Liberals and Conservatives React in Wildly Different Ways to Repulsive Pictures

a recent strand of experimental psychology suggests, our political beliefs may have something to do with ... our propensity to feel physical disgust.... The brains of liberals and conservatives reacted in wildly different ways to repulsive pictures... different brain networks were stimulated... the subjects’ neural responses... could predict with more than 95 percent accuracy whether they were liberal or conservative... only the reaction to repulsive things correlated with ideology....
an ongoing discussion ... whether this is because disgust is simply a more powerful and more politically relevant emotion or because it is an emotion that is easier to evoke with still images in a lab setting...numerous studies have found that high levels of sensitivity to disgust tend to go hand in hand with a “conservative ethos.”... defined by characteristics such as traditionalism, religiosity, support for authority and hierarchy, sexual conservatism, and distrust of outsiders.... “disgust influences our political views as much as or even more than long-recognized factors such as education and income bracket.”...
disgust evolved ... to protect us from infection... the “behavioral immune system,” ... pathogen-tracking system ... beneath our conscious awareness   and pays close attention to those walking germ bags we call human beings... error-prone in flagging danger — it produces a lot of false positives... having germs on our mind can affect how we feel about people we perceive to be of a different race or ethnicity from ourselves... Familiarity does make a difference... if I grow up in New York City, then a person who comes from China is not going to trigger this response... theorize that foreigners, at least in the past, would have been more likely to expose local populations to pathogens against which they had no acquired defenses... resistance to immigration is greatest in states with the highest incidence of infectious disease and where worry about this, as reflected by internet activity, has also been high...
those with high disgust sensitivity tend to be leery of any stranger... Disgust and distrust are somehow linked... if you shrink your social circle, you’ll reduce your exposure to potential carriers of disease... disgust sensitivity may also help shape beliefs about right and wrong, good and evil... When we experience disgust, we tend to make harsher moral judgments... Religious strictures... may have the hidden function of protecting us from disease ... to respect certain culinary practices, sexual prohibitions, and injunctions about washing and hygiene...
what tastes foul ... sour or bitter ... can be a marker of contaminants ... people vary tremendously in the number of bitter receptors on their tongue... genetically determined... those self-identified as conservative were more sensitive to both compounds... Liberals tended not to be bothered or didn’t notice them at all...The degree to which subjects’ views tilted to the right was in direct proportion to the density of papillae on their tongue...
disgust... occupies a blind spot in our psyche... You hack into brains ... by making them feel disgust,” bypassing logic and reason to sway judgment.