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{{Short description|State of low mood and aversion to activity}}
{{Redirect|Hopelessness|the album|Hopelessness (album){{!}}''Hopelessness'' (album)}}
{{Redirect|Despair}}
{{pp-semi-indef|small=yes}}
{{Use dmy dates|date=April 2024}}
{{Infobox medical condition (new)
| name          = Depression
| image         = A man diagnosed as suffering from melancholia with strong su Wellcome L0026693.jpg
| caption       = [[Lithograph]] of a person diagnosed with [[melancholia]] and strong suicidal tendency in 1892
| alt           = 
| field         = [[Psychiatry]], [[psychology]]
| symptoms      = Low mood, aversion to activity, loss of interest, loss of feeling pleasure
| complications = 
| onset         = 
| duration      = 
| causes        = Brain chemistry, genetics, life events, medical conditions, personality<ref name="clevelandclinic">{{cite web |publisher=Cleveland Clinic |title=Depression|date=2022 |url=https://my.clevelandclinic.org/health/diseases/9290-depression|access-date=9 June 2022}}</ref>
| risks         = Stigma of mental health disorder<ref name="shrivastavaA">{{cite journal | vauthors = Shrivastava A, Bureau Y, Rewari N, Johnston M | title = Clinical risk of stigma and discrimination of mental illnesses: Need for objective assessment and quantification | journal = Indian Journal of Psychiatry | volume = 55 | issue = 2 | pages = 178–82 | date = April 2013 | pmid = 23825855 | pmc = 3696244 | doi = 10.4103/0019-5545.111459 | doi-access = free }}</ref>
| diagnosis     = [[Patient Health Questionnaire]], [[Beck Depression Inventory]]
| differential  = [[Anxiety]], [[bipolar disorder]], [[borderline personality disorder]]
| prevention    = Social connections, physical activity
| treatment     = [[Psychotherapy]], [[psychopharmacology]]
| medication    = 
| prognosis     = 
| frequency     = 
| deaths        = 
}}
{{emotion}}

'''Depression''' is a [[mental state]] of low [[Mood (psychology)|mood]] and aversion to activity.<ref>{{Cite web|date=2016 |title=NIMH » Depression Basics |url=https://www.nimh.nih.gov/health/publications/depression/index.shtml|access-date=22 October 2020 |website=www.nimh.nih.gov|archive-date=11 June 2013|archive-url=https://web.archive.org/web/20130611091923/http://www.nimh.nih.gov/health/publications/depression/complete-index.shtml|url-status=live}}</ref> It affects more than 280 million people of all ages (about 3.5% of the global population).<ref name=":3">{{Cite web |title=Depression |url=https://www.who.int/news-room/fact-sheets/detail/depression |url-status=live |archive-url=https://web.archive.org/web/20201226072232/https://www.who.int/news-room/fact-sheets/detail/depression |archive-date=26 December 2020 |access-date=7 April 2021 |website=www.who.int |language=en}}</ref> Depression affects a person's thoughts, behavior, feelings, and [[subjective well-being|sense of well-being]].<ref>{{cite journal | vauthors = de Zwart PL, Jeronimus BF, de Jonge P | title = Empirical evidence for definitions of episode, remission, recovery, relapse and recurrence in depression: a systematic review | journal = Epidemiology and Psychiatric Sciences | volume = 28 | issue = 5 | pages = 544–562 | date = October 2019 | pmid = 29769159 | pmc = 7032752 | doi = 10.1017/S2045796018000227 | doi-access = free }}</ref> Depressed people often experience loss of motivation or interest in, or reduced pleasure or joy from, experiences that would normally bring them pleasure or joy.<ref name=":1">{{Cite book|title=Psychotherapy and counselling for depression| vauthors = Gilbert P |date=2007|publisher=Sage|isbn=978-1-84920-349-4|edition=3rd|location=Los Angeles|oclc=436076587}}{{page needed|date=November 2023}}</ref> 

Depressed mood is a symptom of some [[mood disorders]] such as [[major depressive disorder]] and [[dysthymia]];<ref>
{{cite book |title=Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) |author=American Psychiatric Association |year=2013 |publisher=American Psychiatric Association}}{{page needed|date=July 2023}}
</ref> it is a normal temporary reaction to life events, such as the loss of a loved one; and it is also a symptom of some physical diseases and a side effect of some drugs and medical treatments.
It may feature sadness, difficulty in thinking and concentration and a significant increase or decrease in appetite and time spent sleeping. People experiencing depression may have feelings of dejection or hopelessness and may experience suicidal thoughts. It can either be short term or long term.

== Contributing factors ==
[[File:Allegory on Melancholy Met DP885774.jpg|thumb|Allegory on melancholy, from {{circa|1729}}–1740, etching and engraving, in the [[Metropolitan Museum of Art]] (New York City)]]

=== Life events ===
[[Adverse childhood experiences|Adversity in childhood]], such as bereavement, neglect, mental abuse, physical abuse, sexual abuse, or unequal parental treatment of siblings can contribute to depression in adulthood.<ref>{{cite journal | vauthors = Heim C, Newport DJ, Mletzko T, Miller AH, Nemeroff CB | title = The link between childhood trauma and depression: insights from HPA axis studies in humans | journal = Psychoneuroendocrinology | volume = 33 | issue = 6 | pages = 693–710 | date = July 2008 | pmid = 18602762 | doi = 10.1016/j.psyneuen.2008.03.008 | s2cid = 2629673 }}</ref><ref>{{cite journal | vauthors = Pillemer K, Suitor JJ, Pardo S, Henderson C | title = Mothers' Differentiation and Depressive Symptoms among Adult Children | journal = Journal of Marriage and the Family | volume = 72 | issue = 2 | pages = 333–345 | date = April 2010 | pmid = 20607119 | pmc = 2894713 | doi = 10.1111/j.1741-3737.2010.00703.x }}</ref> Childhood physical or sexual abuse in particular significantly correlates with the likelihood of experiencing depression over the survivor's lifetime.<ref>{{cite journal | vauthors = Lindert J, von Ehrenstein OS, Grashow R, Gal G, Braehler E, Weisskopf MG | title = Sexual and physical abuse in childhood is associated with depression and anxiety over the life course: systematic review and meta-analysis | journal = International Journal of Public Health | volume = 59 | issue = 2 | pages = 359–72 | date = April 2014 | pmid = 24122075 | doi = 10.1007/s00038-013-0519-5 | s2cid = 24138761 }}</ref> People who have experienced four or more [[adverse childhood experiences]] are 3.2 to 4.0 times more likely to suffer from depression.<ref name="Anda2006">{{cite journal |display-authors=6 |vauthors=Anda RF, Felitti VJ, Bremner JD, Walker JD, Whitfield C, Perry BD, Dube SR, Giles WH |date=April 2006 |title=The enduring effects of abuse and related adverse experiences in childhood. A convergence of evidence from neurobiology and epidemiology |journal=European Archives of Psychiatry and Clinical Neuroscience |volume=256 |issue=3 |pages=174–186 |doi=10.1007/s00406-005-0624-4 |pmc=3232061 |pmid=16311898}}</ref> Poor housing quality, non-functionality, lack of green spaces, and exposure to noise and air pollution are linked to depressive moods, emphasizing the need for consideration in planning to prevent such outcomes.<ref>{{Cite journal |last1=Rautio |first1=Nina |last2=Filatova |first2=Svetlana |last3=Lehtiniemi |first3=Heli |last4=Miettunen |first4=Jouko |date=February 2018 |title=Living environment and its relationship to depressive mood: A systematic review |journal=International Journal of Social Psychiatry |language=en |volume=64 |issue=1 |pages=92–103 |doi=10.1177/0020764017744582 |issn=0020-7640|doi-access=free |pmid=29212385 }}</ref>

Studies have consistently shown that physicians have had the highest depression and suicide rates compared to people in many other lines of work—for suicide, 40% higher for male physicians and 130% higher for female physicians.<ref>{{Cite journal |last1=Rotenstein |first1=Lisa S. |last2=Ramos |first2=Marco A. |last3=Torre |first3=Matthew |last4=Segal |first4=J. Bradley |last5=Peluso |first5=Michael J. |last6=Guille |first6=Constance |last7=Sen |first7=Srijan |last8=Mata |first8=Douglas A. |date=6 December 2016 |title=Prevalence of Depression, Depressive Symptoms, and Suicidal Ideation Among Medical Students: A Systematic Review and Meta-Analysis |journal=JAMA |volume=316 |issue=21 |pages=2214–2236 |doi=10.1001/jama.2016.17324 |pmc=5613659 |pmid=27923088}}</ref><ref>{{cite journal |last1=Mata |first1=Douglas A. |last2=Ramos |first2=Marco A. |last3=Bansal |first3=Narinder |last4=Khan |first4=Rida |last5=Guille |first5=Constance |last6=Di Angelantonio |first6=Emanuele |last7=Sen |first7=Srijan |date=8 December 2015 |title=Prevalence of Depression and Depressive Symptoms Among Resident Physicians |journal=JAMA |volume=314 |issue=22 |pages=2373–83 |doi=10.1001/jama.2015.15845 |pmc=4866499 |pmid=26647259}}</ref><ref name="nytimes2">{{cite news |last1=Chen |first1=Pauline W. |date=7 October 2010 |title=Medical Student Distress and the Risk of Doctor Suicide |newspaper=The New York Times |url=https://www.nytimes.com/2010/10/07/health/views/07chen.html |access-date=9 February 2015}}</ref>

Life events and changes that may cause depressed mood include (but are not limited to): childbirth, menopause, financial difficulties, unemployment, stress (such as from work, education, military service, family, living conditions, marriage, etc.), a medical diagnosis (cancer, HIV, diabetes, etc.), bullying, loss of a loved one, natural disasters, social isolation, rape, relationship troubles, jealousy, separation, drug abuse, alcohol abuse, or [[catastrophic injury]].<ref>{{cite journal | vauthors = Schmidt PJ | title = Mood, depression, and reproductive hormones in the menopausal transition | journal = The American Journal of Medicine | volume = 118 | issue = 12B | pages = 54–8 | date = December 2005 | pmid = 16414327 | doi = 10.1016/j.amjmed.2005.09.033 }}</ref><ref>{{cite journal |last1=Rashid |first1=Tariq |last2=Haider |first2=Ijaz |title=Life Events and Depression |journal=Annals of Punjab Medical College |date=31 January 2008 |volume=2 |issue=1 |pages=11–16 |doi=10.29054/apmc/2008.621 |doi-broken-date=31 January 2024 |url=https://apmcfmu.com/index.php/apmc/article/view/621 |doi-access=free }}</ref><ref>{{cite journal | vauthors = Mata DA, Ramos MA, Bansal N, Khan R, Guille C, Di Angelantonio E, Sen S | title = Prevalence of Depression and Depressive Symptoms Among Resident Physicians: A Systematic Review and Meta-analysis | journal = JAMA | volume = 314 | issue = 22 | pages = 2373–83 | date = December 2015 | pmid = 26647259 | pmc = 4866499 | doi = 10.1001/jama.2015.15845 }}</ref><ref>{{Cite web|title=NIMH » Perinatal Depression|url=https://www.nimh.nih.gov/health/publications/perinatal-depression/index.shtml|access-date=29 October 2020|website=www.nimh.nih.gov|archive-date=27 March 2020|archive-url=https://web.archive.org/web/20200327041425/https://www.nimh.nih.gov/health/publications/perinatal-depression/index.shtml|url-status=live}}</ref><ref>{{Cite web|title=Postpartum Depression|url=https://medlineplus.gov/postpartumdepression.html|access-date=29 October 2020|website=medlineplus.gov|archive-date=27 July 2016|archive-url=https://web.archive.org/web/20160727211033/https://medlineplus.gov/postpartumdepression.html|url-status=live}}</ref> Adolescents may be especially prone to experiencing a depressed mood following [[social rejection]], peer pressure, or bullying.<ref>{{cite journal | vauthors = Davey CG, Yücel M, Allen NB | title = The emergence of depression in adolescence: development of the prefrontal cortex and the representation of reward | journal = Neuroscience and Biobehavioral Reviews | volume = 32 | issue = 1 | pages = 1–19 | year = 2008 | pmid = 17570526 | doi = 10.1016/j.neubiorev.2007.04.016 | s2cid = 20800688 }}</ref>

==== Childhood and adolescence ====
{{Main|Depression in childhood and adolescence}}
Depression in childhood and adolescence is similar to adult major depressive disorder, although young sufferers may exhibit increased irritability or behavioral dyscontrol instead of the more common sad, empty, or hopeless feelings seen with adults.<ref name="Birmaher">{{cite journal |display-authors=6 |vauthors=Birmaher B, Ryan ND, Williamson DE, Brent DA, Kaufman J, Dahl RE, Perel J, Nelson B |date=November 1996 |title=Childhood and adolescent depression: a review of the past 10 years. Part I |journal=Journal of the American Academy of Child and Adolescent Psychiatry |volume=35 |issue=11 |pages=1427–1439 |doi=10.1097/00004583-199611000-00011 |pmid=8936909 |s2cid=11623499}}</ref> Children who are under stress, experiencing loss, or have other underlying disorders are at a higher risk for depression. Childhood depression is often comorbid with [[mental disorders]] outside of other mood disorders; most commonly [[anxiety disorder]] and [[conduct disorder]]. Depression also tends to run in families.<ref>{{cite news |title=The Depressed Child |url=https://www.aacap.org/AACAP/Families_and_Youth/Facts_for_Families/FFF-Guide/The-Depressed-Child-4.aspx |work=Facts for Families |issue=4 |publisher=The American Academy of Child and Adolescent Psychiatry |date=July 2013 }}</ref>

=== Personality ===
Depression is associated with low [[extraversion]],<ref>{{cite journal | vauthors = Kotov R, Gamez W, Schmidt F, Watson D | title = Linking "big" personality traits to anxiety, depressive, and substance use disorders: a meta-analysis | journal = Psychological Bulletin | volume = 136 | issue = 5 | pages = 768–821 | date = September 2010 | pmid = 20804236 | doi = 10.1037/a0020327 }}</ref> and people who have high levels of [[neuroticism]] are more likely to experience depressive symptoms and are more likely to receive a diagnosis of a depressive disorder.<ref name="NeuroticismMA">{{cite journal | vauthors = Jeronimus BF, Kotov R, Riese H, Ormel J | title = Neuroticism's prospective association with mental disorders halves after adjustment for baseline symptoms and psychiatric history, but the adjusted association hardly decays with time: a meta-analysis on 59 longitudinal/prospective studies with 443 313 participants | journal = Psychological Medicine | volume = 46 | issue = 14 | pages = 2883–2906 | date = October 2016 | pmid = 27523506 | doi = 10.1017/S0033291716001653 | url = https://zenodo.org/record/895885 | s2cid = 23548727 | access-date = 5 July 2019 | archive-date = 29 December 2019 | archive-url = https://web.archive.org/web/20191229175420/https://zenodo.org/record/895885 | url-status = live }}</ref> Additionally, depression is associated with low conscientiousness. Some factors that may arise from low conscientiousness include disorganization and dissatisfaction with life. Individuals may be more exposed to stress and depression as a result of these factors.<ref>{{Cite web |last=Daze |first=Gilad |date=2022-03-08 |title=Explore the Impact of Depression Traits |url=https://www.brainsway.com/knowledge-center/personality-traits-associated-with-depression/ |access-date=2024-04-30 |website=BrainsWay |language=en-US}}</ref>

=== Side effect of medical treatment ===
It is possible that some early-generation [[beta-blocker]]s induce depression in some patients, though the evidence for this is weak and conflicting. There is strong evidence for a link between [[alpha interferon]] therapy and depression. One study found that a third of alpha interferon-treated patients had developed depression after three months of treatment. (''Beta'' interferon therapy appears to have no effect on rates of depression.) There is moderately strong evidence that [[finasteride]] when used in the treatment of alopecia increases depressive symptoms in some patients. Evidence linking [[isotretinoin]], an acne treatment, to depression is strong.<ref>{{cite journal | vauthors = Rogers D, Pies R | title = General Medical Drugs Associated with Depression  | journal = Psychiatry | volume = 5 | issue = 12 | pages = 28–41 | date = December 2008 | pmid = 19724774 | pmc = 2729620 }}</ref> Other medicines that seem to increase the risk of depression include [[anticonvulsants]], [[antimigraine drug]]s, [[antipsychotics]] and [[Hormone therapy|hormonal agents]] such as [[gonadotropin-releasing hormone agonist]].<ref>{{cite book |vauthors=Botts S, Ryan M |title=Drug-Induced Diseases Section IV: Drug-Induced Psychiatric Diseases Chapter 18: Depression |url=https://www.ashp.org/DocLibrary/Policy/Suicidality/DID-Chapter18.aspx |pages=1–23 |access-date=14 January 2017 |archive-url=https://web.archive.org/web/20101223035009/https://www.ashp.org/DocLibrary/Policy/Suicidality/DID-Chapter18.aspx |archive-date=23 December 2010 |url-status=dead }}</ref>

=== Substance-induced ===
Several drugs of abuse can cause or exacerbate depression, whether in intoxication, withdrawal, and from chronic use. These include alcohol, sedatives (including prescription benzodiazepines), opioids (including prescription pain killers and illicit drugs such as heroin), stimulants (such as cocaine and amphetamines), hallucinogens, and [[inhalants]].<ref>{{cite book |title=Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) |author=American Psychiatric Association |year=2013 |publisher=American Psychiatric Association |location=Arlington, VA}}{{page needed|date=July 2023}}</ref>

=== Non-psychiatric illnesses ===
{{main|Depression (differential diagnoses)}}
Depressed mood can be the result of a number of infectious diseases, [[Nutritional deficiency|nutritional deficiencies]], neurological conditions, and physiological problems, including [[hypoandrogenism]] (in men), [[Addison's disease]], [[Cushing's syndrome]], [[pernicious anemia]], [[hypothyroidism]], [[hyperparathyroidism]], [[Lyme disease]], [[multiple sclerosis]], [[Parkinson's disease]], [[celiac disease]],<ref>{{Cite journal |last1=Zingone |first1=Fabiana |last2=Swift |first2=Gillian L |last3=Card |first3=Timothy R |last4=Sanders |first4=David S |last5=Ludvigsson |first5=Jonas F |last6=Bai |first6=Julio C |date=April 2015 |title=Psychological morbidity of celiac disease: A review of the literature |journal=United European Gastroenterology Journal |language=en |volume=3 |issue=2 |pages=136–145 |doi=10.1177/2050640614560786 |issn=2050-6406 |pmc=4406898 |pmid=25922673}}</ref> chronic pain, stroke, diabetes, cancer, and HIV.<ref>Murray ED, Buttner N, Price BH. (2012) "Depression and Psychosis in Neurological Practice". In: Neurology in Clinical Practice, 6th Edition. Bradley WG, Daroff RB, Fenichel GM, Jankovic J (eds.) Butterworth Heinemann {{ISBN|978-1437704341}}{{page needed|date=November 2023}}</ref><ref>{{cite journal |vauthors=Rustad JK, Musselman DL, Nemeroff CB |date=October 2011 |title=The relationship of depression and diabetes: pathophysiological and treatment implications |journal=Psychoneuroendocrinology |volume=36 |issue=9 |pages=1276–86 |doi=10.1016/j.psyneuen.2011.03.005 |pmid=21474250 |s2cid=32439196}}</ref><ref>{{cite journal |vauthors=Li M, Fitzgerald P, Rodin G |date=April 2012 |title=Evidence-based treatment of depression in patients with cancer |journal=Journal of Clinical Oncology |volume=30 |issue=11 |pages=1187–96 |doi=10.1200/JCO.2011.39.7372 |pmid=22412144}}</ref>

Studies have found that anywhere from 30 to 85 percent of patients suffering from chronic pain are also clinically depressed.<ref>{{cite journal |last1=Sheng |first1=Jiyao |last2=Liu |first2=Shui |last3=Wang |first3=Yicun |last4=Cui |first4=Ranji |last5=Zhang |first5=Xuewen |title=The Link between Depression and Chronic Pain: Neural Mechanisms in the Brain |journal=Neural Plasticity |date=2017 |volume=2017 |pages=1–10 |doi=10.1155/2017/9724371 |pmc=5494581 |pmid=28706741 |doi-access=free }}</ref><ref>{{cite journal |last1=Surah |first1=A |last2=Baranidharan |first2=G |last3=Morley |first3=S |title=Chronic pain and depression |journal=Continuing Education in Anaesthesia Critical Care & Pain |date=April 2014 |volume=14 |issue=2 |pages=85–89 |doi=10.1093/bjaceaccp/mkt046 |doi-access=free }}</ref><ref>{{cite journal |last1=Holmes |first1=Alex |last2=Christelis |first2=Nicholas |last3=Arnold |first3=Carolyn |title=Depression and chronic pain |journal=Medical Journal of Australia |date=October 2013 |volume=199 |issue=S6 |pages=S17-20 |doi=10.5694/mja12.10589 |pmid=25370278 |s2cid=27576624 }}</ref> A 2014 study by Hooley et al. concluded that chronic pain increased the chance of death by suicide by two to three times.<ref>{{Cite web |last=U.S. Department of Veterans Affairs |date=2022 |title=Managing Chronic Pain May Protect Against Suicide Risk |url=https://www.mentalhealth.va.gov/suicide_prevention/docs/FSTP-Chronic-Pain.pdf}}</ref> In 2017, the British Medical Association found that 49% of UK chronic pain patients also had depression.<ref>{{Cite web |date=2017 |title=Chronic pain: supporting safer prescribing of analgesics |url=https://www.bma.org.uk/media/2100/analgesics-chronic-pain.pdf |publisher=British Medical Association}}</ref>

=== Psychiatric syndromes ===
{{Main|Mood disorder#Depressive disorders|l1=Depressive mood disorders}}
A number of psychiatric syndromes feature depressed mood as a main symptom. The [[mood disorder]]s are a group of disorders considered to be primary disturbances of mood. These include [[major depressive disorder]] (commonly called major depression or clinical depression) where a person has at least two weeks of depressed mood or a loss of interest or pleasure in nearly all activities; and [[dysthymia]], a state of chronic depressed mood, the symptoms of which do not meet the severity of a [[major depressive episode]]. Another mood disorder, [[bipolar disorder]], features one or more episodes of abnormally elevated mood, [[cognition]], and energy levels, but may also involve one or more episodes of depression.<ref>{{cite book | vauthors = Gabbard G |title=Treatment of Psychiatric Disorders |edition=3rd |volume=2 |publisher=American Psychiatric Publishing |location=Washington, DC |page=1296}}</ref> When the course of depressive episodes follows a seasonal pattern, the disorder (major depressive disorder, bipolar disorder, etc.) may be described as a [[seasonal affective disorder]].

Outside the mood disorders: [[borderline personality disorder]] often features an extremely intense depressive mood; [[Adjustment disorder|adjustment disorder with depressed mood]] is a psychological response to an identifiable event or stressor, in which the resulting emotional or behavioral symptoms are significant but do not meet the criteria for a major depressive episode;<ref>{{cite book |title=Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision: DSM-IV-TR |author=American Psychiatric Association |publisher=American Psychiatric Publishing, Inc. |location=Washington, DC |year=2000 |isbn=978-0890420256 |page=355}}</ref> and [[posttraumatic stress disorder]], a mental disorder that sometimes follows [[Major trauma|trauma]], is commonly accompanied by depressed mood.<ref>{{cite journal | vauthors = Vieweg WV, Julius DA, Fernandez A, Beatty-Brooks M, Hettema JM, Pandurangi AK | title = Posttraumatic stress disorder: clinical features, pathophysiology, and treatment | journal = The American Journal of Medicine | volume = 119 | issue = 5 | pages = 383–90 | date = May 2006 | pmid = 16651048 | doi = 10.1016/j.amjmed.2005.09.027 | doi-access = free }}</ref>

=== Inflammation ===
{{excerpt|Inflammation#|Connection to depression}}

=== Historical legacy ===
Researchers have begun to conceptualize ways in which the historical legacies of racism and colonialism may create depressive conditions.<ref>{{cite book | vauthors = Cvetkovich A |title=Depression: A Public Feeling |date=2012 |publisher=Duke University Press Books |location=Durham, NC |isbn=978-0-8223-5238-9 }}{{page needed|date=November 2023}}</ref><ref name=Cox2012/> Given the lived experiences of marginalized peoples, ranging from conditions of [[Human migration|migration]], [[class stratification]], [[cultural genocide]], [[labor exploitation]], and [[social mobility|social immobility]], depression can be seen as a "rational response to global conditions", according to [[Ann Cvetkovich]].<ref>{{cite book|last1=Cvetkovich|first1=Ann|title=Depression: A Public Feeling|date=2012|publisher=Duke University Press|location=Durham, NC|isbn=978-0822352389|oclc=779876753|page=25|quote=…the histories of genocide, slavery, and exclusion and oppression of immigrants that seep into our daily lives of segregation, often as invisible forces that structure comfort and privilege for some and lack of resources for others, inequities whose connection to the past frequently remain obscure. These are depressing conditions, indeed, ones that make depression seem not so much a medical or biochemical dysfunction as a very rational response to global conditions.|url=https://books.google.com/books?id=qn9jSPVRcDMC&pg=PA25}}</ref>

Psychogeographical depression overlaps somewhat with the theory of "deprejudice", a portmanteau of depression and [[prejudice]] proposed by Cox, Abramson, Devine, and Hollon in 2012,<ref name=Cox2012>{{cite journal|last1=Cox|first1=William T.L.|last2=Abramson|first2=Lyn Y.|last3=Devine|first3=Patricia G.|last4=Hollon|first4=Steven D.|title=Stereotypes, Prejudice, and Depression: The Integrated Perspective|journal=Perspectives on Psychological Science|volume=7|issue=5|pages=427–49|date=September 2012|doi=10.1177/1745691612455204|pmid=26168502|s2cid=1512121 }} {{Closed access}}</ref> who argue for an integrative approach to studying the often comorbid experiences. Cox, Abramson, Devine, and Hollon are concerned with the ways in which social [[stereotype]]s are often [[Internalisation (sociology)|internalized]], creating negative [[Self-stereotyping|self-stereotypes]] that then produce depressive symptoms.

Unlike the theory of "deprejudice", a psychogeographical theory of depression attempts to broaden study of the subject beyond an individual experience to one produced on a societal scale, seeing particular manifestations of depression as rooted in dispossession; historical legacies of [[genocide]], [[slavery]], and colonialism are productive of segregation, both material and psychic material deprivation,<ref>{{cite magazine | author=Ta-Nehisi Coates| url=https://www.theatlantic.com/magazine/archive/2014/06/the-case-for-reparations/361631/ | title=The Case for Reparations | magazine=The Atlantic | date=June 2014}}</ref> and concomitant circumstances of violence, systemic exclusion, and lack of access to legal protections. The demands of navigating these circumstances compromise the resources available to a population to seek comfort, health, stability, and sense of security. The historical memory of this [[psychological trauma|trauma]] conditions the psychological health of future generations, making psychogeographical depression an [[Transgenerational trauma|intergenerational]] experience as well. 
 
This work is supported by recent studies in genetic science which has demonstrated an [[epigenetic]] link between the trauma suffered by [[Holocaust survivor]]s and the genetic reverberations for subsequent generations.<ref>{{cite journal|last1=Yehuda|first1=Rachel|last2=Daskalakis|first2=Nikolaos P.|last3=Bierer|first3=Linda M.|last4=Bader|first4=Heather N.|last5=Klengel|first5=Torsten|last6=Holsboer|first6=Florian|last7=Binder|first7=Elisabeth B.|title=Holocaust Exposure Induced Intergenerational Effects on FKBP5 Methylation|journal=Biological Psychiatry|date=August 12, 2015|volume=80 |issue=5 |pages=372–380 |doi=10.1016/j.biopsych.2015.08.005|pmid=26410355|doi-access=free}} {{Closed access}}</ref>{{Primary source inline|date=May 2016}} Likewise, research by scientists at [[Emory University]] suggests that memories of trauma can be inherited, rendering offspring vulnerable to psychological predispositions for [[Psychological stress|stress disorder]]s, [[schizophrenia]], and [[Post-traumatic stress disorder|PTSD]].<ref>{{cite journal|last1=Callaway|first1=Ewen|title=Fearful Memories Haunt Mouse Descendants|journal=Nature|date=December 1, 2013|doi=10.1038/nature.2013.14272|s2cid=155233262 |url=http://www.nature.com/news/fearful-memories-haunt-mouse-descendants-1.14272}}</ref>

== Measures ==
Measures of depression include, but are not limited to: [[Beck Depression Inventory|Beck Depression Inventory-11]] and the 9-item depression scale in the [[Patient Health Questionnaire]] (PHQ-9).<ref>{{cite journal | vauthors = Kroenke K, Spitzer RL, Williams JB | title = The PHQ-9: validity of a brief depression severity measure | journal = Journal of General Internal Medicine | volume = 16 | issue = 9 | pages = 606–13 | date = September 2001 | pmid = 11556941 | pmc = 1495268 | doi = 10.1046/j.1525-1497.2001.016009606.x }}</ref> Both of these measures are psychological tests that ask personal questions of the participant, and have mostly been used to measure the severity of depression. The Beck Depression Inventory is a self-report scale that helps a therapist identify the patterns of depression symptoms and monitor recovery. The responses on this scale can be discussed in therapy to devise interventions for the most distressing symptoms of depression.<ref name=":1" />

== Theories ==
Schools of depression theories include:
* [[Beck's cognitive triad|Cognitive theory of depression]]
* [[Tripartite Model of Anxiety and Depression]]
* [[Behavioral theories of depression]]
* [[Evolutionary approaches to depression]]
* [[Biology of depression]]
* [[Epigenetics of depression]]

== Management ==
{{main|Management of depression}}
Depressed mood may not require professional treatment, and may be a normal temporary reaction to life events, a symptom of some medical condition, or a [[side effect]] of some drugs or medical treatments. A prolonged depressed mood, especially in combination with other symptoms, may lead to a diagnosis of a psychiatric or medical condition which may benefit from treatment. Many have linked depression to a life falling short of expectations and have blamed influencers for setting unrealistic expectations.<ref>{{Cite web |title=Dis-like: How Social Media Feeds into Perfectionism - Penn Medicine |url=https://www.pennmedicine.org/news/news-blog/2019/november/dis-like-how-social-media-feeds-into-perfectionism |access-date=9 November 2023 |website=www.pennmedicine.org |language=en-US}}</ref><ref>{{Cite web |last=Thompson |first=Derek |date=24 February 2019 |title=Workism Is Making Americans Miserable |url=https://www.theatlantic.com/ideas/archive/2019/02/religion-workism-making-americans-miserable/583441/ |access-date=9 November 2023 |website=The Atlantic |language=en}}</ref><ref>{{Cite web |last=marcomarce |date=22 June 2022 |title=Influencer Culture Is Selling The Myth of Meritocracy |url=https://nakedpolitics.co.uk/2022/06/22/influencer-culture-is-selling-the-myth-of-meritocracy/ |access-date=9 November 2023 |website=nakedpolitics.co.uk |language=en-US}}</ref>

The UK [[National Institute for Health and Care Excellence]] (NICE) 2009 guidelines indicate that [[antidepressant]]s should not be routinely used for the initial treatment of mild depression, because the risk-benefit ratio is poor.<ref>[https://www.nice.org.uk/guidance/cg90/chapter/key-priorities-for-implementation NICE guidelines, published October 2009] {{Webarchive|url=https://web.archive.org/web/20210121135808/https://www.nice.org.uk/guidance/cg90/chapter/Key-priorities-for-implementation |date=21 January 2021 }}. Nice.org.uk. Retrieved on 24 November 2015.</ref>

Physical activity has a protective effect against the emergence of depression in some people.<ref name=Sc2018>{{cite journal | vauthors = Schuch FB, Vancampfort D, Firth J, Rosenbaum S, Ward PB, Silva ES, Hallgren M, Ponce De Leon A, Dunn AL, Deslandes AC, Fleck MP, Carvalho AF, Stubbs B | display-authors = 6 | title = Physical Activity and Incident Depression: A Meta-Analysis of Prospective Cohort Studies | journal = The American Journal of Psychiatry | volume = 175 | issue = 7 | pages = 631–648 | date = July 2018 | pmid = 29690792 | doi = 10.1176/appi.ajp.2018.17111194 | doi-access = free }}</ref>

There is limited evidence suggesting yoga may help some people with depressive disorders or elevated levels of depression, but more research is needed.<ref>{{cite journal | vauthors = Cramer H, Lauche R, Langhorst J, Dobos G | title = Yoga for depression: a systematic review and meta-analysis | journal = Depression and Anxiety | volume = 30 | issue = 11 | pages = 1068–83 | date = November 2013 | pmid = 23922209 | doi = 10.1002/da.22166 | s2cid = 8892132 }}</ref><ref>{{cite journal | vauthors = Grensman A, Acharya BD, Wändell P, Nilsson GH, Falkenberg T, Sundin Ö, Werner S | title = Effect of traditional yoga, mindfulness-based cognitive therapy, and cognitive behavioral therapy, on health related quality of life: a randomized controlled trial on patients on sick leave because of burnout | journal = BMC Complementary and Alternative Medicine | volume = 18 | issue = 1 | pages = 80 | date = March 2018 | pmid = 29510704 | pmc = 5839058 | doi = 10.1186/s12906-018-2141-9 | doi-access = free }}</ref>

[[Reminiscence]] of old and fond memories is another alternative form of treatment, especially for the elderly who have lived longer and have more experiences in life. It is a method that causes a person to recollect memories of their own life, leading to a process of self-recognition and identifying familiar stimuli. By maintaining one's personal past and identity, it is a technique that stimulates people to view their lives in a more objective and balanced way, causing them to pay attention to positive information in their life stories, which would successfully reduce depressive mood levels.<ref>{{cite journal | vauthors = Viguer P, Satorres E, Fortuna FB, Meléndez JC | title = A Follow-Up Study of a Reminiscence Intervention and Its Effects on Depressed Mood, Life Satisfaction, and Well-Being in the Elderly | journal = The Journal of Psychology | volume = 151 | issue = 8 | pages = 789–803 | date = November 2017 | pmid = 29166223 | doi = 10.1080/00223980.2017.1393379 | s2cid = 21839684 }}</ref>

There is limited evidence that continuing antidepressant medication for one year reduces the risk of depression recurrence with no additional harm.<ref name=":4">{{cite journal | vauthors = Wilkinson P, Izmeth Z | title = Continuation and maintenance treatments for depression in older people | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | pages = CD006727 | date = September 2016 | issue = 9 | pmid = 27609183 | pmc = 6457610 | doi = 10.1002/14651858.cd006727.pub3 }}</ref> Recommendations for psychological treatments or combination treatments in preventing recurrence are not clear.<ref name=":4" />

==Epidemiology==
{{Main|Epidemiology of depression}}
Depression is the leading cause of disability worldwide, the United Nations (<span class="ltr">UN</span>) health agency reported, estimating that it affects more than 300 million people worldwide – the majority of them women, young people and the elderly. An estimated 4.4 percent of the global population has depression, according to a report released by the UN World Health Organization (WHO), which shows an 18 percent increase in the number of people living with depression between 2005 and 2015.<ref>{{Cite web |url=https://news.un.org/en/story/2017/02/552062-un-health-agency-reports-depression-now-leading-cause-disability-worldwide |title=UN health agency reports depression now 'leading cause of disability worldwide'|date=23 February 2017|website=UN News|language=en |access-date=27 June 2019|archive-date=27 June 2019|archive-url=https://web.archive.org/web/20190627090709/https://news.un.org/en/story/2017/02/552062-un-health-agency-reports-depression-now-leading-cause-disability-worldwide|url-status=live}}</ref><ref>{{cite news |last1=Solomon |first1=Andrew |title=Opinion {{!}} Our Great Depression |url=https://www.nytimes.com/2006/11/17/opinion/17solomon.html |work=The New York Times |date=17 November 2006 }}</ref><ref>{{cite news |agency=Agence France-Presse |title=Depression is leading cause of disability worldwide, says WHO study |url=https://www.theguardian.com/society/2017/mar/31/depression-is-leading-cause-of-disability-worldwide-says-who-study |work=The Guardian |date=31 March 2017 }}</ref>

Depression is a major mental-health cause of [[disease burden]]. Its consequences further lead to significant burden in [[public health]], including a higher risk of [[dementia]], premature mortality arising from physical disorders, and maternal depression impacts on child growth and development.<ref name=":2">{{cite journal | vauthors = Reynolds CF, Patel V | title = Screening for depression: the global mental health context | journal = World Psychiatry | volume = 16 | issue = 3 | pages = 316–317 | date = October 2017 | pmid = 28941110 | pmc = 5608832 | doi = 10.1002/wps.20459 }}</ref> Approximately 76% to 85% of depressed people in low- and middle-income countries do not receive treatment;<ref>{{cite journal | vauthors = Wang PS, Aguilar-Gaxiola S, Alonso J, Angermeyer MC, Borges G, Bromet EJ, Bruffaerts R, de Girolamo G, de Graaf R, Gureje O, Haro JM, Karam EG, Kessler RC, Kovess V, Lane MC, Lee S, Levinson D, Ono Y, Petukhova M, Posada-Villa J, Seedat S, Wells JE | display-authors = 6 | title = Use of mental health services for anxiety, mood, and substance disorders in 17 countries in the WHO world mental health surveys | journal = Lancet | volume = 370 | issue = 9590 | pages = 841–50 | date = September 2007 | pmid = 17826169 | pmc = 2847360 | doi = 10.1016/s0140-6736(<span class="ltr">07</span>)61414-7 }}</ref> barriers to treatment include: inaccurate assessment, lack of trained health-care providers, social stigma and lack of resources.<ref name=":3"/>

The stigma comes from misguided societal views that people with mental illness are different from everyone else, and they can choose to get better only if they wanted to.<ref>{{cite web |last1=Borenstein |first1=Jeffrey |title=Stigma, Prejudice and Discrimination Against People with Mental Illness |url=https://www.psychiatry.org/patients-families/stigma-and-discrimination |work=MakeItOK.org |publisher=American Psychiatric Association |date=August 2020 }}</ref> Due to this more than half of the people with depression do not receive help with their disorders. The stigma leads to a strong preference for privacy. An analysis of 40,350 undergraduates from 70 institutions by Posselt and Lipson found that undergraduates who perceived their classroom environments as highly competitive had a 37% higher chance of developing depression and a 69% higher chance of developing anxiety.<ref>{{cite journal |last1=Posselt |first1=Julie R. |last2=Lipson |first2=Sarah Ketchen |title=Competition, Anxiety, and Depression in the College Classroom: Variations by Student Identity and Field of Study |journal=Journal of College Student Development |date=2016 |volume=57 |issue=8 |pages=973–989 |id={{Project MUSE|638561}} |doi=10.1353/csd.2016.0094 |s2cid=151752884 }}</ref> Several studies have suggested that unemployment roughly doubles the risk of developing depression.<ref>{{Cite web |last=Pew Research Center |date=2010 |title=The Impact of Long-term Unemployment Lost Income, Lost Friends—and Loss of Self-respect |url=https://www.pewresearch.org/wp-content/uploads/sites/3/2010/11/760-recession.pdf}}</ref><ref>{{Cite web |title=Press Statement Irish Health Survey 2019 - Main Results - CSO - Central Statistics Office |url=https://www.cso.ie/en/csolatestnews/pressreleases/2020pressreleases/pressstatementirishhealthsurvey2019-mainresults/ |access-date=6 November 2023 |website=www.cso.ie |language=en}}</ref><ref>{{Cite web |last=Leopold |first=Les |date=17 January 2023 |title=Op-Ed: Being laid off is devastating. Yet society never measures that toll |url=https://www.latimes.com/opinion/story/2023-01-17/tech-layoffs-stress-trauma-unemployment-economy |access-date=6 November 2023 |website=Los Angeles Times |language=en-US}}</ref><ref>{{cite journal |last1=McGee |first1=Robin E. |last2=Thompson |first2=Nancy J. |title=Unemployment and Depression Among Emerging Adults in 12 States, Behavioral Risk Factor Surveillance System, 2010 |journal=Preventing Chronic Disease |date=19 March 2015 |volume=12 |pages=E38 |doi=10.5888/pcd12.140451 |pmid=25789499 |pmc=4372159 |doi-access=free }}</ref><ref>{{cite journal |last1=Farré |first1=Lídia |last2=Fasani |first2=Francesco |last3=Mueller |first3=Hannes |title=Feeling useless: the effect of unemployment on mental health in the Great Recession |journal=IZA Journal of Labor Economics |date=December 2018 |volume=7 |issue=1 |doi=10.1186/s40172-018-0068-5 |doi-access=free |hdl=10261/170378 |hdl-access=free }}</ref>

The World Health Organization has constructed guidelines – known as The Mental Health Gap Action Programme (mhGAP) – aiming to increase services for people with mental, neurological and substance-use disorders.<ref name=":3" /> Depression is listed as one of conditions prioritized by the programme. Trials conducted show possibilities for the implementation of the programme in low-resource primary-care settings dependent on primary-care practitioners and lay health-workers.<ref>
{{cite journal |display-authors=6 |vauthors=Patel V, Weobong B, Nadkarni A, Weiss HA, Anand A, Naik S, Bhat B, Pereira J, Araya R, Dimidjian S, Hollon SD, King M, McCambridge J, McDaid D, Murthy P, Velleman R, Fairburn CG, Kirkwood B |date=April 2014 |title=The effectiveness and cost-effectiveness of lay counsellor-delivered psychological treatments for harmful and dependent drinking and moderate to severe depression in primary care in India: PREMIUM study protocol for randomized controlled trials |journal=Trials |volume=15 |issue=1 |pages=101 |doi=10.1186/1745-6215-15-101 |pmc=4230277 |pmid=24690184 |doi-access=free}}
</ref>
Examples of mhGAP-endorsed therapies targeting depression include Group Interpersonal Therapy as group treatment for depression and "Thinking Health", which utilizes [[cognitive behavioral therapy]] to tackle perinatal depression.<ref name=":3" /> Furthermore, effective screening in primary care is crucial for the access of treatments. The mhGAP adopted its approach of improving detection rates of depression by training general practitioners. However, there is still weak evidence supporting this training.<ref name=":2" />

According to 2011 study, people who are high in [[Competition|hypercompetitive]] traits are also likely to measure higher for depression and anxiety.<ref>{{Cite news |date=8 September 2022 |title=Perspective {{!}} Yes, you can be too competitive. Here's why, and how to stop. |language=en-US |newspaper=[[The Washington Post]] |url=https://www.washingtonpost.com/lifestyle/2021/11/01/too-competitive-tips/ |access-date=9 November 2023 }}</ref>

== History ==
{{Main|History of depression}}The term ''depression'' was derived from the Latin verb {{lang|la|deprimere}}, "to press down".<ref>depress. (n.d.). Online Etymology Dictionary. Retrieved 30 June 2008, from [http://dictionary.reference.com/browse/depress dictionary.com]</ref> From the 14th&nbsp;century, "to depress" meant to subjugate or to bring down in spirits. It was used in 1665 in English author [[Richard Baker (chronicler)|Richard Baker's]] ''Chronicle'' to refer to someone having "a great depression of spirit", and by English author [[Samuel Johnson]] in a similar sense in 1753.<ref>{{cite news |author=Wolpert, L. |title=Malignant Sadness: The Anatomy of Depression |work=The New York Times |url=https://www.nytimes.com/books/first/w/wolpert-sadness.html |access-date=30 October 2008}}</ref>

In Ancient Greece, disease was thought due to an imbalance in the four basic bodily fluids, or ''[[Humorism|humors]]''. Personality types were similarly thought to be determined by the dominant humor in a particular person. Derived from the [[Ancient Greek]] {{lang|grc-Latn|melas}}, "black", and {{lang|grc-Latn|kholé}}, "bile",<ref name="Liddell1980">{{cite book |author1=[[Henry Liddell|Liddell, Henry]] |author2=[[Robert Scott (philologist)|Robert Scott]] |url=https://archive.org/details/lexicon00lidd |title=A Greek-English Lexicon |publisher=[[Oxford University Press]] |year=1980 |isbn=0-19-910207-4 |edition=Abridged |location=United Kingdom}}</ref> [[melancholia]] was described as a distinct disease with particular mental and physical symptoms by [[Hippocrates]] in his ''Aphorisms'', where he characterized all "fears and despondencies, if they last a long time" as being symptomatic of the ailment.<ref>Hippocrates, ''Aphorisms'', Section 6.23</ref>

During the 18th century, the humoral theory of melancholia was increasingly being challenged by mechanical and electrical explanations; references to dark and gloomy states gave way to ideas of slowed circulation and depleted energy.<ref name="Jackson83">{{cite journal |vauthors=Jackson SW |date=July 1983 |title=Melancholia and mechanical explanation in eighteenth-century medicine |journal=Journal of the History of Medicine and Allied Sciences |volume=38 |issue=3 |pages=298–319 |doi=10.1093/jhmas/38.3.298 |pmid=6350428}}</ref> German physician [[Johann Christian August Heinroth|Johann Christian Heinroth]], however, argued melancholia was a disturbance of the soul due to moral conflict within the patient.

In the 20th century, the German psychiatrist Emil Kraepelin distinguished manic depression. The influential system put forward by Kraepelin unified nearly all types of mood disorder into ''manic–depressive insanity''. Kraepelin worked from an assumption of underlying brain pathology, but also promoted a distinction between [[endogenous]] (internally caused) and [[exogenous]] (externally caused) types.<ref name="Davison20062">{{cite journal |vauthors=Davison K |year=2006 |title=Historical aspects of mood disorders |journal=Psychiatry |volume=5 |issue=4 |pages=115–18 |doi=10.1383/psyt.2006.5.4.115}}</ref>

Other psycho-dynamic theories were proposed. [[Existential psychology|Existential]] and [[Humanistic psychology|humanistic]] theories represented a forceful affirmation of individualism.<ref>{{cite book |last1=Covi |first1=Lino |chapter=The Depressive Syndromes: An Overview |pages=41–78 [64, 66] |chapter-url=https://books.google.com/books?id=JmjjTgW7DG0C&pg=PA64 |editor1-last=Freeman |editor1-first=Arthur |editor2-last=Epstein |editor2-first=Norman |editor3-last=Simon |editor3-first=Karen M |title=Depression in the Family |date=1986 |publisher=Psychology Press |isbn=978-0-86656-624-7 }}</ref> Austrian existential psychiatrist [[Viktor Frankl]] connected depression to feelings of futility and [[Meaning (existential)|meaninglessness]].<ref name="Frankl">{{cite book |vauthors=Frankl VE |title=Man's search for ultimate meaning |publisher=Basic Books |year=2000 |isbn=0-7382-0354-8 |location=New York, NY, USA |pages=139–40}}</ref> Frankl's [[logotherapy]] addressed the filling of an "existential vacuum" associated with such feelings, and may be particularly useful for depressed adolescents.<ref>Seidner, Stanley S. (10 June 2009) [https://docs.google.com/gview?a=v&q=cache:FrKYAo88ckkJ:www.materdei.ie/media/conferences/a-secular-age-parallel-sessions-timetable.pdf+%22Stan+Seidner%22&hl=en&gl=us "A Trojan Horse: Logotherapeutic Transcendence and its Secular Implications for Theology"] {{Webarchive|url=https://web.archive.org/web/20110501081407/http://docs.google.com/gview?a=v&q=cache%3AFrKYAo88ckkJ%3Awww.materdei.ie%2Fmedia%2Fconferences%2Fa-secular-age-parallel-sessions-timetable.pdf+%22Stan+Seidner%22&hl=en&gl=us |date=1 May 2011 }}. ''Mater Dei Institute''. pp 14–15.</ref><ref>{{cite journal |vauthors=Blair RG |date=October 2004 |title=Helping older adolescents search for meaning in depression |journal=Journal of Mental Health Counseling |volume=26 |issue=4 |pages=333–347 |doi=10.17744/mehc.26.4.w8u9h6uf5ybhapyl}}</ref>

Researchers theorized that depression was caused by a [[Chemical imbalance theory|chemical imbalance]] in neurotransmitters in the brain, a theory based on observations made in the 1950s of the effects of [[reserpine]] and [[isoniazid]] in altering monoamine neurotransmitter levels and affecting depressive symptoms.<ref>{{cite journal |vauthors=Schildkraut JJ |year=1965 |title=The catecholamine hypothesis of affective disorders: A review of supporting evidence |journal=American Journal of Psychiatry |volume=122 |issue=5 |pages=509–22 |doi=10.1176/ajp.122.5.509 |pmid=5319766}}</ref> During the 1960s and 70s, manic-depression came to refer to just one type of mood disorder (now most commonly known as [[bipolar disorder]]) which was distinguished from (unipolar) depression. The terms unipolar and bipolar had been coined by German psychiatrist [[Karl Kleist]].<ref name="Davison20062"/>

In July 2022, British psychiatrist [[Joanna Moncrieff]], also psychiatrist Mark Horowtiz and others proposed in a study on academic journal ''[[Molecular Psychiatry]]'' that depression is not caused by a serotonin imbalance in the human body, unlike what most of the psychiatry community points to, and that therefore anti-depressants do not work against the illness.<ref>{{cite journal |last1=Moncrieff |first1=Joanna |last2=Cooper |first2=Ruth E. |last3=Stockmann |first3=Tom |last4=Amendola |first4=Simone |last5=Hengartner |first5=Michael P. |last6=Horowitz |first6=Mark A. |title=The serotonin theory of depression: a systematic umbrella review of the evidence |journal=Molecular Psychiatry |date=August 2023 |volume=28 |issue=8 |pages=3243–3256 |doi=10.1038/s41380-022-01661-0 |pmid=35854107 |pmc=10618090 |s2cid=250646781 |doi-access=free }}</ref><ref>{{Cite web |last1=Moncrieff |first1=Joanna |last2=Horowitz |first2=Mark |title=Depression is probably not caused by a chemical imbalance in the brain – new study |url=http://theconversation.com/depression-is-probably-not-caused-by-a-chemical-imbalance-in-the-brain-new-study-186672 |access-date=11 August 2022 |website=The Conversation |date=20 July 2022 |language=en}}</ref> However, such study was met with criticism from some psychiatrists, who argued the study's methodology used an indirect trace of serotonin, instead of taking direct measurements of the molecule.<ref name=":5">{{cite news |title=Study on serotonin and depression sparks fierce debate |url=https://www.france24.com/en/live-news/20220811-study-on-serotonin-and-depression-sparks-fierce-debate |work=France 24 |agency=AFP |date=11 August 2022 }}</ref> Moncrieff said that, despite her study's conclusions, no one should interrupt their treatment if they are taking any anti-depressant.<ref name=":5" />

== See also ==
* [[Alain Ehrenberg]], French sociologist, author of ''Weariness of the Self: Diagnosing the History of Depression in the Contemporary Age''
* {{Annotated link|Attribution (psychology)}}
* {{Annotated link|Biopsychosocial model}}
* {{Annotated link|Depression in childhood and adolescence}}
* {{Annotated link|Diathesis–stress model}}
* {{Annotated link|Existential crisis}}
* {{Annotated link|Feeling}}
* {{Annotated link|Locus of control}}
* {{Annotated link|Melancholia}}
* {{Annotated link|Mixed anxiety–depressive disorder}}

== References ==
{{reflist|30em}}

== External links ==
{{wikiquote|Depression}}
* {{Commons category-inline|Depression (mood)}}

{{Medical condition classification and resources
| DiseasesDB      =3589
| ICD11           = {{ICD11|6A7|1563440232}}
| ICD10           = {{ICD10|F32}}, {{ICD10|F33}}
| ICD9            = <!-- {{ICD9|xxx}} -->
| ICDO            =
| OMIM            =
| MedlinePlus     =
| MeshID          =D003863
| GeneReviewsNBK  =
| GeneReviewsName =
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[[Category:Depression (mood)| ]]
[[Category:Emotions]]
[[Category:Neuropsychology]]
[[Category:Mental states]]
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