Our perceptions, of risk or anything else, are products of cognitive processes that operate outside our conscious control — running facts through the filters of our feelings and producing subjective judgments that disregard the evidence. The behavioral scientists Melissa Finucane and Paul Slovic call this the Affect Heuristic; it gives rise to what I call the risk perception gap, the dangers produced when we worry more than the evidence says we need to, or less than the evidence says we should. This is literally built in to the wiring and chemistry of the brain. Our apparent irrationality is as innate as the functioning of our DNA or our cells.
And some of the specific emotional factors that cause us to worry too much, or too little, seem to be built in too. Psychological research has identified a number of emotional “fear factors” that make some potential threats feel scarier than others, no matter what the evidence might say:
• Human-made risks scare us more than natural ones, so we are more likely to fear vaccines, radiation from nuclear plants, and industrial chemicals like fluoride than we are to fear “natural” hazards like unpasteurized milk, natural medicines, or carcinogenic radiation from the sun.
• Imposed risks scare us more than those we take voluntarily. Fluoridated drinking water, childhood vaccination, and pasteurization are all mandated by government. And radiation from nuclear accidents is imposed on us, compared with radiation from the sun, to which we expose ourselves voluntarily.
• Risks to kids scare us more, fueling fear of fluoride and childhood vaccines.
• We subconsciously weigh possible harms against potential benefits. When diseases like measles disappear, the benefits of the vaccines that vanquished them are no longer obvious. Fear of fluoride is greater now than it was when most Americans lost many teeth to decay.
More here – Undark