The Left Amygdala in the Hat Comes Back
The Neuropsychology of the Apocalypse
by Charles Brack
I am a conservative, a conservative am I, and I do not like that socialism-pie
The conservatives took heavy casualties in their latest altercation with the liberals, which was one of the epic battles in American political history: the Battle of ObamaCare. There were no dead bodies, but rather, a relative reduction in the future presence of Caucasian genes in the gene pool. Based on our very rough estimates of the impact of disposable income on fertility, in 20 years, this reduction in the genetic presence of upper-tax bracket Caucasians translates to 27,000 future lives.
This is a substantial loss for the genetics of the upper income Caucasians, which are more reproductively proficient than the middle and lower classes, and whose incomes have been targeted by the Obama reforms via increased tax rates. The relationship between reproductive yield and disposable income is a close one.
While modern political battles are pristine versions of full-scale warfare, their long-term impact on population gene frequencies is the same. Political wars frequently employ the weaponry of income redistribution, and like violent warfare, target the long-term reproductive capacity of the participants and their relative genetic presence in the gene pool in future generations.
Having lost the Battle of ObamaCare, what do the American conservatives do now? As the Caucasian population continues its relative decline, the conservatives are caught between a gigantic European-style liberal pincer movement from the north, and a rapidly growing pincer of Hispanics, Blacks, and Asians from the south.
Stuck in the middle, the carnage of future conservative (aka Caucasian) population gene frequencies is driving them into a full-fledged separatist movement. Separatist conflicts are fundamentally genetic conflicts, and the dynamic of rapid political polarization, currently on display in America, typically precedes them.
But even if some conservatives manage break free from the United States of America, where are they going? Texas, the home of three of the last nine U.S. presidents, and where John F. Kennedy was killed, originally seceeded from Mexico in 1836, under circumstances similar to today. The Mexican government, in their ongoing battle with the indiginous Indian tribes, liberalized immigration policies, bringing an influx of Caucasians from the United States.
The political conflict associated with these new immigrants was exacerbated when the Mexican central government attempted to increase political and economic control. The Caucasians in Texas successfully executed their war of independence, and briefly became an independent nation, before returning to their genetic origins, and accepting statehood into the United States.
Texas would eventually become the poster child for the space and energy hungry model of Caucasian reproduction. Texas has the highest per capita energy consumption in the continental United States, and among all the United States, only the frigid Alaska uses more energy on a per capita basis. This would not necessarily be a political problem for a geographically insulated state, except that Texas just happens to be at the nexus between Caucasian and Hispanic genetics.
A Texas secession would reduce both political conflict and genetic variation in the United States
The Caucasian model of reproduction leaves large holes easily penetrated by populations that can reproduce with less energy. Further, the strong capitalistic orientation of Texas takes quick advantage of energy utilization differentials between populations, and promotes immigration and racial mixing (see Capitalism, Communism, and Population Genetics). Aggressive capitalism goes hand-in-hand with rapid shifts in population gene pools, and the Caucasians in Texas could not resist the cheap labor supply from their southern border.
In twenty years, the Hispanic population is expected to exceed the Caucasian population. Even if Texas seceeded, it would soon be faced with an internal political struggle that would threaten its own southern border. The territorial integrity of any nation is better sustained if there is greater genetic divergence across borders than within the nation itself, and Texas is in major violation of this principle. In short, Texas has no where to go.
Regardless of the consequences, the tone of secession is likely to permeate Texas politics indefinitely. Central governments typically have separatist pressures in territories that vary in both geographic and genetic distance from the capital city. Under these circumstances, the greater the tendency for central control, the greater the separatist pressures.
Further, there is a tendency for resources to flow from remote territories and towards political capitals, creating additional secessionary pressures. Capital cities, by virtue of their function as political power centers, induce the flow of money from the far reaches of their territories. This natural tendency is a politically destabilizing force in any nation, particularly if it correlates with the asymmetric distribution of genetics.
Freedom, liberty, and the mesolimbic dopamine system
There is one ubiquitous conservative preference that substantially exceeds the preference for the belief in God--freedom. Freedom and its identical twin, liberty, are the universal answers to any liberal political argument. It justifies exercises of military power, trumps any argument for health care reform, vanquishes any hyperbole towards social equality, and erodes any regulations that might be thrust upon a corrupted financial sector. The greater the preoccupation with freedom, the more conservative one is likely to be, and the more likely one is to own a gun.
In 2005, we introduced the hypothesis that this overwhelming conservative preference is mainly a by-product of the functioning of the dopaminergic system (see Freedom's just another word...). The dopamine system forms the backbone of many of the cognitive attributes and behaviors typically associated with conservatism: lowered cognitive ambiguity; elevated levels of suspiciousness of strangers and an enhanced sense of threat from outgroups; enhanced competitiveness; greater tendency for the seeking of physical rewards; stronger religious orientation; and, a greater desire for energy and space.
The dopamine system, asymmetrically expressed in the left hemisphere, is also the backbone of the behavioral activation system. Specifically, the mesolimbic pathways of the dopamine system are instrumental in reward encoding, initiation of motor activity, and reward-seeking behaviors. Further, the mesolimbic dopamine pathways are part of the brain's action extrapersonal visuomotor system, which is oriented towards the upper visual field, and heavily implicated in religious activity (Previc, 2006).
We propose that the dopaminergic system, most notably the mesolimbic pathways, are the principle driver for the conservative mantra of freedom. Freedom, from the perspective of the dopamine system, facilitates the functioning of reward-seeking and motor activity, which is why it has such a unanimous appeal for the dopamine-toned conservatives.
Further, the amygdala, an almond-sized group of nuclei located in the medial temporal lobes of each hemisphere, is plugged right into the mesolimbic dopamine system, and heavily engaged in fear conditioning, among other politically salient functions.
The rise of militant conservatism
One of the more interesting trends in the American political portfolio is the rapid rise of the militant right wing, as noted by the Southern Poverty Law Center. This recent increase is almost completely Caucasian, and highlights the fundamental human organization for intergroup conflict: a small band of genetically and geographically similar males. Militias are typically small--less than 100 members. In these paramilitary groups, as in the animal kingdom in general, displays of force are much more common than the actual exercise thereof, and pseudoconflict is their primary outcome.
Historically, upsurges in militia activity correlate with liberal presidencies: Franklin Roosevelt, John F. Kennedy, Bill Clinton, and Barack Obama. Right-wing militant organizations tend to fall into two types: groups that are religiously flavored and have a strong focus on reproduction (e.g., anti- homosexuality and abortion); and, militias organized almost exclusively for competition with outgroups (including the federal and state governments). Both types are monoethnic and maintain low levels of genetic distance within their ranks, at least when compared to the general population.
In the U.S., the number of militias grew from 42 in 2008 to 127 in 2009
The demographic tendencies of these organizations are typically suburban, exurban, and rural. New recruits are typically males between 20 to 50 years of age. Most are gun enthusiasts prior to enlistment, and almost all of these organizations purport some form of secret conspiracy to take over the United States, such as: the federal govenment and its socialistic policies; the international cabal of Jewish bankers; the Council on Foreign Relations; the Trilateral Commission; the United Nations; etc.
But there is good reason to believe that the recent uptick in conservative fear and anger is related to the aforementioned relationship between conservatism and the dopamine system. While fear and anger can be traced to many diverse neurophysiological processes, the conservatives seem to be more impacted by the dopaminergic system's contribution of these survivally salient emotions. In particular, the current upswell in militant conservatism can probably be traced mainly to the functioning of the mesolimbic dopamine system and the hyperactivation of the left amygdala.
The revenge of the conservative media
Journalism tends to be a liberal occupation. While the conservatives complain endlessly about this, there is a very good neuropsychological reason: conservatives tend to be more cognitively oriented to the processing of inanimate objects, while the liberals tend towards biological cognition (liberals also predominate in the biological and social sciences). The follows the dichotomy of the left and right hemispheres.
Given this liberal journalistic bias, ironically, conservatives have a stronger propensity to consume media such as political talk radio and television. Liberals spend more time on the internet than do conservatives, however, we have not yet captured their political versus non-political internet consumption.
We have previously argued that conservatives have a greater need for this type of exposure, and further, have a stronger propensity to become psychologically attached to a particular media personality (e.g. Rush Limbaugh, Bill O'Reilly, and Glenn Beck). This argument follows from our proposal that conservatism is more dopaminergically toned than liberalism.
The liberals are more natural when it comes to self-regulating their social behavior, as they are more likely to engage the innate neural networks associated with empathy, which are asymmetrically distributed in the right hemisphere. Conservatives need more help, and their behavioral self-regulation is more likely to be socially modulated, and communicated via language.
The social modulation of conservative beliefs makes a good argument that, over time, these beliefs are more variable than their liberal counterparts. For example, conservative opinions on slavery are more socially modulated than liberal opinions. 150 years ago, conservatives held much more favorable opinions of slavery than did the liberals. This same pattern is seen with civil rights, social security, and medicare, all of which experienced high levels of initial conservative opposition, only to be accepted over time, as these attitudes become socially modulated.
Conservatives also seem to be susceptible to the viewpoints of particular individuals, that is, conservatives are more likely to seek out a single individual that provides them with a socially organizable viewpoint. This is especially true of religious conservatives, as seen in the strong influence wielded by their religious leaders.
There are two aspects of conservative cognition that support this argument: first, conservatives have a greater propensity to organize into dominance hierarchies, and, once organized into those hierarchies, are more likely to execute the demands of the highest levels (see How Conservatives and Liberals Organize into Social Groups); second, conservatives have a stronger drive towards unambiguous cognition, and this need is filled daily by Glenn Beck, Rush Limbaugh, Bill O'Reilly, etc.
An important point to make here is that these are daily shows, and supports the stronger propensity that conservatives have towards coordinating their attitudes with each other in the confusion of the daily news cycle. Ratings for daily conservative talk media substantially exceed their liberal counterparts, even when controlling for the relative sizes of the respective conservative and liberal populations.
Both conservatives and liberals seem to be elevating the activation levels of their dopamine reward systems by this daily habit of consuming partisan political media. This was noted in an experiment by Westen et al. (2006), in which conservatives and liberals were caught activating their dopamine reward systems as they experienced positive information about their favorite political candidates. Conservatism and liberalism may correlate with enhanced states of the activation of the dopamine reward system in the left and right hemispheres, respectively (see Political-Religious Disposition and the Dopamine Reward System).
This raises an interesting question with respect to variations in political disposition: does political disposition vary over the span of a week? We have proposed annual and diurnal cycles in political disposition (see Cycles in Conservatism and Liberalism), due to the daily cycles in the activation levels of the politically-hot monoamine neurotransmitter systems (dopamine, serotonin, and norepinephrine).
However, these variations tend to be slight, and only involve the processing of new and politically salient stimuli. A weekly cycle would presumably be correlated with elevations in political polarization during the work week, and may be influenced by working and its impact on increasing the activity in our monoamine transmitter levels. We presumably revert back to normal "non-working" activation levels on the weekend, and a corresponding decrease in polarization.
While this is interesting speculation, weekday political talk shows certainly seem to be more polarized than those on weekends. However, so far, there are no formal studies to corroborate this proposal. Further, it is also very probable that the weekday news shows contribute to this heightened polarization during the work week.
The conservative elevation in the consumption of politically-polarized media also seems to be related to the particular sensitivity that conservatism has towards language communication. In one of our earlier studies, liberals reported greater difficulty following verbal conversations (see Anxiety, Depression, and Goal-seeking in Conservatives, Liberals, and Moderates). In that same study, we also noted that conservatives had a greater preference for semantic versus shape translation for a word pair.
This enhanced orientation towards language is also seen anecdotally with the religious, with their elevated importance of written canon (e.g., "the Good Book", "the word of God", "Ten Commandments"). Further, there is a strongly enhanced tendency for the religious conservatives to literally interpret religious scripture when compared to religious liberals.
This greater conservative and religious orientation towards organizing their social behavior via language communication would seem to follow from the conservative left brain, liberal right brain hypothesis. Language processing is asymmetrically distributed in the left hemisphere, and the elevated role the left hemisphere plays in conservative attitudes might imply that it is more likely to be modulated by language communication.
The politics of instinct: fear and the amygdala
There has been some talk of the social dangers of neuropolitics and the associated understanding of how the human brain organizes its political and religious orientations. Some critics posit that this might lead to mass control over the political and religious attitudes of large segments of the population.
It's a little late for that. All gregarious species have evolved effective communication methodologies that manipulate the emotional states and behaviors of conspecifics. These methodologies are focused primarily on the transmission of six classes of information: fear and fight-flight; food sources; territory and possessions; dominance and submission; predation-aggression; and, mating. Of these six classes, fear and fight-flight typically induces the greatest physiological and behavioral response.
The evolutionary precedence of the communication of fear-fight-flight has been retained, and spectacularly so, in human political behavior. The communication of fear in humans has taken an interesting turn, which has curiously been enmeshed with the linguistic evolution of the brain, and in particular, the left hemisphere.
Any discussion of the brain's rendering of fear must start with an evolutionarily ancient neural structure known as the amygdaloid complex. One of the major functions of the amygdala is a sort of early-warning system for potential threats, and this function extends to facilitate learning, giving us improved memory retention when those memories are formed under heightened emotional states.
In humans, the amygdaloid complex, or amygdala, contains bundles of neurons deep within the temporal lobes of the left and right hemispheres. These bundles contain projections to and from diverse regions in the central nervous system, including the prefrontal cortex, as the amygdala is a major integrative region in the brain.
The function of the amygdala is central to the survival of the organism. This is evident in the anatomy, as the central nucleus of the amygdala just happens to be the most neuropeptide-rich region of the brain. The significance of this is that neuropeptides tend to have prolonged impacts on central nervous system functions, especially when compared to ordinary neurotransmitters. The amygdala can not only trigger emotional states quickly, it can modulate these emotional states for long periods of time, especially in the absence of inhibiting inputs from the prefrontal cortex.
Don't shoot until you see the whites of their eyes
Indeed, it is this curious interplay with higher cerebral function that make the amygdala such a politically hot region of the brain. One of the more interesting aspects of amygdalar processing involves responsiveness to the whites of eyes. The amygdala is sensitive to scleral field size, or the white area of the eye. Whalen et al. (2004) not only found that the amygdala is activated by the detection of increased eye white area, but this also occurs when one is not even consciously aware of the eye stimuli.
In short, the amygdala is living in a world of its own, mostly detached from participating in conscious mental processes, and frequently at odds with other, more recently evolved regions in the brain. This conflict with other neural regions is manifest in the low-spatial frequency of amygdalar processing. The amygdala can respond rapidly to very limited information, and is important in the startle response.
At this point, we must note one of the seminal findings in the short history of neuropolitics, which was the report by Hibbing et al. (2008) on the physiological responses of conservatives and liberals to threatening stimuli (e.g., a spider on the face of a frightened person). The physiological responses measured were skin conductance and startle eye blink.
Hibbing found that those with conservative political attitudes had a heightened startle reflex to threatening stimuli, and further, implicated the amygdala in this elevated response. Hibbing noted:
Alternatively, political attitudes and varying physiological responses to threat may both derive from neural activity patterns, perhaps those surrounding the amygdala. There is a connection between localized activation of the amygdala and aversive startle response. Amygdala activity is also crucial in shaping responses to socially threatening images and may be connected to political predispositions. Indeed, given that political and social attitudes are heritable and that amygdala activity also has been traced to genetics, genetic variation relevant to amygdala activity could affect both physiological responses to threat and political attitudes bearing on threats to the social order.
The racist amygdala and the Conservative left brain, Liberal right brain hypothesis
However, this was not the first experiment that the amygdala has reared its ugly head when it comes to political attitudes. Earlier evidence that the amygdala was weighing heavily on racial attitudes, which correlate closely with political attitudes, came from Hart et al. (2000), with their Differential Response in the Human Amygdala to Racial Outgroup vs Ingroup Face Stimuli. Hart found elevated amygdalar activity in response to viewings of black and white faces to opposite race faces.
These elevated activations persisted during repeated viewings of the opposite race faces, an interesting result, particularly given the strong persistence of racist attitudes. Indeed, the reactivity of the amygdala to opposite race faces, namely Obama's, is the main driver for the current Tea Party movement.
Adding more fuel to the link between racist attitudes and the amygdala, Phelps (2000) found that while the amygdala were activated in viewing opposite race faces, "the region in the amygdala most strongly correlated with negative evaluation [of black faces] was the left-superior amygdala". Further, it seems that the resolution of race occurs more quickly than does the resolution of individual facial features.
However, the racist tendencies of the amygdala appear to have a nemesis, and one that is further evidence in support of the Conservative left brain, Liberal right brain hypothesis. Conservatives report higher levels of racial prejudice than liberals, and interestingly, the right hemisphere, particularly the right dorsolateral prefrontal and anterior cingulate cortices, have been identified by both Richeson (2003 ) and Cunningham (2004) as inhibiting the elevated activations of the amygdala in responding to race.
Conservative left amygdala, Liberal right amygdala
We shall shortly discuss the conflict between the amygdala and the prefrontal cortex, one of the more politically relevant conflicts in the brain. One of the major reasons the Conservative left brain, liberal right brain hypothesis explains much of the variation in political orientation is due to asymmetries in amygdalar processing. While most studies on the left and right amygdalae typically treat them as one functional unit, more recent research is implicating variation, and politically relevant variation at that.
In particular, the left amygdala is more specialized for the processing of fear than is the right. Hardee et al. (2008) tested this asymmetry in amygdala processing, and found that the right amygdala was reactive to happy faces, gaze shifted eyes, and fearful faces. Further, the right amygdala showed no significant preference in reacting to these different conditions. The detection of fear and happiness generated similar responses in the right amygdala.
Specialization of the left amygdala for fear. So much political trouble from a very small region in the brain. These results from the Hardee et al. experiment indicate the specialization of the left amygdala for fearful faces. In contrast, the right amygdala also responded to happy faces and gaze shifts. Does this specialization for fear contribute to the conservative's greater suspiciousness of strangers and outgroups?
We must note that the right amygdala reacted more strongly to fearful faces. However, the left amygdala only responded to the detection of fearful faces. Further evidence of this left amygdala specialization comes from Wright et al. (2001), which found that the left amygdala exhibits greater differential response to negatively versus positively valenced stimuli.
Wright et al. also noted an interesting asymmetry in the habituation of the respective amygdalae to repeated stimuli: "the right amygdala exhibits significantly greater habituation to emotionally valenced stimuli than the left. In contrast, the left amygdala responds significantly more than the right to negatively vs positively-valenced stimuli".
While the right amygdala reacts more rapidly to a wider spectrum of environmental cues, it attenuates more quickly, while the left amygdala maintains longer focus on threatening stimuli. This may be the result of the extended memory support function of the left amygdala, as it needs to buffer aversive stimuli longer so as to link it to a variety of other stimuli.
Amygdalar disruption of the prefrontal cortex
No mental disorder has been as connected to hyperreligiosity as paranoid schizophrenia. This, by virtue of the close relationship of political conservatism and hyperreligiosity, hints at common neural substrates. Indeed, paranoid schizophrenia, a mental disorder often related to the hyperfunction of the mesolimbic dopamine system, has also been associated with the reduction in activity in the right amygdala (Pinkham et al., 2008).
Conservatives are certainly more suspicious of outgroups than liberals, and we suspect that the left amygdala is a major contributor to this attitude. Further, the conservatives seem to be more reactive to verbally communicated fear learning. It is interesting that the amygdala in the left hemisphere is highly responsive to fear learning via verbal communication, while the right amygdala appears to neutralize this tendency (Gazzaniga, 2004).
It is also interesting that conservatives have a higher propensity to consume politically-charged media relative to liberals, and the high levels of threat associated with the content of these political talk shows seem to be increasing the release of dopamine, particularly in the mesolimbic pathway.
But the story of the human amygdala is also the story of how neural evolution integrated the rapidly growing prefrontal cortex with phylogenetically ancient and behaviorally critical structures such as the amygdala. This interaction is mutual, that is, neurons in the amygdala project into all areas of the prefrontal cortex and vice versa.
The amygdala is a major integrative region in the brain
The brain has evolved to execute multiple responses to the same sensory input over time. This is evident in they way sensory input follows two distinct pathways to get to the amygdala: a direct relay from the thalamus (thalamo-amygdala pathway); and, a longer route, from the thalamus to the cortex and then on to the amygdala (thalamo-cortico-amygdala pathway). The thalamo-amygdala pathway is quicker, but the increase in speed sacrifices the level of understanding of the stimulus. As such, it facilitates quick reactions to fast approaching objects, spiders, snakes, etc.
The thalamo-cortico-amygdala pathway is slower, but provides a better assessment of the associated threat presented by the stimulus. The interaction of the prefrontal cortex and amygdala is one of the more politically relevant neural networks in the brain. This is highlighted by the way the elevated response of the amygdalae to opposite-race faces is dampened by the right dorsolateral prefrontal, as previously mentioned.
In elevated states of danger, the amygdalae will interfere with the operation of the prefrontal cortex by facilitating the release of adrenocorticotropic hormone (ACTH). This impairment of prefrontal activity was also noted by Richeson (2003) among whites with elevated levels of racial prejudice. It seems that the more racist one is, the more cognitively disrupted one is in the presence of other races.
The mounting evidence indicates that in mammals, each portion of the prefrontal cortex has a distinctive projection to the amygdala. Further, the ventral areas of the lateral and medial prefrontal cortices, which receive olfactory projections, are the only prefrontal cortical areas with projections to the olfactory-related superficial amygdaloid nuclei. The specificity of prefrontal cortico-amygdaloid projections is indicative of their involvement in discrete functions (Mcdonald et al., 1996).
The connectivity between the ventral medial prefrontal cortex (VMPFC) to the amygdala and olfactory regions has vaulted it into one of the more politically prominent neural networks in the brain, and something that shows up repeatedly in politically relevant fMRI (Grafman, 2006 and Westin, 2006).
The neurological picture of the VMPFC is highly enmeshed in reward, particularly in the evaluation of the value and selection of alternate rewarded outcomes (Arana et al., 2003), which the VMPFC seems to be very specialized for, as opposed to resolving differences between two alternate punishments, or the difference between a reward and a punishment (Blair et al., 2006).
The VMPFC and the amygdala, which itself has been implicated in maintaining the reward values for food types (see Arana), are part of the brain's neural network for generating emotive states. These emotive states compete with brain areas that promote cognitive states that may come into conflict with optimizing self-interest, such as the right dorsolateral prefrontal cortex. This was noted by Goel (2003), when the VMPFC, along with the left temporal cortex, would prefer biased responses over pure deductive reasoning.
Thus, the amygdala is one of the main areas of the brain that promote self-interest, and can interfere heavily with prefrontal activity originated cognition that has no positive self-interest. This is particularly true of the left amygdala, and its impact on political-religious disposition often leads to incongruent beliefs and behaviors. For example, there are many recipients of government payments and health care benefits that protest socialism and government health care, and the left amygdala, along with the left VMPFC, are two of the more prominent contributors to the strong hypocritical drive in humans.
The left amygdala in the hat comes back
According to Drew Westen, there are over 250 studies that have found that conservative attitudes are promoted by thoughts of death. This, we propose, is the direct result of the activation of the left amygdala that is induced by the contemplation of death.
The apocalyptic reaction of many conservatives to the Obama Presidency has traces of the left amygdala written all over it. The amygdalar reactivity to opposite-race faces is the trigger for the fear that many conservatives have for Obama, and subsequently induces the fight or flight responses associated with amygdalar activation.
The left amygdala is particularly sensitive to threatening facial features
Further, the amygdala can induce negative emotional states for long periods of time, particularly if prefrontal cortical activity is not sufficient to attenuate amygdalar activation. The left brain is especially susceptible to verbally communicated threat, given its strong language orientation and the left amygdala's elevated reactivity to threats communicated via language.
The threats communicated by conservatives are typically quite simple, avoid activation of the higher cognitive processing areas of the prefrontal cortex in favor of ventral PFC and temporal activation, and based on simple one or two-word phrases, such as death panels, socialism, communism, fascism, Hitler, Stalin, etc. These are also words that have been introduced as threatening words early in life.
Glenn Beck has become extraordinarily effective at communicating threat to conservatives, via classroom blackboards, word analysis, and threatening symbols. He is no doubt charging the mesolimbic dopamine system among his many devoted fans, which works to increase the level of their bonding to him (analogous to romantic bonding brain mechanisms), and ironically, increasing the experience of reward in their brains.
Thus, the coming apocalypse, that never ever seems to happen, as much as we might want it to. But it really doesn't matter, because it's the journey, rather than the destination, that charges the mesolimbic dopamine system.
Charles Brack, May 2010
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