Introduction
Welcome back. In our last lesson, we distinguished between spontaneous and responsive desire, establishing that desire doesn't always precede pleasure. We concluded that for many people, especially in long-term relationships, desire emerges in response to a pleasurable context. You'll recall that we touched on the idea that both desire types are governed by the same underlying brain mechanism: a system of accelerators and brakes.
Today, we will explore that mechanism in detail. Our learning outcome is to explain the dual control model of sexual response, focusing on the interplay of sexual excitation and inhibition systems. This model is one of the most significant advances in sex research, offering a powerful framework for understanding why we get turned on—or not—in any given situation.
For your goal of building a personal relationship framework, this knowledge is foundational. It moves beyond a simple list of "turn-ons" and "turn-offs" to help you understand the process of arousal itself. This insight is invaluable for communicating needs, troubleshooting sexual challenges, and intentionally creating contexts for intimacy and pleasure with partners.
The Core of the Model: The Brain's Accelerator and Brakes
At its heart, the Dual Control Model, developed by researchers John Bancroft and Erick Janssen and popularized by Emily Nagoski, posits that your sexual response is controlled by two independent systems in your brain.
- The Sexual Excitation System (SES): This is your sexual accelerator. Its job is to notice all the sexually relevant information in your environment—everything you see, hear, touch, smell, taste, or imagine that your brain has learned is sexual—and to send a "go" signal.
- The Sexual Inhibition System (SIS): This is your sexual brake. Its job is to notice all the reasons not to be aroused right now—any potential threats, dangers, or distractions—and to send a "stop" signal.
To get a clear and concise introduction to this concept, please watch the following short video.
This video, 'How Does Arousal Work?' by sex educator Erika Lynae, offers a very clear and simple explanation of the Dual Control Model using a stoplight analogy.
Please watch from 03:04 to 04:03. Focus on how the video defines the sexual excitation system (SES) as the 'green light' and the sexual inhibition system (SIS) as the 'red light'.
As the video explained, your level of arousal at any given moment is the result of the balance between these two systems. It's not just about what's pushing the accelerator; it's also about what's hitting the brakes. Both systems are constantly running in the background.
This "balance" concept is key. An excellent way to visualize it is as a tipping scale.
The Interplay: Why Releasing the Brakes is Key
A common mistake is to think that if you're not feeling aroused, you just need to press the accelerator harder—add more stimulation, watch more porn, try a new technique. While that can help, the Dual Control Model shows us that it's often more effective to first focus on releasing the brakes.
Imagine trying to drive a car with one foot on the gas and the other on the brake. You won't go very far, and you'll burn out the engine. The same is true for sexual arousal.
Let's watch one more short clip that explains this interplay with that exact analogy.
How to Deal With Desire Discrepancy: 8 Tips for Couples | Sex Therapist Explains
In this clip, sex therapist Lauren Consul uses Emily Nagoski's framework to explain the interplay between accelerators and brakes.
Please watch from 04:14 to 05:15. Pay attention to the examples of accelerators and brakes, and the car analogy she uses to describe their interaction.
As you can see, accelerators and brakes can be anything.
- Common Accelerators (SES Triggers): A specific kind of touch, feeling desired by a partner, a romantic setting, a particular scent, an erotic fantasy.
- Common Brakes (SIS Triggers): Stress about work or money, body image anxiety, feeling emotionally disconnected, a messy room, fear of being overheard.
Two Types of Brakes: A Deeper Look
Your background in research might lead you to appreciate that the model has more nuance. The "brakes" (SIS) aren't just one monolithic system. The original research by Janssen and Bancroft identified two distinct types of sexual inhibition.
Come As You Are by Emily Nagoski - ArtySana
This document is a summary of Emily Nagoski's book 'Come As You Are,' which is based on the Dual Control Model. It provides a clear, accessible breakdown of the two types of brakes.
Please read the first five paragraphs under the heading 'Arousal.' Focus on the distinction between the 'footbrake' (fear of performance consequences) and the 'handbrake' (fear of performance failure).
To summarize and formalize these concepts from the original scientific literature:
-
SIS1: Inhibition due to Threat of Performance Failure. This is the "handbrake" Nagoski refers to. It's about internal threats and anxieties. It's the voice in your head asking, "Will I be able to get/stay aroused?" "Will I have an orgasm?" "Am I being a good lover?" For many people, this is a very powerful brake.
-
SIS2: Inhibition due to Threat of Performance Consequences. This is the "footbrake." It's about external threats in the environment. It's activated by concerns like "Could we get caught?" "Is there a risk of STIs or pregnancy?" "What will my partner think if I suggest this?" "Is my phone going to ring?"
Distinguishing between these two types of brakes is incredibly useful. If you or a partner are struggling with arousal, you can ask: Is the brake an internal worry about performance (SIS1), or an external concern about the situation (SIS2)? Addressing SIS1 often involves mindfulness, self-compassion, and reassurance, while addressing SIS2 involves changing the physical or emotional environment to increase safety and reduce distractions.
Individual Differences and Changing the Context
Crucially, the Dual Control Model emphasizes individual variability. We are all "wired" differently.
- Some people have a very sensitive accelerator and less sensitive brakes. They get turned on easily and in a wide variety of contexts.
- Some people have very sensitive brakes (either SIS1, SIS2, or both). They may need a very specific context of low stress, high safety, and emotional connection to become aroused.
These sensitivities are considered stable traits, much like personality traits. You can't simply decide to have a less sensitive brake system. However, this is not a life sentence for bad sex. The most empowering insight from this model is that while you can't easily change the mechanism, you can absolutely change the context the mechanism responds to.
Come As You Are by Emily Nagoski - ArtySana
Let's return to the summary of 'Come As You Are' to see how this works in practice.
Read the section under the heading 'CONTEXT.' Focus on the core idea: 'we may not be able to change the mechanism but we can change what the mechanism responds to.'
This is where the power lies. By understanding your own and your partner's accelerators and brakes, you can consciously engineer a context that hits more accelerators and, most importantly, releases the brakes. This is the practical application of the model and directly ties into the concept of creating a "pleasurable context" for responsive desire that we discussed in the last lesson.
Conclusion
Today, we've dissected the Dual Control Model of sexual response, moving from a simple "on/off" switch to a more dynamic model of balance and interplay.
Key Takeaways:
- Sexual response is governed by the balance between the Sexual Excitation System (SES - the accelerator) and the Sexual Inhibition System (SIS - the brakes).
- Arousal is not just about the presence of turn-ons, but the absence of turn-offs. Releasing the brakes is often the most critical step to increasing arousal.
- There are two distinct inhibitory systems: SIS1 (fear of performance failure/internal threats) and SIS2 (fear of performance consequences/external threats).
- Everyone has a unique sensitivity in their accelerator and brake systems. While these traits are stable, you can change the context to maximize accelerators and minimize brakes.
Preview of the Next Lesson
Now that we have this foundational model, we can explore some of the most powerful accelerators. In our next lesson, we will focus on one of the most significant: the human mind. The learning outcome will be to describe the role of fantasy, novelty, and erotic imagination in sustaining sexual engagement. We will see how these mental factors directly engage the Sexual Excitation System and how they can be cultivated to enhance desire and pleasure.