Of The Following Bodily Changes, Which Is Associated With The Stress Response?

Chronic activation of this survival mechanism impairs health

chronic stress

A stressful situation — whether something environmental, such as a looming work deadline, or psychological, such as persistent worry nearly losing a job — can trigger a cascade of stress hormones that produce well-orchestrated physiological changes. A stressful incident can make the heart pound and breathing quicken. Muscles tense and beads of sweat appear.

This combination of reactions to stress is also known as the "fight-or-flying" response because it evolved equally a survival mechanism, enabling people and other mammals to react quickly to life-threatening situations. The carefully orchestrated yet near-instantaneous sequence of hormonal changes and physiological responses helps someone to fight the threat off or flee to safety. Unfortunately, the body tin also overreact to stressors that are non life-threatening, such every bit traffic jams, piece of work pressure, and family difficulties.

Over the years, researchers have learned non only how and why these reactions occur, but have also gained insight into the long-term effects chronic stress has on physical and psychological health. Over fourth dimension, repeated activation of the stress response takes a toll on the body. Research suggests that chronic stress contributes to high blood pressure, promotes the formation of artery-clogging deposits, and causes brain changes that may contribute to anxiety, depression, and addiction.. More preliminary inquiry suggests that chronic stress may besides contribute to obesity, both through direct mechanisms (causing people to eat more) or indirectly (decreasing slumber and practice).

Sounding the alarm

The stress response begins in the brain (see analogy). When someone confronts an oncoming car or other danger, the optics or ears (or both) send the data to the amygdala, an area of the encephalon that contributes to emotional processing. The amygdala interprets the images and sounds. When it perceives danger, it instantly sends a distress betoken to the hypothalamus.

Command center

illustration of brain showing areas activated by stress

When someone experiences a stressful event, the amygdala, an area of the brain that contributes to emotional processing, sends a distress signal to the hypothalamus. This expanse of the brain functions like a command center, communicating with the rest of the body through the nervous system so that the person has the energy to fight or flee.

The hypothalamus is a fleck like a command middle. This area of the encephalon communicates with the remainder of the body through the autonomic nervous system, which controls such involuntary body functions as animate, blood pressure, heartbeat, and the dilation or constriction of key blood vessels and small airways in the lungs called bronchioles. The autonomic nervous organization has two components, the sympathetic nervous system and the parasympathetic nervous system. The sympathetic nervous system functions similar a gas pedal in a car. Information technology triggers the fight-or-flying response, providing the trunk with a burst of energy so that it can reply to perceived dangers. The parasympathetic nervous system acts similar a restriction. It promotes the "rest and digest" response that calms the body down later the danger has passed.

After the amygdala sends a distress betoken, the hypothalamus activates the sympathetic nervous arrangement past sending signals through the autonomic nerves to the adrenal glands. These glands respond by pumping the hormone epinephrine (also known equally adrenaline) into the bloodstream. As epinephrine circulates through the body, it brings on a number of physiological changes. The heart beats faster than normal, pushing claret to the muscles, centre, and other vital organs. Pulse rate and claret pressure level go upwardly. The person undergoing these changes also starts to breathe more rapidly. Small-scale airways in the lungs open broad. This way, the lungs can take in every bit much oxygen equally possible with each breath. Extra oxygen is sent to the brain, increasing alertness. Sight, hearing, and other senses become sharper. Meanwhile, epinephrine triggers the release of blood carbohydrate (glucose) and fats from temporary storage sites in the trunk. These nutrients flood into the bloodstream, supplying energy to all parts of the torso.

All of these changes happen so quickly that people aren't enlightened of them. In fact, the wiring is and then efficient that the amygdala and hypothalamus start this cascade even before the brain's visual centers have had a take a chance to fully process what is happening. That'southward why people are able to jump out of the path of an oncoming auto even before they think near what they are doing.

Equally the initial surge of epinephrine subsides, the hypothalamus activates the second component of the stress response organisation — known as the HPA axis. This network consists of the hypothalamus, the pituitary gland, and the adrenal glands.

The HPA centrality relies on a serial of hormonal signals to keep the sympathetic nervous system — the "gas pedal" — pressed down. If the brain continues to perceive something as dangerous, the hypothalamus releases corticotropin-releasing hormone (CRH), which travels to the pituitary gland, triggering the release of adrenocorticotropic hormone (ACTH). This hormone travels to the adrenal glands, prompting them to release cortisol. The body thus stays revved upward and on high alert. When the threat passes, cortisol levels fall. The parasympathetic nervous system — the "brake" — then dampens the stress response.

Techniques to counter chronic stress

Many people are unable to detect a manner to put the brakes on stress. Chronic low-level stress keeps the HPA axis activated, much similar a motor that is idling too high for likewise long. After a while, this has an consequence on the torso that contributes to the health bug associated with chronic stress.

Persistent epinephrine surges can harm blood vessels and arteries, increasing blood pressure and raising risk of heart attacks or strokes. Elevated cortisol levels create physiological changes that help to replenish the torso's energy stores that are depleted during the stress response. But they inadvertently contribute to the buildup of fat tissue and to weight gain. For example, cortisol increases ambition, so that people volition want to consume more to obtain extra free energy. It also increases storage of unused nutrients as fatty.

Fortunately, people tin learn techniques to counter the stress response.

Relaxation response. Dr. Herbert Benson, managing director emeritus of the Benson-Henry Institute for Mind Trunk Medicine at Massachusetts General Hospital, has devoted much of his career to learning how people tin can counter the stress response past using a combination of approaches that elicit the relaxation response. These include deep abdominal breathing, focus on a soothing word (such equally peace or at-home), visualization of tranquil scenes, repetitive prayer, yoga, and tai chi.

Most of the research using objective measures to evaluate how effective the relaxation response is at countering chronic stress have been conducted in people with hypertension and other forms of heart disease. Those results propose the technique may be worth trying — although for most people it is not a cure-all. For example, researchers at Massachusetts General Hospital conducted a double-blind, randomized controlled trial of 122 patients with hypertension, ages 55 and older, in which half were assigned to relaxation response training and the other half to a control grouping that received information virtually blood pressure control. Later 8 weeks, 34 of the people who skillful the relaxation response — a piffling more than half — had accomplished a systolic blood pressure reduction of more than v mm Hg, and were therefore eligible for the next phase of the written report, in which they could reduce levels of blood pressure medication they were taking. During that 2d stage, 50% were able to eliminate at least one blood pressure medication — significantly more than in the control group, where only 19% eliminated their medication.

Physical action. People tin use do to stifle the buildup of stress in several ways. Exercise, such equally taking a brisk walk shortly after feeling stressed, non only deepens breathing but likewise helps relieve musculus tension. Movement therapies such equally yoga, tai chi, and qi gong combine fluid movements with deep animate and mental focus, all of which tin can induce calm.

Social support. Confidants, friends, acquaintances, co-workers, relatives, spouses, and companions all provide a life-enhancing social cyberspace — and may increment longevity. It's not clear why, simply the buffering theory holds that people who bask close relationships with family and friends receive emotional support that indirectly helps to sustain them at times of chronic stress and crisis.

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