Most of us know about the “fight or flight” response, the body’s built-in survival instinct. But that framework leaves out two other common ways the nervous system reacts to stress.

Indeed, psychologists say there are four instinctive reactions that help us understand how people cope with feeling unsafe, overwhelmed or emotionally flooded.

“The ‘four F’s’ – fight, flight, freeze and fawn – refer to automatic nervous system responses to a perceived threat,” Caitlyn Oscarson, a licensed marriage and family therapist, told HuffPost. “These are ingrained responses that can show up in traumatic situations, as well as everyday stress and overwhelm.”

The four stress responses occur when our bodies are in survival mode, so we aren’t using the reasoning centre of our brains. Thus, we may act in ways that don’t seem logical or reflective of our typical values.

“They’re not personality traits, and they’re not conscious choices,” said board-certified psychiatrist and Practical Optimism author Dr. Sue Varma. “They’re automatic survival strategies wired into the brain and body. When someone feels unsafe, overwhelmed or emotionally flooded, the nervous system steps in and tries to protect them the best way it knows how.”

In this sense, your stress response can offer insight into your past experiences and what your nervous system learned over time to keep you emotionally or even physically safe. Most people don’t have just one response, and their automatic reaction might vary based on context. You might fawn at work but freeze at home, for instance.

“All four responses are adaptive,” Varma said. “They develop for a reason, often early in life, and they’re attempts at self-preservation, not signs of weakness. It is interesting, however, to note if a person has a particular go-to response, that is very telling.”

Although you might have one or two default stress responses in different situations, you ultimately want to work on flexibility to gain access to all four because each can serve a purpose at various times. No one stress response is inherently better or worse. The goal is to help your nervous system understand it has options.

“An individual’s stress response is not their personality but rather their nervous system’s autobiography, and like with any life narrative, it can be changed to have more options to address stressful situations,” said Lora Dudley, a licensed clinical social worker with Thriveworks.

Fight, flight, freeze and fawn are not character flaws, and with mindfulness and therapy, you can learn to choose and be more flexible with your responses. Ultimately, awareness is the first step.

“Once you understand your patterns and how they are tied to your nervous system response, it becomes easier to slow down, be compassionate toward yourself and act with intention rather than reflexively,” Oscarson said.

With that in mind, HuffPost asked the experts to break down each of the four stress responses, how they manifest and what someone’s defaults might say about them.

“In my patients, the fight response often shows up as anger, irritability, defensiveness or a strong need to control a situation,” Varma said. “Someone might argue more, push back quickly or feel constantly on edge when they’re under stress.”

There can be physical aggression and tension but also yelling and argumentativeness in moments of disagreement or stress.

“This is the ‘come at me’ response,” said Erin Pash, a licensed marriage and family therapist and founder of Pash Co., a company focused on social health.

“You might notice yourself getting argumentative, defensive or aggressive. Your jaw clenches, your voice gets louder, you feel heat in your chest. In everyday life, this might look like snapping at your partner over something minor, getting road rage or having a disproportionate reaction to feedback at work.”

So what might it say about you if you lean toward confrontation and feel the urge to argue and defend yourself when you feel misunderstood?

“For fight responses, it doesn’t necessarily mean that a person is aggressive or violent,” Oscarson said. “It means that their nervous system activates under threat, and they have learned that taking action is necessary for self-protection. Pushing back, arguing and taking control are ways of creating order in chaos and stress.”

She added that fight-inclined individuals might have a strong sense of justice and fairness and even leadership skills. Past experiences may have taught them that the way to feel safe is to stay alert, push back and stand your ground.

“Maybe you grew up in an environment where you had to defend yourself or your boundaries aggressively, or where conflict was how things got resolved,” Pash said. “The challenge is when this response fires in situations that don’t actually require battle mode.”

“Flight is characterised by attempts to escape from a threatening situation,” Oscarson said. “It may show up as passiveness, distractedness or avoidance.”

She gave the example of putting off or deflecting emotional conversations.

“You might cancel plans, ghost people, stay ‘too busy’ to deal with difficult conversations or develop sudden urgent tasks when conflict arises,” Pash said. “Physically, you might feel restless, unable to sit still or like you need to run.”

Therapist Natalie Moore compared the way this response manifests in modern human civilisation to how it plays out in the animal world.

“In the wild this looks like actual running, whereas in modern times this manifests as emotional running away – such as ghosting a friend who hurt your feelings, turning away from intimacy in a relationship or running away from your problems through avoidance behaviours like addiction or emotional numbing,” she said.

Those who lean into flight mode might also need constant distractions like screens or video games.

“With a flight response, an individual will try to escape the situation both internally and externally,” said psychologist Doreen Dodgen-Magee. “They may appear to deny what is happening, avoid conflict and the direct expression or working through of big feelings and may be anxious and fearful.”

They might also become hyperproductive.

“I see this in people who stay busy, overwork, overplan or distract themselves constantly,” Varma said. “Sometimes it’s literal leaving, and sometimes it’s mental checking out.”

Social isolation and withdrawing from everyday life can also be signs of a flight response.

“People who tend toward flight have learned that anticipating and avoiding conflict is the best way to stay safe,” Oscarson noted. “They may use productivity and business to keep others at a distance. They appear hardworking and responsible, which is often admired and praised. They also tend to be independent and self-sufficient.”

If this is your instinct, it might be because your nervous system learned that escape or avoidance was an effective survival strategy.

“This can develop when leaving or avoiding actually did make you safer, or when engagement led to worse outcomes,” Pash said. “It’s often paired with anxiety and hyper-vigilance – always scanning for exits and threats.”

“To freeze would be to shut down such as by going numb, dissociating or being indecisive,” said Hallie Kritsas, a licensed mental health counsellor with Thriveworks.

Essentially, your nervous system hits pause or shuts down in stressful or trauma-fuelling moments.

“You can’t think clearly, can’t speak up, feel paralysed in decision-making,” Pash said. “People often describe feeling like a deer in headlights – their mind goes blank, they dissociate or they become physically immobile. This might manifest as procrastination, shutting down during arguments or going numb when overwhelmed.”

They might feel low motivation or a sense of being “stuck,” which makes it hard to start a task. It might even seem like they don’t care what’s happening.

″‘Freeze’ can be presented in feeling stuck, numb, inability to act or speak with the purpose being to pause or be unnoticed when there is not a manner to escape the threat,” Dudley said.

The freeze response is very common and often misunderstood, Varma noted, adding that it tends to be a sign of nervous system overload.

“I often see people who experienced overwhelm without enough support,” she explained. “Shutting down became the body’s way of coping when there were no good options available. These individuals are often deeply sensitive and strongly affected by their environments.”

When fighting back or escaping a stressful situation isn’t safe or possible, people often freeze as a way to conserve energy in their state of powerlessness and overwhelm.

“Freeze often develops when we faced threats we couldn’t fight or flee from – particularly in childhood when we were smaller and dependent on adults who were also the source of threat,” Pash said. “It’s also common in people who were punished for showing emotion or who learned that their reactions ‘made things worse.’”

“Fawn is the one many people don’t recognise in themselves right away,” Varma said. “It shows up as people-pleasing, over-accommodating, minimising your own needs or trying to keep the peace at all costs. I see this a lot in people who are highly empathetic and tuned in to others’ emotions.”

With fawning, people tend to over-apologise, agree on things they don’t actually agree with and abandon their boundaries. There’s a sense of passiveness as they prioritise others’ needs and emotions and sacrifice their own.

“An example of fawning is feeling responsible for managing other people’s emotions,” Oscarson said.

Those who fawn may have learned that safety depends on keeping others happy or calm.

“Maybe you grew up walking on eggshells around someone’s mood, or you learned that your needs didn’t matter as much as maintaining peace,” Pash said. “Fawning is incredibly common in people who experienced childhood emotional neglect or had caregivers with big emotions they had to manage.”

With fawners, being “low maintenance” or minimising yourself feels like the way to keep the peace, which is the key to emotional and/or physical safety.

“Many of these patients learned early on that maintaining harmony or avoiding conflict protected them from rejection or emotional fallout,” Varma said.

The idea is to be helpful, agreeable or “easy” to others.

“If one fawns, they have learned that safety comes from seeking approval,” Kritsas echoed.

Consequently, they might have learned to be highly intuitive and sensitive to social cues.

As Oscarson put it, “they probably have a hard time when someone is upset with them or disagrees with them, as they view any misalignment as threatening to the relationship and therefore their safety”.