SNAP!. Gary Small

He turned and asked one of the gigglers instead. As Emma watched them walk to the dance floor, her inner voice screamed, What is your problem? He was cute and you are an idiot. Then she calmed herself by repeating her mantra of late: Forget about it; he was probably married or a jerk anyway.

      Emma reached for her third dinner roll, but there was no more butter. She grumbled to herself, I should have stayed home.

      Emma is one of the millions of people who suffer from excessive shyness and insecurity. She knew this about herself and accepted her fate. Sure, she would have liked to be more extroverted and open to new things, but that just wasn’t the personality she was dealt.

      The term personality is derived from the Latin word persona, which refers to the theatrical masks worn by actors to display various roles or to hide their true identities. Today we think of personality as incorporating an individual’s characteristic patterns of thoughts, feelings, and behaviors. How we feel and think drives our behavior and causes us to act in certain ways.

      Your personality traits tend to remain consistent over the years, and they have a major impact on your love life, career success, health outcomes, and even life expectancy. And although some of us may act in similar ways, no two people share the exact same character style.

      Most people have a pretty good sense of who they are—they know themselves to be a certain way and behave accordingly. If you consider yourself to be creative, you probably do original things. If you think of yourself as generous, you are likely to be a giving person. If you believe you are overly sensitive, you probably get your feelings hurt a lot.

      Sometimes it’s easier to identify the personality traits of other people than it is to accurately describe yourself. Think of a few people you know, perhaps siblings, friends, or work associates. You may be able to sum up their personalities in one word: Jim is bossy; Carol is intellectual; Sharon is temperamental; Peter is conscientious. Of course, one word is insufficient to define a whole person, but we tend to use these labels as shortcuts to determine how we will respond and act toward others.

      Traits versus States

      When we refer to someone’s personality traits, we usually mean the consistent emotions and behavior patterns they display over time (e.g., generosity, moodiness, shyness). By contrast, emotional states stem from more transient thoughts and feelings that drive our behaviors, often in response to external stimuli. For example, your brother may be a basically cheerful person, but if faced with a major loss or disappointment, he might become depressed for a while. His depressed mood would be a temporary state he is experiencing due to his current situation.

      My patient Frank, a single father, was a self-described worrywart. Even when his life was going well, Frank would obsess over what might go wrong next. When his son was in elementary school, Frank worried about getting the car pool to school on time. When his son got a driver’s license, he fretted about the boy getting into an accident. Frank’s anxiety levels were certainly elevated compared with a person who was less neurotic, but they didn’t change that much from day to day. Worrying was one of Frank’s lifelong consistent traits.

      Eventually Frank’s son did have a car accident, although no one was seriously hurt. When Frank received the call, his anxiety escalated to the point that he couldn’t catch his breath and he thought he was having a heart attack. After a normal cardiogram in the emergency room, the doctor diagnosed the episode as a panic attack with hyperventilation. Frank took a mild tranquilizer, breathed into a paper bag, and was able to calm down. His panic attack was a temporary emotional state—a reaction to an upsetting incident—and was not a regular trait or characteristic of his personality.

      How Personality Is Formed

      Doctors and other experts have long theorized that our personalities are formed in early childhood and remain consistent throughout life. Research has suggested that by first grade, children have already developed personality traits that can predict their adult behavior.

      When I began to study psychiatry, I delved deeper into various theories of personality formation. Sigmund Freud speculated that each child progresses through different stages of psychosexual development, which shape that person’s long-term disposition. Erik Erickson described eight stages of developmental crises that mold personality. He speculated that an individual’s insecurity stemmed from an impasse during one of those eight stages, such as young adulthood, when struggles with intimacy versus isolation are common. Behaviorists like B. F. Skinner and John Watson held that personality stems from interactions between the individual and the environment. Carl Rogers, Abraham Maslow, and other humanist theorists emphasized free will and experience as the driving forces that form personality.

      John Bowlby theorized that an infant’s early attachment or basic need for closeness with their first caregiver (usually the mother) was the basis for that child’s long-term adaptive strategies to relationships, which can influence personality traits. Bowlby posited that a baby who received caring and consistent parenting early in life would form a secure attachment and grow to be an independent, self-reliant, and curious person. However, infants who don’t form a secure attachment may become needy, insecure, and distrustful of others and may have difficulty making friends.

      During my psychiatry training, I found these and other theories to be interesting, but I conjectured that a person’s early life experiences could not be the whole story. Even though I was taught to understand personality at a psychological level, I presumed that genetics must come in to play. Studies have shown that identical twins who share 100 percent of the same DNA are significantly more likely to share personality traits than fraternal twins who share only 50 percent of their DNA. This early work and later studies made clear that our genes do affect our personalities. However, the relationship is complex, and no specific personality gene has yet been discovered.

      Research indicates that the heritability of our personalities—or what proportion of our character is inherited from our parents—varies from about 40 to 60 percent depending on the particular personality trait being considered. That means that for the average person, about 50 percent of what determines their personalities is not genetic—each of us may have much more control over our personalities than we realize.

      What Is Personality?

      If you think about the various people in your life, you can probably come up with several different adjectives to describe their personalities—both positive and negative—including the ones below:

      Common Personality Traits

Positive	Negative
Bold	Timid
Calm	Short-tempered
Flexible	Rigid
Funny	Humorless
Generous	Self-centered
Modest	Arrogant
Outgoing	Shy
Trustworthy	Dishonest

      Of course, a generally positive trait can convert to a negative one if it becomes too extreme. A flexible person may be willing to compromise and get along with others, but being too flexible could make one indecisive and afraid to take a stand. Outgoing people tend to attract many friends, but some outgoing individuals go too far and become intrusive.

      For years, psychologists have grappled