"Temperament" was the buzzword of Monday night's presidential debate, the first between Democratic candidate Hillary Clinton and Republican candidate Donald Trump.
The most tweeted-about line of the night, according to The Hollywood Reporter, was Trump saying, "I think my strongest asset, maybe by far, is my temperament. I have a winning temperament. I know how to win. She does not."
Later, Clinton said that some of Trump's foreign-policy statementsrevealed a person without the right temperament to be commander in chief. [The 5 Strangest Presidential Elections in US History]
Merriam-Webster's dictionary defines "temperament" as "the usual attitude, mood or behavior of a person or animal," but psychologists use the term a little more specifically. In 1981, psychologists Mary Rothbart and Douglas Derryberry defined the term as "individual differences in reactivity and self-regulation assumed to have a constitutional basis." By "constitutional," the researchers meant that these differences are based in the "relatively enduring" biology of the person, and are influenced by genetics, they wrote in the Journal of Personality and Social Psychology in 2000.
This definition encompasses mood and emotion but also includes processes such as attention and even heart rate. For example, a more reactive person might experience a heart-thumping response to a loud noise, whereas a less reactive person might not have that visceral response.
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Despite this rather permanent view of temperament, Rothbart and her colleagues soon discovered that their original global approach didn't always pan out. In the first studies of infant temperament, for example, the researchers tried to find out if some babies might be more intense than others in all of their reactions and behaviors. It didn't work out that way, the researchers wrote in their 2000 article. A baby who tended to laugh and smile easily and intensely did not necessarily get intensely frustrated as well, the scientists found.
Nevertheless, the researchers were able to discover aspects of temperament that are more stable, such as level of activity and the ability to maintain attention. Following children from infancy to age 7, they found that fearfulness in infancy predicts fearfulness in childhood; positive anticipation, or excitement about upcoming activities, also remained stable over time. [10 Things You Didn't Know About You]
In Monday night's debate, Clinton and Trump seemed to use the word "temperament" almost interchangeably with the concept of personality. In psychology, however, personality is defined as individual differences in patterns of thinking, feeling and behaving, according to the American Psychological Association. Unlike temperament, psychological traits don't necessarily have to be innate. Personality emerges from the interaction of temperament and life experiences. The boundaries between the concept of inborn traits and traits that are developed as a result of the environment are fuzzy, though.
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