Document discusses testosterone as a 'microcontroller' of competitive behavior

HARMING OTHERS, version 1.1: microcontrollers In any competitive situation, whether it is animals working out a strategy for maximizing the odds of obtaining food or humans working out a strategy for maximizing the odds of check mating an opponent’s king, someone will walk away as the winner and someone as the loser. Winning feels good and losing feels bad. Winning fuels confidence, losing lowers self-esteem. Depending on the opponent, including what they look like and whether they are familiar or unfamiliar, it is possible to gauge the likelihood of winning or losing in advance. Depending on the individual’s prior history of wins and losses, and details of his or her personality, some individuals will embrace the challenge of a high risk-high payoff strategy whereas others will adopt a low-risk low payoff strategy. Winning, losing, and taking risks are all mediated by differences in hormone levels, neurochemicals, and patterns of brain activation. Some of these differences are set by the individual’s biology, some change over the course of a year, some within a day, and some within the period of a brief glance that allows for an opponent to assess the competition. These physiological processes are the microcontrollers that regulate an individual’s motivation to fight or flee, as well as the sense of reward and loss that accompanies winning and losing. These microcontrollers adaptively regulate the capacity to harm, at least until they malfunction. Malfunctions, whatever their cause, can convert healthy, defensive, competitive, and justifiable harms into over the top excessive and unethical harms. One of the primary microcontrollers is the hormone testosterone. Though it is commonly assumed that testosterone is a male hormone, it is also present in females, though at lower concentrations. Testosterone plays an essential role in both sexual and aggressive behavior in all social animals. Testosterone surges when males defend their territories, and also, when they recruit sexually available females. Stronger surges occur when individuals are challenged by competitors who want their territory, food, mates, or position within a hierarchy. What this shows is that testosterone motivates animals within the arena of competition. Testosterone also surges again after an individual wins a fight, and drops following a loss. This is highly adaptive as it motivates winners to keep defending their resources, and motivates losers to give up and minimize future costs. Across a wide variety of species, humans included, winners are two times more likely to win the next fight whereas losers are five times less likely to win the next fight. These winner-loser effects are mediated by testosterone. In our own species, among male and female athletes, in sports including soccer, tennis and judo, winners show higher testosterone levels than losers. This effect even holds in non-physical competition, such as chess and stock trading. In a study of day traders on the London Stock Exchange, those making the highest profits had the highest levels of testosterone. Even those who are simply witnesses to a winning competition show increases in testosterone, including Hauser Chapter 1. Nature’s secrets 36 HOUSE_OVERSIGHT_012782