The Stress Response

Stress is an incredibly complex and immediate whole-body response to a perceived or real threat. I’ll say that again because it’s a very important point; the body doesn’t differentiate between what is real or imagined. Thus, if you are in a state of continual stress about threats (real or imagined), your body will deal with them in the same way.

The stress mechanism or the emergency response process, in its infinite wisdom, is designed to get our body ready to defend itself, by fight, flight or freeze.

In times long past you can imagine a scenario where a sabre tooth tiger or some such menace was sizing you up for its meal. Your body, perceiving this threat, readied itself for fighting of flight (but hopefully in this case – not freeze!). Once you had defended your territory or run off to safety, your body had a chance to return to a pre-stress, pre-sabre tooth tiger state of normal homeostasis.

Now consider today’s society. Your boss has just demanded you work back an extra hour to finish off a report that was only given to you yesterday (and should have been given to you over a week ago), you can’t do the overtime because you have just been called by the school to come and pick up one of your children who has fallen sick. Once home you have a mountain of paperwork to do, dinner to cook, emails to return, children to attend to. And you go over and over and over the day’s events. In fact, you feel very stressed long after things have somewhat settled down. You can’t sleep, so you start the following day at less than optimal capacity ready for another onslaught of demands.

Modern day life and the multitude of opportunities to experience stress can result in us experiencing difficulty returning to a normal (less-stressed) state. Basically, we lived in a hyped-up state, “on-line” far past the initial event.

Now some stress is important and vital for us to maintain momentum in our life. However, a continued state of stress, over a long period of time, can lead to many health concerns. When we are stressed, our body can’t renew or detoxify our cells – basically we age quicker.

However, recent research has shown that how we view stress is vital to its effects on us.

In a very interesting talk by Health Psychologist Kelly McGonigal on TED September 2013, she explained how to make stress your friend.

In a study tracking 30,000 adults in the United States over eight years, the people who experienced a lot of stress in the previous year had an increased risk of dying – ONLY if they believed that stress is harmful for their health. The people who experienced a lot of stress but did not view the stress as harmful where no more likely to die.

When you change your mind about stress, you can change your body’s response to stress.

In another study, participants were taught to rethink their stress response as helpful and then given a stress test. The participants who learned to review the stress response as helpful were less stressed out, less anxious and more confident. What this study also determined was that this belief also affected the physiology of their body. Instead of their blood vessels constricting when their heart rate increased, their blood vessels stayed relaxed. Their heart was still pounding, but their blood vessels were not constricted.

Part of the stress response is the release of the hormone called oxytocin. Your pituitary gland releases oxytocin which acts on multiple levels. It acts on your brain, stimulating your need to seek support and be more social. It makes you crave physical contact with family and friends, while also enhancing your empathy, making you more willing to help and support the people you care about.

The release of oxytocin when stressed makes you social.

Oxytocin also acts on the heart, protecting your cardiovascular system from the effects of stress. It is naturally anti-inflammatory and helps your blood vessels stay relaxed during stress. Oxytocin also helps the heart cells regenerate and heal from any stress-induced damage. These physical benefits of oxytocins are enhanced by social contact and support.

“…when you reach out to others under stress, either to seek support or to help someone else, you release more of this hormone, your stress response becomes healthier, and you actually recover faster from stress…. your stress response has a built-in mechanism for stress resilience, and that mechanism is human connection.”

“How you think and how you act can transform your experience of stress. When you choose to view your stress response as helpful, you create the biology of courage. And when you choose to connect with others under stress, you can create resilience.”

Kelly McGonigal

For the full video and transcript, you can view the article here (14 minutes 29 seconds)

So how does the Stress Mechanism Work?

(Reference: Matrix Reimprinting)

For those who want a more technical (but not definitive) understanding of the stress response then read below. What I hope you really get from this explanation is how VAST and complex the stress response is, and how many of the body parts come in to play. Stress really is a whole-body response.

The body responds physiologically to stress through a system known as the hypothalamus-pituitary-adrenal (HPA axis).

→ Threat perceived (real or imagined).

→ Message sent to thalamus (cluster of cells in the middle of the brain which forms a relay station for messages between the brain and the body).

→ Thalamus then sends information to various areas of the brain, one of which is the amygdala (a group of nerve cells that processes memory and emotional reactions), and the amygdala attaches an emotional meaning to the information.

→ Information then sent to hippocampus (centre of processing conscious memory).

→ Hippocampus forms a conscious structure for the threat-base information.

→ Information sent to the orbitofrontal cortex, which evaluates the threat for severity and either heightens or tones down our survival behaviour.

→ If the information is deemed by the orbitofrontal cortex to be a threat it activates the hypothalamus.

→ Hypothalamus perceives threat and engages HPA axis by sending signal to the pituitary gland.

→ Pituitary gland sends message to the adrenal glands, stimulating fight/flight response. Stress hormones (e.g. adrenaline and cortisol) released into the blood.

 Physiological Changes of the Fight/Flight Response

  • Heart rate increases
  • Blood pressure increase as the coronary arteries dilate
  • Respiratory rate increases
  • Muscle tension increases
  • Hormones such as adrenaline, noradrenaline, cortisol, oxytocins and vasopressin are released into the bloodstream
  • Hydrochloric acid is secreted into the stomach
  • Glucose is released from the liver
  • Basal metabolic rate increases
  • Blood leaves the forebrain and digestive tract and moves into the muscles and limbs, launching body into action
  • Pupils dilate – improving eyesight
  • Systems not essential for fight or flight (immune, digestive, sexual) virtually shut down

Psychological Consequences of Stress

  • Ability to maintain perspective diminishes significantly as do other logical functions. When stress sends you into flight/flight, up to 80% of the blood leaves your forebrain and goes into your arms and chest to fight, or into your legs to run. Your ability to use the logical part of your brain effectively shuts down reducing your chances of seeing other possible solutions.
  • Increases the tendency to rely on instinctive or habitual stress-induced behaviour patterns rather than seeing a more creative response.
  • Anger/rage can accompany and support the fight response. One study found that anger compromises the immune system by decreasing Immunoglobulin A (first line of defence of the immune system) and simply recalling any angry experience caused a six-hour suppression of the immune system.
  • Fear/panic can accompany and support the flight response.
  • Hysteria/overwhelm/numbness can result if the fight/flight response is activated but then inhibited, or not acted upon.

The Adrenal Glands and their Role in Stress

The adrenal glands are two tiny glands that sit on top of the kidneys. They may be tiny, but they are incredibly important and form part of the endocrine (glandular) system. They are the body part responsible for regulating our response to stress through the excretion of hormones such as cortisol and adrenaline. Adrenalin is produced as your first reaction to a crisis. Cortisol affects your immune system and blood sugars amongst other functions. Adrenal exhaustion through the continued excretion of these hormones (amongst others) from ongoing stress can cause a multitude of health concerns.

Some Adrenal Gland facts

  • The more often you activate adrenaline via the adrenals, (i.e. the more stressed you are), the higher the levels of cortisol in body (which is damaging).
  • If the adrenals are making cortisol, they aren’t making dehydroepiandrosterone (DHEA), which is responsible for many of the health-promoting and protective functions of the body.

Low DHEA in the body can manifest as:

  • Decreased cell repair and regeneration affecting healthy cell function
  • Low testosterone and oestrogen production affecting fertility
  • Bone loss
  • Increased cholesterol and LDLS inflammatory areas
  • Increased fat deposition
  • Insomnia – wired but can’t sleep
  • Anxiety

High levels of cortisol give rise to:

  • Increased fat (e.g. a cortisol pouch on the stomach)
  • Reduced memory and learning ability
  • Is linked to bone loss and reduced muscle mass

When stress levels have been very high over a long period of time, the production of cortisol decreases. Low cortisol can show as:

  • Chronic fatigue
  • Depression
  • Anorexia
  • PMS
  • Early menopause
  • Fibromyalgia
  • Impotence
  • Infertility

The rest of this website is designed to provide options that you can use to help lower your stress levels.

However, please use common sense and consult your health professional for all your health matters.  This website is a guide only and is not a substitute for expert medical advice.