Editing Fight-or-flight response

{{short description|Physiological reaction to a perceived threat or harmful event}}
{{Redirect|Fight or flight}}
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The '''fight-or-flight''' or the '''fight-flight-freeze-or-fawn'''<ref name="fawn">{{cite book |last=Walker |first=Peter |author-link= |date=2013 |title=Complex PTSD: From Surviving to Thriving : a Guide and Map for Recovering from Childhood Trauma |url= |location= |publisher= An Azure Coyote Book|page= |isbn=978-1-4928-7184-2}}</ref> (also called '''hyperarousal''' or the '''acute stress response''') is a physiological reaction that occurs in response to a perceived [[Psychological trauma|harmful event]], [[Trauma (medicine)|attack]], or threat to survival.<ref name="Cannon - Fight or Flight Response">{{cite book |last=Cannon |first=Walter |title=The Wisdom Of The Body |date=April 17, 1963 |publisher=W.W. Norton & Company |year=1963 |isbn=978-0393002058 |location=United States}}</ref> It was first described by [[Walter Bradford Cannon]] in 1915.{{efn| 1 =Cannon referred to "the necessities of fighting or flight." in the first edition of ''Bodily Changes in Pain, Hunger, Fear and Rage'' (1915), p.  211.  Some references say he first described the response in 1914 in ''[[The American Journal of Physiology]]''.}}<ref name="Walter Bradford Cannon 1915 211">{{Cite book|title=Bodily changes in pain, hunger, fear, and rage|author=[[Walter Bradford Cannon]]|publisher=[[Appleton-Century-Crofts]]|year=1915|location=New York|pages=211}}</ref> His theory states that animals react to threats with a general discharge of the [[sympathetic nervous system]], preparing the animal for fighting or fleeing.<ref name="Jansen - Intro fight or flight physiology">{{cite journal|last=Jansen|first=A|author2=Nguyen, X |author3=Karpitsky, V |author4= Mettenleiter, M |title=Central Command Neurons of the Sympathetic Nervous System: Basis of the Fight-or-Flight Response|journal=Science Magazine|date=27 October 1995|volume=5236|issue=270|pages=644–6|doi=10.1126/science.270.5236.644|pmid=7570024|bibcode=1995Sci...270..644J|s2cid=38807605}}</ref> More specifically, the [[adrenal medulla]] produces a hormonal cascade that results in the secretion of [[catecholamines]], especially [[norepinephrine]] and [[epinephrine]].<ref>{{cite book |author=Walter Bradford Cannon |title=Bodily Changes in Pain, Hunger, Fear and Rage: An Account of Recent Researches into the Function of Emotional Excitement |year=1915 |publisher=[[Appleton-Century-Crofts]] }}</ref> The hormones [[estrogen]], [[testosterone]], and [[cortisol]], as well as the neurotransmitters [[dopamine]] and [[serotonin]], also affect how organisms react to stress.<ref>{{cite news|title=Adrenaline, Cortisol, Norepinephrine: The Three Major Stress Hormones, Explained|url=http://www.huffingtonpost.com/2013/04/19/adrenaline-cortisol-stress-hormones_n_3112800.html|access-date=16 August 2014|work=Huffington Post|date=April 19, 2014}}</ref> The hormone [[osteocalcin]] might also play a part.<ref>{{Cite web|last=Kwon|first=Diana|title=Fight or Flight May Be in Our Bones|url=https://www.scientificamerican.com/article/fight-or-flight-may-be-in-our-bones/|access-date=2020-06-22|website=Scientific American|language=en}}</ref><ref>{{Cite web|title=Bone, not adrenaline, drives fight or flight response|url=https://phys.org/news/2019-09-bone-adrenaline-flight-response.html|access-date=2020-06-22|website=phys.org|language=en}}</ref>

This response is recognised as the first stage of the [[Stress (biology)#General adaptation syndrome|general adaptation syndrome]] that regulates [[Stress (biological)|stress]] responses among [[vertebrate]]s and other [[organism]]s.<ref name="Pathology - Theory Medical Student's Library">{{cite book|last=Gozhenko|first=A|title=PATHOLOGY – Theory. Medical Student's Library|year=2009|publisher=Radom|pages=270–275|author2=Gurkalova, I.P. |author3=Zukow, W |author4= Kwasnik, Z }}</ref>
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==Name==
Originally understood as the "fight-or-flight" response in Cannon's research,<ref name="Walter Bradford Cannon 1915 211"/> the state of hyperarousal results in several responses beyond fighting or fleeing. This has led people to calling it the "fight, flight, freeze" response, "fight-flight-freeze-fawn"<ref name="fawn" /><ref>{{Cite web |title=It’s Not Just ‘Fight or Flight’—Other Ways Your Body Responds To Stress |url=https://www.health.com/fight-flight-freeze-fawn-8348342 |access-date=2025-05-26 |website=Health |language=en}}</ref> or "fight-flight-faint-or-freeze", among other variants.<ref>{{cite book |last1=Donahue |first1=J.J. |chapter=Fight-Flight-Freeze System |editor1-last=Zeigler-Hill |editor1-first=V. |editor2-last=Shackelford |editor2-first=T.K. |title=Encyclopedia of Personality and Individual Differences |date=2020 |pages=1590–1595 |doi=10.1007/978-3-319-24612-3_751 |isbn=978-3-319-24610-9 |s2cid=240856695 }}</ref> 

The wider array of responses, such as [[Freezing behavior|freezing]], flop, faint, flee and fright,<ref>{{cite journal |last1=Bracha |first1=H. Stefan |title=Freeze, Flight, Fight, Fright, Faint: Adaptationist Perspectives on the Acute Stress Response Spectrum |journal=CNS Spectrums |date=September 2004 |volume=9 |issue=9 |pages=679–685 |doi=10.1017/S1092852900001954 |pmid=15337864 |s2cid=8430710 |url=http://cogprints.org/5014/1/2004_C.N.S_Five_Fs_of_FEAR--Freeze_Flight_Fight_Fright_Faint.pdf?q=fright |access-date=31 May 2021}}</ref> has led researchers to use more neutral or accommodating terminology such as "hyperarousal" or the "acute stress response".

==Physiology ==

===Autonomic nervous system===
{{See also|Autonomic nervous system}}
The autonomic nervous system is a control system that acts largely unconsciously and regulates [[heart rate]], [[digestion]], [[respiratory rate]], [[pupillary dilation|pupillary response]], [[Micturition|urination]], and [[sexual arousal]]. This system is the primary mechanism in control of the fight-or-flight response and its role is mediated by two different components: the sympathetic nervous system and the parasympathetic nervous system.<ref name="Human Physiology - Janig">{{cite book|editor-last=Janig|editor-first=W|title=Human Physiology|year=1989|publisher=Springer-Verlag|location=New York, NY|pages=333–370|author1=Schmidt, A |author2=Thews, G |edition=2|chapter=Autonomic Nervous System}}</ref>

[[File:The Autonomic Nervous System.jpg|thumb|455x455px|Comparison of Sympathetic and Parasympathetic nervous systems]]

====Sympathetic nervous system====
{{See also|Sympathetic nervous system}}
The sympathetic nervous system originates in the [[spinal cord]] and its main function is to activate the arousal responses that occur during the fight-or-flight response.<ref name=":2">{{Cite book |last1=Myers |first1=David G. |title=Psychology |last2=DeWall |first2=C. Nathan |publisher=MacMillan Publishing |year=2021 |edition=13 |pages=422}}</ref> The sympathetic nervous system transfers signals from the dorsal hypothalamus, which activates the heart, increases vascular resistance, and increases blood flow, especially to the muscle, heart, and brain tissues.<ref name=":02">{{Cite journal |last1=Kozlowska |first1=Kasia |last2=Walker |first2=Peter |last3=McLean |first3=Loyola |last4=Carrive |first4=Pascal |date=2015 |title=Fear and the Defense Cascade: Clinical Implications and Management |journal=[[Harvard Review of Psychiatry]] |volume=23 |issue=4 |pages=263–287 |doi=10.1097/HRP.0000000000000065 |issn=1067-3229 |pmc=4495877 |pmid=26062169}}</ref> It activates the adrenal medulla, releasing catecholamines that amplify the sympathetic response. Additionally, this component of the autonomic nervous system utilizes and activates the release of [[norepinephrine]] by the adrenal glands in the reaction.<ref name="Autonomic Nervous System - Chudler2">{{cite web |last=Chudler |first=Eric |title=Neuroscience For Kids |url=http://faculty.washington.edu/chudler/auto.html |access-date=19 April 2013 |publisher=University of Washington}}</ref>

====Parasympathetic nervous system====
{{See also|Parasympathetic nervous system}}
The parasympathetic nervous system originates in the sacral spinal cord and [[Medulla oblongata|medulla]], physically surrounding the sympathetic origin, and works in concert with the sympathetic nervous system. It is known as the calming portion of the autonomic nervous system.<ref name=":22">{{Cite book |last1=Myers |first1=David G. |title=Psychology |last2=DeWall |first2=C. Nathan |publisher=MacMillan Publishing |year=2021 |edition=13 |pages=422}}</ref> While the sympathetic nervous system is activated, the parasympathetic nervous system decreases its response. Efferent [[Vagus nerve|vagal fibers]] originating from the nucleus ambiguous fire in parallel to the respiratory system, decreasing the vagal cardiac parasympathetic tone.<ref name=":03">{{Cite journal |last1=Kozlowska |first1=Kasia |last2=Walker |first2=Peter |last3=McLean |first3=Loyola |last4=Carrive |first4=Pascal |date=2015 |title=Fear and the Defense Cascade: Clinical Implications and Management |journal=[[Harvard Review of Psychiatry]] |volume=23 |issue=4 |pages=263–287 |doi=10.1097/HRP.0000000000000065 |issn=1067-3229 |pmc=4495877 |pmid=26062169}}</ref> After the fight or flight response, the parasympathetic system's main function is to activate the "rest and digest" response and return the body to [[homeostasis]]. This system utilizes and activates the release of the neurotransmitter [[acetylcholine]].<ref name="Autonomic Nervous System - Chudler">{{cite web |last=Chudler |first=Eric |title=Neuroscience For Kids |url=http://faculty.washington.edu/chudler/auto.html |access-date=19 April 2013 |publisher=University of Washington}}</ref>

===Reaction===
The reaction begins in the [[amygdala]], which triggers a neural response in the [[hypothalamus]]. The initial reaction is followed by activation of the [[pituitary gland]] and secretion of the hormone [[Adrenocorticotropic hormone|ACTH]].<ref name="ACTH Action">{{cite web |last=Margioris |first=Andrew |title=ACTH Action on the Adrenal |url=http://www.endotext.org/adrenal/adrenal5/adrenal5.htm |publisher=Endotext.org |access-date=18 April 2013 |author2=Tsatsanis, Christos |date=April 2011 |url-status=dead |archive-url=https://web.archive.org/web/20130306182338/http://www.endotext.org/adrenal/adrenal5/adrenal5.htm |archive-date=6 March 2013 }}</ref> The [[adrenal gland]] is activated almost simultaneously, via the sympathetic nervous system, and releases the hormone [[epinephrine]]. The release of chemical messengers results in the production of the hormone [[cortisol]], which increases [[blood pressure]], [[blood sugar]], and suppresses the [[immune system]].<ref name="physiological reactions - Padgett & Glaser">{{cite journal|last=Padgett|first=David|author2=Glaser, R|title=How stress influences the immune response|journal=Trends in Immunology|date=August 2003|volume=24|issue=8|pages=444–448|doi=10.1016/S1471-4906(03)00173-X|pmid=12909458|citeseerx=10.1.1.467.1386}}</ref>

The initial response and subsequent reactions are triggered in an effort to create a boost of energy. This boost of energy is activated by epinephrine binding to [[cells (biology)|liver cells]] and the subsequent production of [[glucose]].<ref name="Glycogen Metabolism - King">{{cite web |last=King |first=Michael |title=PATHWAYS: GLYCOGEN & GLUCOSE |url=http://neuromuscular.wustl.edu/pathol/diagrams/glycogen.htm |publisher=[[Washington University in St. Louis]]}}</ref> Additionally, the circulation of cortisol functions to turn [[fatty acids]] into available energy, which prepares muscles throughout the body for response.<ref name="Cell Communication in Fight or Flight">{{cite web |title=HOW CELLS COMMUNICATE DURING THE FIGHT OR FLIGHT RESPONSE |url=http://learn.genetics.utah.edu/content/begin/cells/fight_flight/ |publisher=University of Utah |access-date=18 April 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130808004906/http://learn.genetics.utah.edu/content/begin/cells/fight_flight/ |archive-date=8 August 2013 }}</ref>

Catecholamine hormones, such as [[Epinephrine|adrenaline]] ([[epinephrine]]) or [[noradrenaline]] (norepinephrine), facilitate immediate physical reactions associated with a preparation for violent [[muscular]] action.<ref name=gleitman>{{Cite book|author= [[Henry Gleitman]], Alan J. Fridlund and [[Daniel Reisberg]] |title= Psychology |edition= 6 |year= 2004 |publisher= [[W. W. Norton & Company]] |isbn= 978-0-393-97767-7 }}</ref>

===Function of physiological changes===
The physiological changes that occur during the fight or flight response are activated to give the body increased strength and speed in anticipation of fighting or running. Some of the specific physiological changes and their functions include:<ref name="Physiological Changes - Tripod2">{{cite web |last=Stress Management for Health Course |title=The Fight Flight Response |url=http://stresscourse.tripod.com/id11.html |access-date=19 April 2013}}</ref><ref name="The Science of Stress - Olpin2">{{cite web |last=Olpin |first=Michael |title=The Science of Stress |url=http://faculty.weber.edu/molpin/healthclasses/1110/bookchapters/stressphysiologychapter.htm |url-status=dead |archive-url=https://web.archive.org/web/20171120215838/http://faculty.weber.edu/molpin/healthclasses/1110/bookchapters/stressphysiologychapter.htm |archive-date=2017-11-20 |access-date=2013-04-25 |publisher=Weber State University}}</ref><ref name=":23">{{Cite book |last1=Myers |first1=David G. |title=Psychology |last2=DeWall |first2=C. Nathan |publisher=MacMillan Publishing |year=2021 |edition=13 |pages=422}}</ref>

* Increased [[blood flow]] to the muscles activated by diverting blood flow from other parts of the body to make taking quick action easier.
* Increased blood pressure and heart rate enhance cardiac output in order to supply the body with more energy.
* The [[liver]] secretes increased amounts of [[glucose]] (through adrenaline-induced [[glycogenolysis]])<ref>{{Cite web |title=Glycogenolysis {{!}} Glucose Metabolism, Liver Function & Regulation {{!}} Britannica |url=https://www.britannica.com/science/glycogenolysis |access-date=2025-01-09 |website=www.britannica.com |language=en}}</ref> and fats into the blood to provide the body with a fuel source to meet energy demands.
* The [[respiratory rate]] increases to supply the oxygen necessary to help burn the extra glucose.
* The [[Coagulation|blood clotting]] function of the body speeds up in order to reduce [[bleeding]] and prevent excessive blood loss in the event of an injury sustained during the response.
* Increased [[Muscle tone|muscle tension]] in order to provide the body with extra speed and strength, which can result in trembling or shaking until the tension is released.
* The pupils [[Mydriasis|dilate]] to let in more light, allowing for better vision of the body's surroundings.

==Emotional components==

===Emotion regulation===
{{See also|Emotional self-regulation}}
In the context of the fight or flight response, emotional regulation is used proactively to avoid threats of stress or to control the level of emotional arousal. Emotional socialization can develop someone's ability to successfully regulate their emotions. Faced with a perceived threat (in the context of a fight or flight situation) those raised with supportive parental behaviors are far more likely to easily self-regulate their emotions.<ref name="Emotional Regulation - Cistler">{{cite journal|last=Cistler|first=Josh|author2=Bunmi O. Olatunji |author3=Matthew T. Feldner |author4=John P. Forsyth |title=Emotion Regulation and the Anxiety Disorders: An Integrative Review|journal=Journal of Psychopathology and Behavioral Assessment|year=2010|volume=32|issue=1|pages=68–82|doi=10.1007/s10862-009-9161-1|pmid=20622981|pmc=2901125}}</ref><ref name="Emotional Regulation - Gross">{{cite journal|last=Gross|first=James|title=Sharpening the Focus: Emotion Regulation, Arousal, and Social Competence|journal=Psychological Inquiry|year=1998|volume=9|issue=4|pages=287–290|doi=10.1207/s15327965pli0904_8}}</ref>

===Emotional reactivity===
During the reaction, the intensity of emotion that is brought on by the stimulus will also determine the nature and intensity of the behavioral response.<ref name="Emotional Reactivity - Avero">{{cite journal|last=Avero|first=Pedro|author2=Calvo, M|title=Emotional reactivity to social-evaluative stress: genderdifferences in response systems concordance|journal=Personality and Individual Differences|date=1 July 1999|volume=27|issue=1|pages=155–170|doi=10.1016/S0191-8869(98)00229-3}}</ref> In a experiment conducted by Clayton, Lang, Leshner and Quick (2019), they viewed the responses of 49 participants to antitobacco messages.<ref>{{Cite journal |last1=Clayton |first1=Russell B. |last2=Lang |first2=Annie |last3=Leshner |first3=Glenn |last4=Quick |first4=Brian L. |date=2019-07-04 |title=Who Fights, Who Flees? An Integration of the LC4MP and Psychological Reactance Theory |url=https://www.tandfonline.com/doi/full/10.1080/15213269.2018.1476157 |journal=Media Psychology |language=en |volume=22 |issue=4 |pages=545–571 |doi=10.1080/15213269.2018.1476157 |issn=1521-3269|url-access=subscription }}</ref> Participants reacted in two orders of fashion after seeing the message with the individual smoker and their effects on those surrounding them.<ref>{{Cite journal |last1=Sanders-Jackson |first1=Ashley N. |last2=Cappella |first2=Joseph N. |last3=Linebarger |first3=Deborah L. |last4=Piotrowski |first4=Jessica Taylor |last5=O'Keeffe |first5=Moira |last6=Strasser |first6=Andrew A. |date=2011-04-01 |title=Visual Attention to Antismoking PSAs: Smoking Cues versus Other Attention-Grabbing Features |journal=Human Communication Research |volume=37 |issue=2 |pages=275–292 |doi=10.1111/j.1468-2958.2010.01402.x |issn=0360-3989 |pmc=3489183 |pmid=23136462}}</ref> The first reaction was participants who had higher defense mechanisms, who decided to ignore the messages, while the other participants who had lower defense mechanisms, ended up arguing and becoming frustrated after viewing the antitobacco messages.<ref>{{Cite journal |last1=Clayton |first1=Russell B. |last2=Leshner |first2=Glenn |last3=Tomko |first3=Rachel L. |last4=Trull |first4=Timothy J. |last5=Piasecki |first5=Thomas M. |date=2017-03-04 |title=Who Fights, Who Flees? An Integration of the LC4MP and Psychological Reactance Theory |journal=Media Psychology |volume=22 |issue=3 |pages=254–261 |doi=10.1080/10810730.2016.1268222 |issn=1081-0730 |pmc=5451094 |pmid=28248620}}</ref><ref>{{Cite journal |last1=Wong |first1=Norman C. H. |last2=Harrison |first2=Kylie J. |last3=Harvell |first3=Lindsey A. |date=2015-09-24 |title=Reactance and Public Health Messages: The Unintended Dangers of Anti-tobacco PSAs |url=http://redfame.com/journal/index.php/smc/article/view/1022 |journal=Studies in Media and Communication |language=en |volume=3 |issue=2 |pages=72–83 |doi=10.11114/smc.v3i2.1022 |issn=2325-808X}}</ref> Individuals with higher levels of emotional reactivity (Such as an [[anxiety disorder]]) may be prone to [[anxiety]] and [[aggression]], which illustrates the implications of appropriate emotional reaction in the fight or flight response.<ref name="Emotional Reactivity - Carthy">{{cite journal|last=Carthy|first=T|author2=Horesh N |author3=Apter A |author4=Edge MD |author5=Gross JJ |title=Emotional reactivity and cognitive regulation in anxious children|journal=Behaviour Research and Therapy|date=May 2010|volume=48|issue=5|pages=384–393|doi=10.1016/j.brat.2009.12.013|pmid=20089246|s2cid=14382059}}</ref><ref name="Emotional reactivity - Valiente">{{cite journal|last=Valiente|first=C|author2=Eisenberg N |author3=Smith CL |author4=Reiser M |author5=Fabes RA |author6=Losoya S |author7=Guthrie IK |author8=Murphy BC |title=The relations of effortful control and reactive control to children's externalising problems: A longitudinal assessment|journal=Personality|date=December 2003|volume=71|issue=6|pages=1171–1196|doi=10.1111/1467-6494.7106011 |pmid=14633062}}</ref>

==Cognitive components==

===Content specificity===
The specific components of cognitions in the fight or flight response seem to be largely negative. These negative cognitions may be characterised by: attention to negative stimuli, the perception of ambiguous situations as negative, and the recurrence of recalling negative words.<ref name="Content specificity - Reid">{{cite journal|last1=Reid|first1=Sophie C.|last2=Salmon|first2=Karen|author3=Peter F. Lovibond|title=Cognitive Biases in Childhood Anxiety, Depression, and Aggression: Are They Pervasive or Specific?|journal=Cognitive Therapy and Research|date=October 2006|volume=30|issue=5|pages=531–549|doi=10.1007/s10608-006-9077-y|s2cid=28911747}}</ref> There also may be specific negative thoughts associated with emotions commonly seen in the reaction.<ref name="Content Specificity - Beck">{{cite book|last=Beck|first=Aaron|title=Cognitive Therapy and the Emotional Disorders|year=1979|publisher=Penguin Books|location=United States}}</ref>

===Perception of control===
{{See also|Control (psychology)}}
[[Perceived control]] relates to an individual's thoughts about control over situations and events.<ref name="Perceived Control - Weems">{{cite journal|last=Weems|first=CF|author2=Silverman, WK|title=An integrative model of control: implications for understanding emotion regulation and dysregulation in childhood anxiety|journal=Journal of Affective Disorders|date=April 2006|volume=91|issue=2|pages=113–124|doi=10.1016/j.jad.2006.01.009|pmid=16487599}}</ref> Perceived control should be differentiated from actual control because an individual's beliefs about their abilities may not reflect their actual abilities. Therefore, overestimation or underestimation of perceived control can lead to anxiety and aggression.<ref name="Perceived Control - Brendgen">{{cite journal|last=Brendgen|first=M|author2=Vitaro F |author3=Turgeon L |author4=Poulin F |author5=Wanner B |title=Is there a dark side of positive illusions? Overestimation of social competence and subsequent adjustment in aggressive and nonaggressive children|journal=Journal of Abnormal Child Psychology|date=June 2004|volume=32|issue=3|pages=305–320|doi=10.1023/B:JACP.0000026144.08470.cd|pmid=15228179|s2cid=11239252}}</ref>

===Social information processing===
{{See also|Social information processing (cognition)}}
The social information processing model proposes a variety of factors that determine behavior in the context of social situations and preexisting thoughts.<ref name="Social Information Processing - Crick">{{cite journal|last=Crick|first=Nicki|author2=Dodge, Kenneth|title=A review and reformulation of social information-processing mechanisms in children's social adjustment|journal=Psychological Bulletin|date=January 1994|volume=115|issue=1|pages=74–101|doi=10.1037/0033-2909.115.1.74}}</ref> The attribution of hostility, especially in ambiguous situations, seems to be one of the most important cognitive factors associated with the fight or flight response because of its implications towards aggression.<ref name="Social Information Processing - Dodge">{{cite journal|last=Dodge|first=Kenneth|title=Social cognition and children's aggressive behavior|journal=Journal of Child Development|date=March 1980|volume=51|issue=1|pages=162–170|doi=10.2307/1129603|jstor=1129603|pmid=7363732 }}</ref>

==Other animals==

===Evolutionary perspective===
An [[evolutionary psychology]] explanation is that early animals had to react to threatening stimuli quickly and did not have time to psychologically and physically prepare themselves.<ref name=":1">{{Cite journal |last=Adamo |first=S. A. |date=2014-09-01 |title=The Effects of Stress Hormones on Immune Function May be Vital for the Adaptive Reconfiguration of the Immune System During Fight-or-Flight Behavior |journal=Integrative and Comparative Biology |language=en |volume=54 |issue=3 |pages=419–426 |doi=10.1093/icb/icu005 |issn=1540-7063|doi-access=free |pmid=24691569 }}</ref> The fight or flight response provided them with the mechanisms to rapidly respond to threats against survival.<ref name="Purpose of fight or fight - Grohol">{{cite web|last=Grohol|first=John|title=What's the purpose of the fight or flight response?|url=http://psychcentral.com/blog/archives/2012/12/04/whats-the-purpose-of-the-fight-or-flight-response/|access-date=18 April 2013|archive-date=23 March 2013|archive-url=https://web.archive.org/web/20130323170934/http://psychcentral.com/blog/archives/2012/12/04/whats-the-purpose-of-the-fight-or-flight-response/|url-status=dead}}</ref><ref name="Concepts of Stress - Goldstein">{{cite journal|last=Goldstein|first=David|author2=Kopin, I|title=Evolution of concepts of stress|journal=Stress|year=2007|volume=10|issue=2|doi=10.1080/10253890701288935|pages=109–20|pmid=17514579|s2cid=25072963|doi-access=free}}</ref>

===Examples===
A typical example of the stress response is a grazing [[zebra]]. If the zebra sees a [[lion]] closing in for the kill, the stress response is activated as a means to escape its [[Predatory imminence continuum|predator]]. The escape requires intense muscular effort, supported by all of the body's systems. The [[sympathetic nervous system]]'s activation  provides for these needs. A similar example involving fight is of a cat about to be attacked by a dog. The cat shows accelerated heartbeat, [[piloerection]] (hair standing on end), and pupil dilation, all signs of sympathetic arousal.<ref name=gleitman/> Note that the zebra and cat still maintain [[homeostasis]] in all states.

In July 1992, ''[[Behavioral Ecology (journal)|Behavioral Ecology]]'' published experimental research conducted by biologist Lee A. Dugatkin where [[Guppy|guppies]] were sorted into "bold", "ordinary", and "timid" groups based upon their reactions when confronted by a [[smallmouth bass]] (i.e. inspecting the predator, hiding, or swimming away) after which the guppies were left in a tank with the bass. After 60 hours, 40 percent of the timid guppies and 15 percent of the ordinary guppies survived while none of the bold guppies did.<ref>{{cite journal|last=Dugatkin|first=Lee Alan|title=Tendency to inspect predators predicts mortality risk in the guppy ''(Poecilia reticulata)''|journal=[[Behavioral Ecology (journal)|Behavioral Ecology]]|year=1992|publisher=[[Oxford University Press]]|volume=3|issue=2|pages=125–127|doi=10.1093/beheco/3.2.124|url=https://academic.oup.com/beheco/article-abstract/3/2/124/218010|access-date=September 9, 2020|url-access=subscription}}</ref><ref>{{cite book|last1=Nesse|first1=Randolph|author-link1=Randolph M. Nesse|last2=Williams|first2=George C.|author-link2=George Christopher Williams|title=Why We Get Sick: The New Science of Darwinian Medicine|year=1994|page=213|publisher=[[Vintage Books]]|place=New York|isbn=978-0-679-74674-4}}</ref>

===Varieties of responses===
{{more citations needed|date=October 2016|section}}
[[File:Ruseckas-Stumbro medžioklė.jpg|thumb|Bison hunted by dogs]]
Animals respond to threats in many complex ways.<ref name=":0" /> Rats, for instance, try to escape when threatened but will fight when cornered. Some animals stand perfectly still so that predators will not see them.<ref>{{Cite news |last=Schulz |first=Kathryn |date=2024-10-28 |title=What Do Animals Understand About Death? |url=https://www.newyorker.com/magazine/2024/11/04/playing-possum-susana-monso-book-review |access-date=2025-05-26 |work=The New Yorker |language=en-US |issn=0028-792X}}</ref> Many animals freeze or play dead when touched in the hope that the predator will lose interest.<ref>{{Cite journal |last1=Niermann |first1=H.C.M. |last2=Figner |first2=F. |last3=Roelofs |first3=K. |date=January 24, 2017 |title=Individual differences in defensive stress-responses: the potential relevance for psychopathology |url=https://www.sciencedirect.com/science/article/pii/S2352154616301425 |journal=Current Opinion in Behavioral Sciences |volume=14 |pages=94–101 |doi=10.1016/j.cobeha.2017.01.002 |via=Science Direct|hdl=2066/166278 |hdl-access=free }}</ref><ref>{{Cite web |last=Bristol |first=University of |title=How long to play dead in order to stay alive? |url=https://www.bristol.ac.uk/news/2020/july/antlions-play-dead.html |access-date=2025-05-26 |website=www.bristol.ac.uk |language=en-GB}}</ref><ref>{{Cite journal |last=Humphreys |first=Rosalind K. |last2=Ruxton |first2=Graeme D. |date=2018 |title=A review of thanatosis (death feigning) as an anti-predator behaviour |url=https://pmc.ncbi.nlm.nih.gov/articles/PMC5769822/ |journal=Behavioral Ecology and Sociobiology |volume=72 |issue=2 |pages=22 |doi=10.1007/s00265-017-2436-8 |issn=0340-5443 |pmc=5769822 |pmid=29386702}}</ref>

Other animals have alternative self-protection methods. Some species of [[Ectotherm|cold-blooded]] animals [[Chromatophore|change color]] swiftly to camouflage themselves.<ref name="Fish changing colors">{{cite book|last=Gill|first=A.C.|title=Revision of the Indo-Pacific dottyback fish subfamily Pseudochrominae (Perciformes: Pseudochromidae)|year=2004|publisher=Smithiana Monographs|pages=1–123}}</ref> These responses are triggered by the [[sympathetic nervous system]], but, in order to fit the model of fight or flight, the idea of flight must be broadened to include escaping capture either in a physical or sensory way.<ref>{{Cite journal |last=Rösler |first=Lara |last2=Gamer |first2=Matthias |date=2019-11-20 |title=Freezing of gaze during action preparation under threat imminence |url=https://www.nature.com/articles/s41598-019-53683-4 |journal=Scientific Reports |language=en |volume=9 |issue=1 |pages=17215 |doi=10.1038/s41598-019-53683-4 |issn=2045-2322}}</ref><ref>{{Cite journal |last=Kozlowska |first=Kasia |last2=Walker |first2=Peter |last3=McLean |first3=Loyola |last4=Carrive |first4=Pascal |date=2015 |title=Fear and the Defense Cascade: Clinical Implications and Management |url=https://pmc.ncbi.nlm.nih.gov/articles/PMC4495877/ |journal=Harvard Review of Psychiatry |volume=23 |issue=4 |pages=263–287 |doi=10.1097/HRP.0000000000000065 |issn=1465-7309 |pmc=4495877 |pmid=26062169}}</ref> Thus, flight can be disappearing to another location or just disappearing in place, and fight and flight are often combined in a given situation.<ref name="BIFF Response-Aballay">{{cite journal|last=Singh|first=J|author2=Aballay, A|title=Microbial Colonization Activates an Immune Fight-and-Flight Response via Neuroendocrine Signaling|journal=Developmental Cell|date=April 8, 2019|volume=49|issue=1|pages=89–99|doi=10.1016/j.devcel.2019.02.001|pmid=30827896|pmc=6456415|doi-access=free}}</ref>

The fight or flight actions also have polarity – the individual can either fight against or flee from something that is threatening, such as a hungry lion, or fight for or fly towards something that is needed, such as the safety of the shore from a raging river.<ref name=":0">{{Cite web |date=2023-11-09 |title=Fight, Flight, Freeze, or Fawn: How We Respond to Threats |url=https://www.simplypsychology.org/fight-flight-freeze-fawn.html |access-date=2025-05-26 |language=en-US}}</ref>

A threat from another animal does not always result in immediate fight or flight. There may be a period of heightened awareness, during which each animal interprets behavioral signals from the other. Signs such as paling, piloerection, immobility, sounds, and body language communicate the status and intentions of each animal. There may be a sort of negotiation, after which fight or flight may ensue, but which might also result in playing, mating, or nothing at all. An example of this is kittens playing: each kitten shows the signs of sympathetic arousal, but they never inflict real damage.<ref>{{Cite journal |last=Roelofs |first=Karin |date=2017-04-19 |title=Freeze for action: neurobiological mechanisms in animal and human freezing |url=https://pmc.ncbi.nlm.nih.gov/articles/PMC5332864/ |journal=Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences |volume=372 |issue=1718 |pages=20160206 |doi=10.1098/rstb.2016.0206 |issn=1471-2970 |pmc=5332864 |pmid=28242739}}</ref><ref>{{Cite web |title=The 5 Fs: fight, flight, freeze, flop and friend |url=https://rapecrisis.org.uk/get-help/tools-for-victims-and-survivors/understanding-your-response/fight-or-flight/ |access-date=2025-05-26 |website=Rape Crisis England & Wales}}</ref>

==In criminal law==
Acute stress response is a common issue in self-defense criminal cases. Expert opinions are usually required if the defender's fault becomes the focus of the case.<ref>{{cite book
	| last = Gawron
	| first = Tomáš
	| author-link = 
	| date = 2023
	| title = Nutná obrana v právní praxi
	| url = https://knihovna.usoud.cz/arl-us/cs/detail-us_us_cat-0054718-Nutna-obrana-v-pravni-praxi/?disprec=1&iset=1
	| location = Brno
	| publisher = Václav Klemm
	| page = 289
	| isbn = 978-80-87713-23-5
    | lang = cs
}}</ref>

==See also==
{{columns-list|colwidth=22em|
* [[Acute stress reaction]]
* [[Anxiety]]
* [[Anxiety disorder]]
* [[Apparent death]]
* [[Body reactivity]]
* [[Coping (psychology)]]
* [[Defense physiology]]
* [[Domestication of the dog]]
* [[Emotional dysregulation]]
* [[Fear]]
* [[Freezing behavior]]
* [[Generalized anxiety disorder]]
* [[Escape distance]]
* [[Hypothalamic–pituitary–adrenal axis]]
* [[Panic attack]]
* [[Phobia]]
* [[Rest and digest]]
* [[Social anxiety]]
* [[Social anxiety disorder]]
* [[Tend and befriend]]
* ''[[The Relaxation Response]]''
* [[Vasoconstriction]]
* [[Yerkes–Dodson law]]
* [[Reflex syncope]]
* [[Hypervigilance]]}}

==Notes==
{{notelist}}

==References==
{{Reflist}}

==Further reading==
* [[Robert Sapolsky|Sapolsky, Robert M.]], 1994.  Why Zebras Don't Get Ulcers.  W.H. Freeman and Company.
* {{USGovernment|url=http://www.surgeongeneral.gov/library/mentalhealth/chapter4/sec2_1.html}}
* Arun, C. P. (2004). Fight or flight, forbearance and fortitude: the spectrum of actions of the catecholamines and their cousins. ''Annals of the New York Academy of sciences'', ''1018''(1), 137-140. 
* Seng, J., & Group, C. (2019). From Fight or Flight, Freeze or Faint, to “Flow”: Identifying a Concept to Express a Positive Embodied Outcome of Trauma Recovery. ''Journal of the American Psychiatric Nurses Association'', ''25''(3), 200-207.
* Katz, Carmit., Tsur, Noga., Talmon, Anat., and Nicolet, Racheli, (2021). Beyond fight, flight,     and freeze: Towards a new conceptualization of peritraumatic responses to child sexual abuse based on retrospective accounts of adult survivors. ''Child Abuse and Neglect, 112''(1), 1-12
* O’Dea, Connor., Castro Bueno, Angelica M., and Saucier, Donald A, (2017). Fight or flight: Perceptions of men who confront versus ignore threats to themselves and others. ''Personality and Individual Differences, 104''(1), 345-351. 

==External links==
*{{commons category-inline}}

{{Evolutionary psychology}}

{{DEFAULTSORT:Fight-Or-Flight Response}}
[[Category:Sympathetic nervous system]]
[[Category:Aggression]]
[[Category:Fear]]
[[Category:Psychological theories]]
[[Category:Evolutionary psychology]]