Fight-or-Flight Response

10 Key excerpts on "Fight-or-Flight Response"

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  Stress Management for Life

  A Research-Based Experiential Approach

  • Michael Olpin, Margie Hesson, Michael Olpin(Authors)
  • 2020(Publication Date)
  • Cengage Learning EMEA

    (Publisher)

  The cascade of nervous system activity and release of stress hormones cause immediate physiological responses that help a person deal with or avoid danger by either fighting or running. Harvard physiologist Walter Cannon coined the term fight-or-f light response to describe the body’s automatic response anytime we perceive a threat or danger. This primi- tive response gives us extra strength, power, and speed to avoid physical harm. As you read in Sarah’s story in the opening vignette, the Fight-or-Flight Response can be activated to protect both others and us when we perceive danger. The Fight-or-Flight Response is designed to help us do one thing, and only one thing: survive physical danger! Physiologically, the stress response is characterized by activation of the sympathetic nervous system, which results in the secretion of chemicals into the blood- stream, mobilizing the behavioral response. Whether the reaction culminates in “fight” or “flight” depends on whether we perceive the threat or stressor as surmountable or insur- mountable. Consequently, a stress response that works as it is designed is essential to sur- vival. Figure 3.1 illustrates the Fight-or-Flight Response. Because we are designed for survival, our body systems react to protect us from pain and death in life-threatening or dangerous situations. In the short run, this response is a power- ful and useful process. Scientists use the term homeostasis (homeo 5 the same; stasis 5 standing) to define the physiological and emotional boundaries at which the body functions efficiently and comfortably. Stress disturbs homeostasis by creating a state of imbalance. When we are in homeostasis, we are in a state of balance. We disrupt the balance when something happens in our surroundings—something equivalent to a bear rampaging out of the forest. This per- ception of danger automatically activates the Fight-or-Flight Response.

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  Equitation Science

  • Paul McGreevy, Janne Winther Christensen, Uta König von Borstel, Andrew McLean(Authors)
  • 2018(Publication Date)
  • Wiley-Blackwell

    (Publisher)

  Figure 13.1 The standard stress model. When the brain perceives a stressor, two main sets of physiological reactions prepare the body for bursts of exercise (‘fight or flight’) and activate a range of other reactions (e.g. reduced pain perception and immunological responses).

  The central nervous system assesses whether a stimulus represents a significant challenge to the animal. If it is perceived as threatening (i.e. a stressor), the biological defence consists of a combination of behavioural, autonomic and neuroendocrine stress reactions, and the individual is in a state of stress. The body’s immediate physiological reaction to a stressor is characterised by activation of the sympathetic system, which prepares the body for action. The fight or flight reaction of the sympathetic system is initiated by stimulation of the hypothalamus, which transmits signals via the reticular formation in the brain stem to the spinal cord to cause sympathetic discharge. This immediately results in several physiological changes, which lead to a greater physical and mental ability, so that the animal can perform more strenuous physical activity than would otherwise be possible (Korte, 2001). Sympathetic stimulation increases both the rate and force of the heart’s contractions, as well as arterial blood pressure. Blood flow is redirected, with the blood vessels constricting to supply less blood to non‐critical areas (e.g. the gut, which inhibits digestion) and more blood is directed to the skeletal muscles and the brain. The transmitter at the neuromuscular junction is noradrenaline, a close relative of adrenaline. These hormones and neurotransmitters prepare the body for bursts of physical exercise, for example, when about to flee from a threat (Sapolsky, 2002; 2004).

  The sympathetic system is counteracted and modulated by the parasympathetic system, where the actions are principally opposite to those of the sympathetic system. The parasympathetic system becomes active when the body is engaged in processes relating to general body maintenance, such as eating and ingesting food. It slows the heart and respiration rates, and stimulates digestion and growth. The normal state of rest is predominantly characterised by parasympathetic activity. In stressful situations, the parasympathetic activity decreases in favour of a higher sympathetic activity, enabling the animal to react appropriately (e.g. with flight).

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  False Alarm

  The Truth about the Epidemic of Fear

  • Marc Siegel(Author)
  • 2008(Publication Date)
  • Trade Paper Press

    (Publisher)

  Fear is more than a state of mind; it’s chemical. It is present in the circuitry of our brains, in the neurochemical exchanges between nerves. Fear is a physical reaction to a perceived threat. As long as the danger is direct and real, fear is normal and helps to protect us.

  When an individual feels threatened, fear revs up the metabolism in anticipation of an imminent need to defend oneself or flee. “Fight or flight,” or the “acute stress response,” was first described by Walter Cannon, an American physiologist, in the 1920s. Cannon observed that animals, including humans, react to threats with a hormonal discharge of the nervous system. There is an outpouring of vessel-constricting, heart-thumping hormones, including noradrenaline (norepinephrine) and adrenaline (epinephrine), followed by the steroid cortisol. The heart speeds up and pumps harder, the nerves fire more quickly, the skin cools and gets goose bumps, the eyes dilate to see better, and the brain receives a message that it is time to do something.

  We need to know when another animal is threatening to attack us in order to kill us and eat us. The fact that this particular threat doesn’t exist anymore outside of the darkest jungles doesn’t mean that fear can no longer be useful, as it is when we stand too close to the edge of a building or turn the wrong way down a one-way street. Triggers of fear involve sudden or dramatic changes in our environment, including dark, light, cold, heat, noise, isolation, or irritation. We react by getting ready, either to attack the source of our fear or to move away from it.

  But not all danger is palpable or immediate. Many of the things that scare us aren’t sudden, surprising, or matters of life or death. Fear has many guises. For every change of life there is a new set of concerns. For every milestone there is a transition, and fear and foreboding are normal aspects of making these transitions. They are the body’s way of cautioning us that the change may or may not be for the better.

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  The Body Bears the Burden

  Trauma, Dissociation, and Disease

  • Robert Scaer(Author)
  • 2014(Publication Date)
  • Routledge

    (Publisher)

  The immediate effects of the arousal neurotransmitter norepinephrine on the brain include increased alertness and focus, immediate enhancement of short-term memory, dilatated pupils, increased muscle tone, and divergence (outward movement) of the eyes to expand the field of view. The immediate effects of body-based epinephrine and brain-based norepinephrine prepare the organism for the high-level neuromuscular activity required for ensuring survival in the face of threat—the fight/flight response. These effects promote short-term preparation of the brain for intense alertness, and the neuromuscular and cardiovascular systems for high-level short-term skeletal muscle and cardiac activity and energy expenditure. Activation of the fight/flight response, of course, may be triggered by excitement as well as by threat.

  FIGURE 2.2 Hypothalamic/pituitary/adrenal axis. Sensory input signaling stress or threat (see Figure 2.1 ) activates the hypothalamus, triggering release of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP). These promote release of cortisol from the adrenal medulla. Cortisol inhibits further release of ACTH, modulates the basic noradrenergic arousal response, and mediates the long-term stress adaptation response to stress.

  The basic physiological sympathetic nervous system response of the prey in response to threat is mirrored by that of the predator as it prepares for attack. Pre-game jitters, stage fright, sexual arousal, and the thrill of the roller coaster ride all reflect the physical sensations associated with arousal in the face of threat. What separates the experience of the fight/flight response from that of anticipatory excitement, of course, is the meaning of the event to the participant. This piece of information processing takes place in the hippocampus (comparison of new information with past associative memories), and the orbitofrontal cortex (problem solving and planning).4

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  Body Awareness Workbook for Trauma

  • Yau, Julie Brown(Authors)
  • 2019(Publication Date)
  • Reveal Press

    (Publisher)

  Connection with others who are safe, with whom we can engage, allows us to stay present even during a crisis or traumatic event. Of course, in a frightening situation there may not be someone close by who is safe. Sometimes the person who is meant to be safe is actually hurting you. Your next line of defense is to call for help. This response is connected to your sympathetic nervous system (SNS) and the panic circuits of your brain. If no one safe arrives, your innate flow of defenses then prepares you to flee. In this state of hyperarousal, the fear circuits of your brain are recruited to help you get out of the situation. 15 During a severe traumatic event, the activation of the fear response shuts down 80 to 90 percent of the brain’s function. 16 It’s very confusing and frightening when you cannot access your usual brain functioning. The next line of defense if you cannot flee to safety is the fight response, in which the anger circuits of your brain are activated. In this hyperaroused state, your heart rate, respiration, and blood pressure elevate. The hyperarousal induces a cascade of released stress hormones. Often a traumatic impact happens so quickly that, like Jonathan in his car accident, you’re unable to respond with any of these innate defenses, and they may remain stuck within you. If you cannot act on your instinctual mobilizing responses of fight or flight, and you cannot reach safety, your next resort is the freeze response. Your muscle tone is rigid; your eyes may dart around scanning for danger and escape routes, looking for possible lifesaving actions. However, if you cannot act, and the fear continues, your energy-saving parasympathetic nervous system (PNS) is triggered into action, creating a state of hypoarousal, or immobility, with lowered heart rate and blood pressure and slower respiration along with the release of pain-numbing endogenous opioids—should the threat be fatal, these make death more painless.

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  Minder Brain, The: How Your Brain Keeps You Alive, Protects You From Danger, And Ensures That You Reproduce

  How Your Brain Keeps You Alive, Protects You from Danger, and Ensures that You Reproduce

  • Joe Herbert(Author)
  • 2007(Publication Date)
  • World Scientific

    (Publisher)

  As you walk in the forest, you may come across a bear in the next clearing — a suitable moment for a flight response. But should it be an antelope, your reaction would be very different, and the sight of a weaker competitor might result in more fight than flight. A rustle in the undergrowth may also trigger a flight response, before you have time to know precisely what lies in wait. All this suggests that there must be room for some quite high level processing by the brain if the correct decision about how to respond behaviourally is to be made, even though the physical reaction of the sympathetic nervous system is undifferentiated. But is the emotion also undifferentiated? We might label the emotional response to an incipient (and perhaps unknown) threat as ‘anxiety’ or ‘arousal’ or even ‘fear’. The exact nature of the emotion itself might not matter; it serves only to elicit the emergency response, leaving the slower, more deliberate, ‘cognitive’ parts of the brain to work out exactly what has happened later. We consider the difficult subject of the emotions again in Chapter 12. If we accept this order of events, then the occurrence of stress (recognising the bear), triggers an emotional reaction, which in turn triggers the alterations in the body’s physiological reaction through the agency of the sympathetic nervous system. The initial adaptation is coded 66 The Minder Brain What is Stress? Adaptability is probably the most distinctive characteristic of life. . . none of the great forces of inanimate matter are as successful as that alertness and adaptability to change which we designate as life — and the loss of which is death. Indeed there is perhaps even a certain parallelism between the degree of aliveness and the extent of adaptability in every animal — in every man.

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  Mindful Somatic Awareness for Anxiety Relief

  • Blume, Michele L.(Authors)
  • 2020(Publication Date)
  • New Harbinger Publications

    (Publisher)

  When you know why a stimulus acts as a trigger for your anxiety, you can begin to under- stand and heal the unresolved fears it is linked to. With this infor- mation, you can also begin to challenge your perceptions. In this way you can see and experience the stimulus as nonthreatening, so that it no longer activates your fear. Anxiety and the Fear Response 63 The Basics of a Fear Response An effective fear response is dependent on the mind-body’s ability to detect and interpret sensory information from the external envi- ronment around you and the internal environment within you. So as you seek to understand your fear response, what you are seeking to understand is the unique way your sensory system detects and per- ceives information from the environment and how it integrates this information into behavioral, cognitive, and emotional responses intended to protect you from threat or danger (Porges 1993). Later in this chapter I will introduce three sensory feedback systems that help facilitate this process. For now, however, it is important to give you a basic understanding of the physiological, behavioral, and cog- nitive symptoms common to a fear response, so you can learn the unique way your mind-body responds to threat or danger. Physiological Symptoms of a Fear Response A fear response is instinctive and initiates a cascade of physiological processes that prepare the body to mobilize protective action, such as fight, flight, or freeze. These bodily processes include the release of stress hormones that facilitate swift and efficient use of energy to ensure the success of your protective efforts. Some of the changes experienced include accelerated heart rate and breathing, dilated pupils, and a decrease in digestive activity. Blood flow is pulled away from the extremities and toward the larger interior muscles and organs. This explains the cold and clammy hands and feet common to anxiety.

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  Coward

  Why We Get Anxious & What We Can Do About It

  • Tim Clare(Author)
  • 2022(Publication Date)
  • Canongate Books

    (Publisher)

  I’d tried to change my diet before. I’d met up with friends to do workouts. The new routine only ever lasted a few weeks before something got in the way. Feeling like I’d earned a break, I’d return to old vices with the frenzied abandon of a just-bathed spaniel rolling in fox shit. If I didn’t eat every couple of hours, I’d struggle to concentrate. My anxiety would spike. I’d stammer. My hands would become shaky. It became so bad my doctor sent me for a blood test to see if I was prediabetic. The test came back negative, but it was a wake-up call.

  I couldn’t go on with this cycle of peaks and crashes. But how was I supposed to magically attain the iron discipline to overhaul my diet and start exercising? I needed an expert. After a couple of emails, I headed to London to meet Dave Thomas, co-founder of the Foundry gym and a personal trainer with over 20,000 hours of training sessions under his belt.

  —

  ‘From a biochemical perspective, nothing has changed for our bodies from when we were hunter-gatherers.’ I met Dave at his gym in London, and we got talking about Cannon’s fight, flight or freeze response. Once, it helped us survive bears, wolves and sabre-toothed tigers – but we don’t have those any more. ‘What we do have is fucking annoying co-workers, we have stressful commutes, we have fast food, we have constant caffeine.’

  In the face of these psychological, physiological and dietary stressors, our bodies react as if we’re facing a physical threat. The stressful commute doesn’t even need to happen – just the anticipation that it might is enough to trigger the response. One working definition of ‘stress’ within medical and psychological literature is ‘a threat to homeostasis’.

  The main trigger within the body is the hypothalamus, a cone-shaped structure near the base of your brain.*

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  Origins of Phobias and Anxiety Disorders

  Why More Women than Men?

  • Michelle G. Craske(Author)
  • 2003(Publication Date)
  • Pergamon

    (Publisher)

  These response characteristics could be conceived as being consistent with the proposed function of worry~ to prepare and plan effectively for potential threat. Excessive autonomic arousal may impede complex cognitive processing; ongoing autonomic suppression commensurate with active verbal problem solving may represent the most adaptive response profile under conditions of potential threat. Fear: Responses and Function In contrast to worry about undetected but uncertain or potential threat conditions, fear is induced when threat is detected, at which time response systems shift to more active coping for self-preservation. Detection of threat implies some degree of certainty in comparison with the uncertain threat conditions that elicit worry. Hence, with detection, ~:utonomic activation becomes more prominent, as demonstrated in various studies of exposure to phobic stimuli (e.g., Kozak, Foa, & Steketee, 1988; see Chapter 7), and most clearly shown in studies of an approaching threat stimulus (whether conditioned or not) in unselected individuals. For example, Katkin and Hoffman (1976) observed an anticipatory rise in skin conductance over 10 minutes preceding the introduction of a spider. Similarly, individuals performing in public (whether reporting significant anxiety or not about the situation) demonstrate significant elevations in heart rate prior to performances (e.g., public speaking m Hofman, Newman, Ehlers, & Roth, 1995; musical performance m Craske & Craig, 1984), suggesting an arousal response to meet a challenge. Perhaps the strongest evidence derives from studies of autonomic arousal (e.g., Deane, 1969) and startle potentiation (e.g., Grillon, Ameli, Merikangas, Woods, & Davis, 1993; Grillon, Amelia, Woods, Merikangas, & Davis, 1991) in anticipation of shock.

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  Pain

  A Psychophysiological Analysis

  • Richard A. Sternbach(Author)
  • 2013(Publication Date)
  • Academic Press

    (Publisher)

  IV PHYSIOLOGICAL RESPONSES Any adequate stimulus, by definition, induces physiological re-sponses. If the stimulus is intense enough or of sufficient duration to be called painful, the pattern of physiological responses will be of a certain class which is now well known and which is generally referred to as activation. Before considering the responses which are unique to pain, it would be well to examine those which it shares with other activating stimuli. Activation T h e changes in ongoing processes which characterize activation are those which prepare the individual for great physical exertion. Cannon (1929) described the increase in heart rate and blood pres-sure, secretion of adrenaline, increase of circulating blood sugar and red blood cells, inhibition of gastric secretions and contrac-tions, decrease of blood supply to the viscera and superficial ves-sels, increased blood flow to the larger striated muscles, and dilata-tion of the bronchioles and of the pupils. These changes facilitate violent action: the large muscles are supplied with the necessary energy for rapid metabolism (oxygen and carbohydrates) and min-imal fatigue, and one of the effects of decreased superficial circula-tion and increased circulating adrenaline is to minimize the loss of blood in injury. These physiological responses have been called the fight or flight reaction, and are characteristic of anger and fear as well as 45 46 IV. PHYSIOLOGICAL RESPONSES pain. Manifestly they consist of greatly increased activity of the autonomic nervous system. In the average situation of a resting condition in which the individual displays slight fluctuations around his ideal or normal blood pressure, heart rate, etc., the two opposing branches of the autonomic, the sympathetic and par-asympathetic are in a state of dynamic equilibrium with respect to their innervation of the peripheral effectors.

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