberals were polarized in their responses by almost 50% over their female counterparts. This may be reflective of the research pointing to enhanced lateralization of the male brain, at least for the attributes under study.

1 A. Left-Brain Scores By Political Affiliation By Gender

Note that we are using the following abbreviations: Female Liberal (FL), Female Moderate (FM), Female Conservative (FC), Male Liberal (ML), Male Moderate (MM), and Male Conservative (MC).

Graphically:

There was a notable increase in mean left responses as one moved from left to right in the political spectrum across gender. Female mean left hemisphere responses are greater than male for every political cohort. Due to the low female sample sizes, no comparison is slightly statistically significant except for the Female Liberals versus Female Conservatives (p < .09). However, their sample mean differences are comparable with males. The Male Conservatives had statistically significant variations in the sample means versus both Male Liberals and Male Moderates (both p < .01). See Table 17.

1 B. Right-Brain Scores By Political Affiliation

Taking the Left-Hemisphere score and subtracting the Right-hemisphere score for each respondent, we compute a Difference variable that is analogous to a Hemispheric Bias for the mental attributes we surveyed. This is not to be confused with brain dominance, which was not explicitly measured in this survey. Our Hemispheric Bias is negative for right brain oriented respondents, and positive for left brain oriented respondents.

Graphically:

Interestingly, the Males Moderates had an exact aggregate number of Left and Right responses in our survey, even though they had 74 respondents. This does not imply hemispheric balance in the Male Moderates, rather, it is mainly an artifact of the survey design. However, the placement of the Males Moderates in between the Liberals and Conservatives should happen in most surveys, regardless of the numbers of left and right oriented questions.

Males exhibited a slight elevation in difference scores when compared to their female counterparts, even though they have lower average right and left scores. If you divide difference scores by total mean responses for each Political-Gender cohort, you get Figure 11.

The Male Liberals and Male Conservatives exhibit an almost 50% greater polarization in responses relative to their female counterparts. The Female Moderates, on the other hand, exhibit a greater polarization than their male counterparts. However, the low Female Moderate sample size (N = 22) does not allow us to infer much about this relationship.

We have focused primarily on statistical analysis of summary data, but this doesn't tell us much about how our political-gender cohorts vary from each other. The survey consisted of 29 left or right questions, with two control questions placed at the end to detect completeness of the survey. We will now focus on the questions that were mostly responsible for separation of the sample means, ones that contributed to a 0.1 or greater difference between Conservatives and Liberals and examine the impact of Gender on them. These questions will appear in the same order as Part 1 for ease of reference.

A "Yes" to this was scored as a left-hemisphere response. This is predominately a left-hemisphere binary categorization. Binary views of "Right" and "Wrong" or "Good" and "Evil" are left hemisphere belief-biased events. Belief-biased events have been localized in the left temporal lobe by V Goal and RJ Dolan (1). Interestingly enough, Goal and Dolan also found belief-neutral reasoning originated from a bilateral parietal lobe system, and activation of the right lateral prefrontal cortex was evident when subjects inhibited a belief-biased response. Note the dramatic differences in the Conservatives and Liberals across gender.

A "Yes" to this was scored as a left-hemisphere response. Ornstein, Herron, Johnstone, and Swencionis (2) found that EEG activity in the right hemisphere predominates when reading fiction, EEG in the left hemisphere predominates when reading science textbooks. Responses are consistent across gender except for the Male Conservatives, which exhibit a strong preference for non-fiction.

Question 1: I always wear a watch.

A "Yes" to this was scored as a left-hemisphere response. Watch or clock reading are predominately left hemisphere events. The vector of time is theorized by Rotenberg (3) to be a left hemisphere function. Data is consistent across gender, except for the Female Conservatives, which may be a statistical fluctuation due to the small sample size (N=36). Large gender difference in this question.

Question 9: I am pretty good at arithmetic.

A "Yes" to this was scored as a left-hemisphere response. Stanescu-Cosson et al (4) provided evidence that exact calculation has been associated with the left inferior prefrontal cortex and the bilateral angular regions. Approximation involves a bilateral prefrontal system. Chochon F et al (14) detected asymmetries in cortical activation for multiplication (primarily left hemisphere) and subtraction (bilateral). This is possibly explained by the connection between rote verbal learning of multiplication tables (mainly in the left hemisphere). Note that the Male Moderate reports the greatest arithmetic proficiency, and coincidentally, is the least lateralized of all cohorts in our study. The Female Conservative is also the least lateralized of the females, and coincidentally reports the highest arithmetic proficiency.

Question 28: When I'm confused, I usually go with my gut instinct.

A "Yes" to this question was scored as a right-hemisphere response. In retrospect, this is questionable. Goel et al(5) found that when a logical argument results in a belief-logic conflict, the nature of the reasoning process is changed by the recruitment of the right prefrontal cortex. Our results may infer that normal left-hemisphere belief-based logical conflicts, presumably self-assessed as "confusion", result in reliance on the intervention of right hemisphere processing, also self-assessed as "instinct". Therefore, the question may not be detecting hemispheric dominance as much as what happens when the left-hemisphere cannot resolve an internal logical inconsistency. The high response of the Female Conservative is not inconsistent with the hypothesis that they readily recruit right hemisphere processing in certain adaptive responses. Consistent with Question 9, where we see both the Male Moderate and Female Conservative exhibiting elevated recruitment of right hemisphere functionality in problem resolution.

Question 25: I lose track of time easily.

A "Yes" to this question was scored as a right-hemisphere response. This is a similar question asked in the opposite to "I always wear a watch". As we discussed previously, the vector of time is a left-hemisphere event. Variances are remarkably similar across gender.

Question 4: I find it hard to follow directions exactly.

A "Yes" to this question was scored as a right-hemisphere response. The brain's left-hemisphere bias for processing language syntax is well documented. This question implicates written and/or verbal instructions being more difficult for the Female Liberal, Male Liberal, and Male Moderate cohorts. Right-hemisphere language processing is more effective with short phrases, and has a much more limited short-term memory than the left-hemisphere (7). Females exhibit a general advantage consistent with other gender studies in verbal learning (15).

Question 16: I am musically inclined.

A "Yes" to this question was scored as a right-hemisphere response. This is questionable, in that hemispheric dominance for melody recognition varies based on level of exposure and has been shown by Bever and Chiarello (6) to be different for the musically trained (left-hemisphere oriented analysis) and untrained (right-hemisphere oriented). Formulation of this question does not sufficiently delineate a direction of hemispheric bias. Interesting to note is the Male Liberal exhibits greater polarization from the Male Conservative, when compared to their female counterparts.

A "Yes" to this was scored as a right-hemisphere response. Recent neurochemical evidence by R Kurup and P Kurup (8) indicates asymmetrical neurotransmitter patterns in creative versus non-creative people. This pattern in non-creative individuals correlated with that obtained in left hemispheric chemical dominance. The pattern in creative individuals correlated with right hemispheric dominance. This analysis presumes that creative people find that schedules are more "boring" than non-creative people. There is a strong elevation in the Male Liberal relative to the Male Conservative, although a similar, but less dramatic pattern occurs between their female counterparts.

Question 8: If I don't know which way to turn, I let my emotions guide me

A "Yes" to this was scored as a right hemisphere response. The right hemisphere generally predominates in emotional processing. Right hemispheric bias in activation in autonomic responses suggests that the physiological response system rather than the perceptual/cognitive system is the locus of the right hemisphere superiority for emotion (9). Unusual pattern for the Female Moderates, possibly due to their small sample size. Note the difference between Male Liberals and Male Conservatives is much stronger than their female counterparts.

Question 18: When I talk, I gesture a lot with my hands

A "Yes" to this was scored as a right-hemisphere response. Even though motor planning of hand movement predominates in the left-hemisphere, Lausberg, Davis, and Rothenhausler (10) found that gestures with emotional connotation are generated predominately in the right-hemisphere. Note the Female Liberal variance from the Female Conservative is greater than their male counterparts. Perhaps an indicator of a stronger female preference for right hemisphere language processing in the Female Liberal, even relative to the Male Liberal.

Question 11: I'm frequently late getting places

A "Yes" to this question was scored as a right-hemisphere response. This is a similar question to 25, "I lose track of time easily". The Male Liberals exhibit a more dramatic elevation to the Male Conservatives than their female counterparts. This is generally true of all the vector-of-time related questions.

Question 24: I've considered becoming a poet, a politician, an architect, or a dancer

A "Yes" to this was scored as a right-hemisphere response. Poetry is more metaphoric and non-literal, both well-documented right hemisphere biased functions. Architecture is visuospatial, another right-hemisphere oriented function. Dancing is indicative of motor coordination and grace of performance of nonverbal behavior as a whole are under the control of the right hemisphere (12). Politician is questionable, and may be related to a stength of political belief issue. This may account for the wider variation on the female side of this scale.

A "Yes" to this was scored as a right-hemisphere response. Recent reports of changes in art performance among patients with frontotemporal dementia suggest that visual art is predominantly in the right hemisphere. By contrast, the left hemisphere may be inhibiting it (11). Females, on average, report a higher tendency for visual-artistic activities than males, and a wider liberal-conservative gap.

A "Yes" to this question was scored as a left-hemisphere response. The results run counter to the liberal-right hemisphere tendency, which may indicate a scoring inconsistency. Possible emotional link to journal or diary-keeping. Response rates are low, especially for males.

Question 19: I believe there are two sides to every story.

A "Yes" to this was scored as a right-hemisphere response. This is similar to our "I believe there is a right and wrong way to do everything" question, but asked in the opposite. We do not get the wide separation that was exhibited in the question 3, presumably because this question is more of an interpretive aspect in human conflict situations. A noted drop in both the Female Conservative and Male Conservative responses.

The above questions contributed to a 0.1 or more difference in overall average differences between Conservatives and Liberals.

We will now consider some notable questions that did not meet this criteria, but warrant some discussion.

A "Yes" to this was scored as a right-hemisphere response. There is a stronger and consistent tendency for males to draw maps than females, except in the case of the Female Liberal. This is consistent with the Female Liberal's elevated responses for "I like to draw", and enhanced tendency for visual-artistic activities.

Question 10: If I had to assemble something, I'd read the directions first

A "Yes" to this was scored as a left-hemisphere response. This question contributed little to the variance between Conservatives and Liberals, but is interesting to note the gender differences, presumably due to an enhanced tendency for non-verbal problem solving with males.

A "Yes" to this was scored as a right-hemisphere response. This question showed strong elevations on the female side, with the conservatives of both genders with a slight elevation over their liberal counterparts. This is possibly related to the female advantage in emotional recognition, particularly facial emotions, by Thayer and Johnsen (16). Possible emotional recognition advantage for Female Conservatives, as Female Liberals spend more effort with visual spatial right hemisphere components.

A "Yes" to this was scored as a right-hemisphere response. Female superiority for emotional recognition is exhibited here. All females are higher than their male counterparts

A "Yes" to this was scored as a left-hemisphere response, but in retrospect, this is questionable. Analysis of alexithymia in split-brain patients indicates a bilateral system of emotional articulation (17). A noted elevation across females, and consistent with studies indicating a more bilateral language orientation in females.

A "Yes" to this was scored as a left-hemisphere response. Noted elevation in verbally based memory triggers on the female side.

The Male Liberals indicate a strong bias towards being Not Religious. The Female Liberal pattern is similar, but not as pronounced as the male pattern. The moderates indicate an elevation in the Little Religious category for both genders. The Female Conservatives indicate a strong Very Religious preference, and the Male Conservatives are biased towards Little Religious. Note that we did not find one Female Conservative that indicated a preference towards Not Religious, possibly due to a low sample size.

In our survey, the Female Conservative was more 14% likely to score a -2 or less (right hemisphere bias) than the Male Conservative. In contrast, the Female Liberal was 7% less likely to score a -2 or less right score than the Male Liberal. This indicates a greater tendency for the Female Conservative to exhibit right brain biases compared to her male counterpart. The Female Liberal was not as inclined to exhibit right brain biases as her male counterpart, and this again may be due to a more bilateral orientation in females as has been proposed by several studies.

Conversely, the Male Conservative was 18% more likely to score a +2 or more (left hemisphere bias) than the Female Conservative. The Female Liberal was 5% more likely to score a +2 or more than the Male Liberal. This indicates that a Female Conservative is less likely to exhibit left hemisphere tendencies than her male counterpart, and the Female Liberal was more likely to exhibit left brain tendencies than the Male Liberal. Again, the Male Conservatives and Liberals are more polarized than their female counterparts.

We cannot say too much with respect to the characteristics of females due to low sample sizes, despite specific targeting during our survey period, which was not necessary for males. But this is indicative of the tendency of females to generally be less politically active than their male counterparts. More interesting still is the dramatic difference in response rates of Female Liberals compared to Female Moderates and Conservatives. Female Liberals were more likely to participate in our survey, and were a larger component of the total liberal responses (46%) than either the Female Conservatives (27%) or Female Moderates (23%).

This Female Liberal elevation in participation may be consistent with her orientation towards right-hemisphere visuospatial processing, and a more extended view of the subjects in her political world. In other words, the Female Liberal may be more motivated by issues such as global warming that extend well beyond the local circle of family, friends, and others that are experienced in daily life.

In contrast, the Female Conservative's orientation towards right-hemisphere emotional recognition is well positioned for this local view. This model would propose a different orientation of the right hemisphere of the Female Conservatives as compared with the Female Liberals---one favoring emotional recognition, and one favoring visuospatial processing. However, we cannot discount other influences in the relative response rates, such as statistical anomalies or problems with our sampling methodologies.

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