Work interviews, tight deadlines, final exams, traffic jams—our everyday lives are full of potentially stressful situations. We all experience stress from time to time. And we know that stress is more than just an emotion. It can affect our whole body. When we feel stressed, our heart starts pounding faster, blood pressure rises, and our senses sharpen.
What exactly is stress and why do we respond to it this way? In this article, you’ll learn about the stress response, including things that may make someone stressed and the physiological reactions to stress.
What is Stress?
Stress is the emotional and physical tension that occurs when we feel incapable of dealing with what we perceive as a threatening situation. The combination of physiological changes that occur when we face a stressor, like a barking dog or oncoming car, is the stress response.
In emergencies, the stress response gives us the energy to react or defend ourselves. It allows us, for example, to quickly slam on the brakes to avoid a car accident.
Let’s see what is the mechanism behind the stress response.
What Happens During a Stress Response?
The stress response begins in the brain. When we perceive a situation as stressful, the amygdala—the area of the brain that contributes to emotional processing—sends a distress signal to the hypothalamus. The hypothalamus is a small region at the base of the brain that plays an essential role in hormone production.
When the stress response is triggered, the hypothalamus prompts the adrenal glands to release adrenaline into the bloodstream. Adrenaline causes a number of physiological changes such as increased metabolism, blood pressure, heart and breathing rates. All these changes prepare us to deal with stress. They improve our strength and stamina, speed up our reactions, and enhance our focus. We are now ready for what is known as a fight or flight response.
The fight-or-flight response or acute stress response is the reaction of the body to danger. It is the body’s way of keeping us safe.
After the initial stage, the adrenal glands start releasing cortisol, a hormone that ensures that the body remains alert until the danger has passed. As the level of cortisol gradually falls, the stress response decreases and the body returns to its pre-stress state.
Stress Response Stages
In 1946, Hungarian-Canadian endocrinologist and “the father of stress research” Hans Selye, developed the general adaptation syndrome (GAS) theory in which he introduced stress response stages. Selye argues that when we find ourselves in a stressful situation our body goes through three distinct physiological responses to stress.
The alarm stage consists of the initial symptoms that we experience under stress. The fight-or-flight response, our immediate reaction to stress, occurs in this stage. When exposed to a stressor, we undergo several biological changes and are ready to take action.
At the resistance stage, our body attempts to re-establish a balance. It starts adapting to stress by decreasing activity and conserving energy. We feel calmer and the body’s physiological functions return to normal—our heart rate slows down and blood pressure begins to normalize.
Although the body has entered a recovery phase, it remains on high alert. If we no longer perceive the situation as dangerous, the body will continue to repair itself until our hormone levels, heart rate, and blood pressure reach their pre-stress states.
However, certain stressful situations can last for extended periods of time. If we are not able to resolve them quickly and our body remains on alert, we will enter the exhaustion stage.
Exposure to stress for long periods can drain our physical, emotional, and mental resources, leaving us with no energy to fight stress. This is when long-term psychological changes start taking place. These changes can cause symptoms such as depression, sleep deprivation, and anxiety.
The exhaustion stage is caused by prolonged or chronic stress.
What is Chronic Stress?
If we remain in a heightened state of stress over longer periods, in situations such as financial problems, sudden job loss, divorce, or exams, for example, the stress response can become harmful. The condition in which the body has difficulties returning to its normal state is called long-term or chronic stress. Responses to chronic stress can be of both physical, emotional, and behavioral nature:
- Physical responses include low energy, dizziness, stomach cramps, insomnia, headache, nausea, weight loss, and sweating.
- Emotional responses manifest themselves as restlessness, agitation, depression, anger, nightmares, mood swings, anxiety, social inhibition, and forgetfulness.
- Behavioral responses to stress may appear to be bad habits: smoking, excessive spending, nail-biting, fidgeting, and aggressivity.
Chronic stress can suppress the immune system and cause serious health problems in the long run. Consistently elevated levels of stress hormones increase the risk of heart attack and stroke, and make us vulnerable to mental health problems.
The stress response depends largely on our perception of a situation. While some people are terrified of speaking in front of an audience and develop a stress response, others like being in the spotlight and remain perfectly calm before they take the podium.
The intensity of the stress response is related to the level of perceived threat rather than an actual threat.
The way we respond to stress is extremely important. If we believe that a stressful situation is a challenge that can be controlled, we have more chances of avoiding chronic stress and remaining healthy. Fortunately, it is possible to improve the ability to deal with difficult situations and control the stress response.
One of the ways of doing this is replacing the stress response with the relaxation response.
Who Discovered the Relaxation Response?
The term relaxation response was coined in 1975 by cardiologist Dr. Herbert Benson. The relaxation response is the opposite of the fight-or-flight response. It is a way to encourage the body to release chemicals that make muscles and organs slow down. It allows us to turn off the stress response and return our body to a pre-stress state.
Benson suggests a range of tools and strategies that can be used to successfully revert the effects of the stress response. They include deep abdominal breathing, focus on soothing word repetition, visualization, prayer, tai-chi, and yoga.