Have we been thinking about 'sex drive' all wrong?

Sex drive is a popular term, a catchall phrase for describing a person's ability to get turned on. But sex researchers say the term is poorly understood, frequently misused and often fails to capture the complexity of human desire.

Sex drive is not a clinical term, but a way people colloquially talk about arousal. Having a healthy sex drive is considered good for overall health, and the Internet is rife with articles claiming to offer solutions if a person feels their sex drive is low. But sex educators say our ability to get aroused is influenced by so much more than stress, sleep or even the quality of our relationships. Our sexual responses are the result of a balance between the things that excite us and the things that inhibit us, and are informed by all the messages we've gotten about sex, pleasure and safety since the moment we were born.

"If we have this idea in our brain that sex is a healthy, fun, pleasurable experience, then we're ... going to be able to access our sexuality in a positive, happy way," said Jenni Skyler, a certified sex therapist and the director of The Intimacy Institute. "But if we've gotten a lot of messages growing up, which is really common, that sex is dangerous or dirty, or you're going to get pregnant, or you're going to get an STD, or you're going to be called a slut, or you're going to be 'that person,' then you learn to shut down your sexuality. When you start to feel arousal, your brain goes, 'Oh! Oh, no, no. That's a dangerous feeling.'"

Sexual responses reflect a persistent tension between the present and the past, between the desire for pleasure and the fear of pain.

The problem with calling sex 'a drive'

Sex educator Emily Nagoski says the term "sex drive" is inherently inaccurate. Sex, she said, is not a drive at all. A drive is a biological mechanism that creates an uncomfortable internal experience and pushes us to go fix it – hunger is a drive (get more food), thermoregulation is a drive (get warm) and sleep is a drive (go to bed).

Sex is much more complicated.

The Dual Control Model of Sexual Response, developed by former Kinsey Institute director John Bancroft and Erick Janssen in the late 1990s, found sexual response was influenced by excitatory and inhibitory processes, two independent systems that vary from person to person.

Nagoski said you can think about it like having a gas pedal and a brake.

"There's not just an excitatory impulse, but also an inhibitory function that recognizes all the potential threats in the environment and sends a turn-off signal to prevent us from becoming aroused," she said. "It turns out when people struggle with any aspect of desire, arousal, pleasure, orgasm, sometimes it's because there's not enough stimulation to the accelerator, but much more often it's because there is too much stimulation to that brake."

Skyler said balance is the goal.

"If you have no brakes and all accelerators, we might be actually in overdrive and hypersexual modality," she said. "If we have all brakes, then we're going to be completely shut down to sex."

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The gas pedal and the brake pedal

Our environment is full of things that activate the gas pedal and the brake.

Accelerators can be anything from a sexy voice whispering or the smell of a partner right after a shower. It can be certain flavors that stimulate arousal.

"It's anything you think, believe, or imagine that your brain codes as a sex-related stimulus," Nagoski said. "Thinking sexy thoughts, watching a sexy film, reading a sexy book. Those things activate the accelerator."

Then there are the brakes.

Ian Kerner, a sex therapist in New York and author of "She Comes First," writes about how people have a finite list of things that activate the accelerator, but the list of things that make us hit the brakes could go on for days.

"It's stress, it's the kids, it's the global situation of the world, it's relationship conflict, it's your own sense of wellbeing inside your own body," Nagoski said. "It's almost anything. It's everything you see, hear, smell, touch, taste, think, believe or imagine that your brain codes as a potential threat. So this could be the sound of your dog scratching on the closed bedroom door. It can be grit in the sheets. It can be a trauma history."

Life experiences shape sexual responses

From the moment we are born, our brain is learning. Nagoski recounted a story of a woman who told her that she once watched her adult brother changing his baby daughter's diaper. At one point, the baby starts touching her genitals and the dad says, "Don't touch that."

In that moment of learning, Nagoski said, the baby is taught that sensations in her genitals mean threats, mean shame, mean danger.

"This little infant's not going to remember this moment, but it's going to accumulate with countless other moments with the same energy," she said. "By the time she gets to adolescence, there's going to be this dark place in her brain where genital pleasure should be and she is not going to know how it got there."

Early experiences in childhood and adolescence have a profound impact on our sexual responses as adults.

"When you talk about brakes, some of the brakes are very socially conditioned, or religiously conditioned, or even conditioned by our family of origin that sex is dirty or dangerous or on a list of things that should not be engaged in," Skyler said.

The good news, sex therapists say, is that these imprints are not permanent. Work can always be done to create a positive relationship to sex.

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Different contexts can make sensations feel different

Nagoski said she would love to be able to tell people to make a list of all the things that activate their accelerator and all the things that make them hit the brakes, and then encourage themdo everything they can to make a world where their accelerator gets activated and their brakes don't get hit.

But it's not that simple, she said, because human brains also respond to context.

Nagoski gives the example of tickling. If you're already in a turned-on, playful, erotic state of mind with someone you really love and trust, tickling, even if it's not your favorite thing, can feel good and lead to other things. But if you're in the middle of a fight with that same person and they tickle you, it's not going to feel fun or playful or good.

"It's going to make you kind of want to punch them in the face," she said. "It's the same sensation, but your brain changes how it responds to sensations based on the context. It is more likely to interpret a sensation as a threat, to move away from something that hits the brakes if you are stressed out, overwhelmed, feeling threatened and untrusting."

Low stress, high affection, high trust and explicitly erotic are usually the conditions that create a healthy context. Context explains why something that felt good yesterday may not feel good today.

"That's normal and healthy," Nagoski said. "That is not a problem. That's not a dysfunction of any kind. If a sensation that usually feels good, doesn't feel good now, there's nothing wrong with us. There was a change in the context. If we can figure out what that change was, then we can fix it."

Don't judge your sexual responses, be curious

Nagoski encourages everyone to be curious about their sexual responses and to never judge them.

"Curiosity is the replacement for judgment. It allows you to be aware of what's happening and to explore, which does not necessarily activate the accelerator, but it frees up the brakes so that the brakes are not getting in the way of what the accelerator wants to do," she said.

Skyler says if someone isn't feeling great about their sex drive, don't pathologize it.

The goal she said, is for people to be able to have sex that comes from a place of authentic interest and capacity for pleasure, no matter how often.

"It doesn't matter if you have a lot of brakes or a lot of accelerators," she said. "These are just parts of our humanity."

This article originally appeared on USA TODAY: Low sex drive, high sex drive and the complicated truth about desire