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Why do women tend to be less confident than men? Can the confidence gap between genders be explained by genetic differences between males and females?
While there are no genetic differences between men and women—the confidence-related gene variants are evenly distributed between genders—the sexes do have physiological differences in their brains, think in different ways, and have different amounts of relevant hormones. Some of these differences may explain the confidence gap between men and women.
Here is what neuroscience has to say about the confidence gap between men and women.
Brain Differences and Confidence
Women’s and men’s brains differ in the following ways:
Size and Distribution of Brain Matter
- Women’s brains are smaller and lighter relative to body size than men’s. This doesn’t affect IQ. (Though some tests have found that women do better than men in language arts, and men are stronger in spatial skills and math.)
- Women have a larger cingulate gyrus (the part of the brain that spots mistakes, considers options, and worries).
- Most of women’s brain matter is in the frontal cortex (reasoning hub) and some of it is in the limbic cortex (emotional hub). Men’s brain matter is distributed throughout the brain and less than half is in the frontal cortex. This suggests the sexes process information differently.
- Women have more white brain matter (used for making connections) and men have more gray matter (used for solving problems).
- Women’s white matter often functions better than men’s, particularly the white matter in the corpus callosum (the part of the brain that connects the left and right hemispheres). This suggests women can more easily use both sides of their brains. The left side is responsible for logic and math and the right for emotion and creativity; using both helps us multitask and is cognitively advanced.
- Women’s brains are more active than men’s, especially in the prefrontal and limbic cortex. According to psychiatrist Daniel Amen, the activity in these places is probably responsible for women’s skills with empathy, collaboration, and multitasking, among other things. But, this activity also makes women more vulnerable to ruminating and confidence-killing anxiety.
- For example, one study found that women’s brains are firing 30% more neurons than men’s.
- Women use the amygdala (primitive fear centers) associated with thoughts, emotions, and memory more often than the one associated with action in response to negative emotions. Men do the opposite.
An active brain was useful in earlier times—worrying and paying attention to our surroundings helped us survive. Today, however, we don’t have to worry about predators lurking in the bushes. It’s still useful to make good decisions and avoid bad impulses, but ruminating and worrying don’t make us happy or confident.
- Women’s brains produce around half the serotonin men’s do.
- Women who have the two short-strands version of the serotonin transporter are more likely to be anxious than men with this version (though neither sex is more likely than the other to get this version).
- Similarly, women who have the “worrier” COMT variant are more likely to be anxious than men who have it.
When Do These Differences Develop?
These differences in thinking and even capability show up at different stages of development:
- Israeli researchers found differences between girls’ and boys’ brains at 26 weeks after conception.
- The National Institutes of Health found that by age 11, girls are behind boys in spatial ability, and boys are behind girls when it comes to processing emotions and language. Anatomically, their brain capabilities match up again at around age 18.
Scientists don’t know if these brain differences are due to how we’re raised, how we act (for example, we may have more white matter because our women ancestors used it more), or whether they’re programmed in.
Scientists do know that brains are plastic—they can change. All of us, regardless of age, can physically change our brains, which means that if you choose to change your thinking and mental habits, you can rewire yourself to be more confident, regardless of your genes or sex.
There are a few strategies you can use to rewire your brain. Both shift activity from the amygdala to the prefrontal cortex.
Strategy #1: Cognitive behavioral therapy is a technique for managing worst-case scenario thinking.
- For example, for people who were afraid of spiders, cognitive behavioral therapy involved talking about how tarantulas were scared of people and how people’s fears of tarantulas were unfounded. (For instance, tarantulas aren’t constantly plotting how to jump on people.)
Cognitive-behavioral therapy is the most effective strategy.
- For example, one study scanned the brains of people who were afraid of spiders as they looked at photos of spiders. There was action in the amygdala and the other parts of the brain involved with fear. After two hours of behavioral therapy, the participants had a normal amount of amygdala action and more activity in the prefrontal cortex. They were even able to touch a live tarantula. The effects lasted at least six months—when people were retested, they could still touch spiders.
Strategy #2: Meditation. Meditation can quiet the amygdala.
- For example, one experiment on stressed business people found that their amygdala shrank after meditation.
Memory and Plasticity
Memory is also a factor when it comes to plasticity and our ability to choose confidence—our past experiences inform what we think will happen in the present. This influence can be unconscious—one study discovered that the hippocampus, which is responsible for consolidating memories, can affect our choices.
- For example, a study asked participants to play video games in which they had to choose between two images, one of which would reward them. Later, in a different game, participants were asked to pick two images again, but this time, there was no reward. The participants often chose an image that had been beside the rewarded choice in the first game. They had no conscious memory of choosing that image for a reason, but their brain scans showed the hippocampus lighting up as they decided on the image.
You can’t control your unconscious, but you can build up new, positive memories for it to draw on instead. This will help you break free of habitual negative thoughts. Cognitive neuroscientist Laura-Ann Petitto describes this process as akin to building an overpass. If something happened in your childhood that shook your confidence, this created a memory highway in your brain. Your brain will reflexively go down the highway when you encounter situations similar to whatever created the highway. You might not ever be able to tear up the highway, but you can build overpasses and take those routes instead.
Hormones and Confidence
Now, we’ll discuss two hormones that may be implicated in the confidence gap between genders: testosterone and estrogen. Both men and women have testosterone, but post-puberty, men have around 10 times more than women.
Testosterone is responsible for muscle size, speed, strength, and feelings of power. It’s also related to risk-taking, ignoring warnings, and the “winner effect” (winning creates testosterone, which then encourages additional risk-taking in the hopes of winning again).
- For example, Cambridge University scientists tested the testosterone levels of male stock traders for a week. When they started the day with higher testosterone levels, they made riskier trades. When these trades worked out, their testosterone levels rose significantly.
Testosterone limits certain abilities, like cooperating and seeing other people’s points of view.
- For example, one study asked pairs of women to look at two images and agree on which was clearer. The pairs of women who received a testosterone supplement had more difficulty agreeing and were more often wrong.
Women can increase their testosterone levels by adopting male postures, like taking up space while sitting.
Estrogen encourages observation, social skills, and connection. Like testosterone, it has limitations too—it contributes to risk avoidance, which can kill confidence.
However, risk aversion isn’t always bad and estrogen’s effects can enhance performance and success. Taking big risks doesn’t always work out well.
- For example, one study found that over five years, women hedge fund managers’ investments did three times better than men’s.
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- An examination of the art and science of confidence
- Why women have more trouble accessing confidence than men
- How to build confidence in yourself and others