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When stress takes over

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Published the 10/24/2020

Everyone experiences moments of stress in their life. It is an important element for the survival of man and animals. However, in our modern society, certain responses of our body to stress can cause more harm than benefits, such as heart attacks, diabetes or even reduced immune functions … An adequate balance between time of stress and hormone production regulating is important. Two types of stress are known: acute stress and chronic stress.

The acute stress is the one that allows us to survive. This results in a so-called adaptive response, specific to the stress caused. This reaction stages different actors. Neurotransmitters, which correspond to chemical molecules, allow the transmission of messages between neurons. Neuropeptides are used to modulate the transmission of information between neurons. And hormones, which are molecules circulating in the body to stimulate specific cells.

Long-term chronic stress deregulates the stress system and is toxic. It can thus lead to several pathologies.

During a stress, there are two actors: the stressor, the factor causing the stress itself, and the stress defined by the biological cascade caused by this event.

After numerous studies and definitions, stress is characterized by a mechanism that is both psychological and biological. The stressor acts on a learning process and the emotional part of the individual.

An unforeseeable event or one perceived as a threat can lead to acute stress. The signal is first picked up by the amygdala where various hormones like dopamine, acetylcholine, serotonin and norepinephrine will be released, to be redirected to the adrenal glands and sympathetic terminal nerves. At this level, there will be a secretion of adrenaline, noradrenaline and cortisol towards different areas of the brain. This enables emotional arousal, increased alertness and information processing.

Diagram of the biological response linked to a stressor during acute stress

In parallel, the stress hormones will increase the force of contraction of the blood vessels, the blood pressure and the respiratory rate, and thus provide for the need for behavioral responses related to stress (flight, combat, etc.).

Stress hormones will also increase immune defenses, but also slow down functions not essential to survival, such as digestion. These biological changes are limited in time so as not to harm the organism.

The normal state of balance at the molecular level will be restored by the action of cortisol and catecholamines acting on the brain. This secretion also allows the storage of useful information for a future exposure to the same stressor.

In a state of chronic stress, the permanence of this prevents a return of the «level» of hormones to normal. The excess of these hormones is harmful and creates a vicious circle. Among the undesirable effects linked to a prolongation of stress hormones, we find: a «decrease in the efficiency» of the immune system, atrophy of the muscles as well as of the neurons, diabetes, depression, impaired attention and memory of learning, and an increase in that of fear.

Diagram of the hypotheses concerning the impacts of chronic stress.

In the case of a traumatic situation, corticosteroids and catecholamines are secreted in particular. These hormones «regulate» our ability to store and restore acquired information. Under these conditions, the traumatic event is more easily recorded in the memory, unlike elements which are not linked to it.

Stress almost always generates a specific emotion.

Emotions and stress share important characteristics. Stress can be felt during an emotion, such as the sadness of having missed your exam usually accompanied by stress.

Stressful emotional experiences often lead to many psychological and physical problems. These experiences can have an impact on our memory such as forgetting an important meeting. For this reason, we tend to take the negative effects of stress more into account than the positive effects on our memory. Indeed, stress helps to better retain the causes causing it and thus better prepare for it for the next time.

In our society where the pace of life is very fast with high demands and global economic competition, stress occupies a prominent place. A lack of rest and an overdose of stress thus cause burn out, depression, headache, but also muscle pain, disorders that are regularly found during sick leaves. According to the American Institute of Stress, as many as a million workers are on sick leave every day from the consequences of stress, which has a strong economic impact. On the UK side, according to the Health and Safety Executive, in 2018/2019, stress, depression or anxiety would represent 44% of all cases of poor work-related health and 54% of everyday working days lost due to ill health.

Diagram of the causes of stress according to the American Institute of Stress.

In view of recent events and the increase of remote working, it appears that many employees would prefer to continue their activities at home. The main reasons mentioned are transport times, avoidance of possible delays and traffic jams and above all the scheduling. Some even say they are less stressed. We can therefore wonder if the vision of work will change to tend towards more frequent teleworking and thus perhaps reduce the dose of stress with which workers are confronted.

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