Neuroticism

Neuroticism is one of the big five higher-order personality traits in the study of psychology characterized by anxiety, fear, moodiness, worry, envy, frustration, jealousy, and loneliness. Individuals who score high on neuroticism are more likely than average to experience such feelings as anxiety, anger, envy, guilt, and depressed mood. People who are neurotic respond worse to stressors, are more likely to interpret ordinary situations as threatening, and minor frustrations as hopelessly difficult. They are often self-conscious and shy, and they may have trouble controlling urges and delaying gratification. High neuroticism indexes a risk constellation that exists prior to the development and onset of any of the "common mental disorders", such as depression, phobia, panic disorder, other anxiety disorders, and substance use disorder—symptoms that traditionally have been called neuroses.

At the opposite end of the spectrum, individuals who score low in neuroticism are more emotionally stable and less reactive to stress. They tend to be calm, even-tempered, and less likely to feel tense or rattled. Although they are low in negative emotion, they are not necessarily high on positive emotion. Being high on positive emotion is an element of the independent trait of extraversion. Neurotic extraverts, for example, would experience high levels of both positive and negative emotional states, a kind of "emotional roller coaster". Individuals who score low on neuroticism (particularly those who are also high on extraversion) generally report more happiness and satisfaction with their lives.

Galen of Pergamom popularized the idea that mixes of four bodily fluids or humours resulted in four personality types or temperaments. The Melancholic personality type, which can be seen as the conceptual predecessor of Neuroticism, was characterized by being mentally unbalanced, fearful, anxious, or sad, and according to Hippocrates due to too much black bile.

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