Chinese, Mandarin

Spanish

English

Hindi

Arabic

Portuguese

Bengali

Russian

Japanese

Punjabi

German

Javanese

Malay

Telugu

Vietnamese

Korean

French

Marathi

Tamil

Urdu

Turkish

Italian

Chinese, Yue / Cantonese

Thai

Gujarati

Chinese, Jin

Chinese, Min Nan

Persian, Dari

Persian, Western

Polish

Pashto

Kannada

Chinese, Xiang

Malayalam

Sundanese

Hausa

Odia

Burmese

Chinese, Hakka

Ukrainian

Bihari, Bhojpuri

Tagalog

Yoruba

Bihari, Maithili

Uzbek

Sindhi

Amharic

Fula

Romanian

Oromo

Igbo

Azerbaijani

Chinese, Gan

Dutch

Kurdish, Central

Kurdish, Northern

Kurdish, Southern

Malagasy

Lahnda, Saraiki

Nepali

Sinhalese

Chittagonian

Zhuang

Khmer

Turkmen

Assamese

Madurese

Somali

Marwari

Bihari, Magahi

Haryanvi

Hungarian

Chhattisgarhi

Greek, Modern

Chewa

Dakhini

Akan, Twi

Akan, Fante

Kazakh

Chinese, Min Bei

Sylheti

Zulu

Czech

Kinyarwanda

Marwari, Dhundhari

Haitian Creole

Chinese, Min Dong

Ilocano

Quechua

Kirundi

Swedish

Hmong

Shona

Uyghur

Hiligaynon

Mossi

Xhosa

Belarusian

Balochi

Psychology

<OpenstaxParagraph>
	According to the DSM-5, the defining symptoms of <OpenstaxTerm>major depressive disorder</OpenstaxTerm> include “depressed mood most of the day, nearly every day” (feeling sad, empty, hopeless, or appearing tearful to others), and loss of interest and pleasure in usual activities (APA, 2013). In addition to feeling overwhelmingly sad most of each day, people with depression will no longer show interest or enjoyment in activities that previously were gratifying, such as hobbies, sports, sex, social events, time spent with family, and so on. Friends and family members may notice that the person has completely abandoned previously enjoyed hobbies; for example, an avid tennis player who develops major depressive disorder no longer plays tennis (Rothschild, 1999). 
</OpenstaxParagraph>
<OpenstaxParagraph>
	To receive a diagnosis of major depressive disorder, a person must, for at least two weeks, have a depressed mood and/or a loss of interest or pleasure in most activities. In addition, the person will show signs and symptoms of several of the following: significant weight loss or weight gain, insomnia or hypersomnia, psychomotor agitation (such as fidgeting, inability to sit, pacing, hand-wringing) or psychomotor retardation (such as talking and moving slowly), fatigue, feelings of worthlessness or guilt, difficulty concentrating or indecisiveness, and <OpenstaxTerm>suicidal ideation</OpenstaxTerm>.
</OpenstaxParagraph>
<OpenstaxParagraph>
	Major depressive disorder is considered episodic: its symptoms are typically present at their full magnitude for a certain period of time and then gradually abate. Approximately 50%–60% of people who experience an episode of major depressive disorder will have a second episode at some point in the future; those who have had two episodes have a 70% chance of having a third episode, and those who have had three episodes have a 90% chance of having a fourth episode (Rothschild, 1999). Although the episodes can last for months, a majority of people diagnosed with this condition (around 70%) recover within a year. However, a substantial number do not recover; around 12% show serious signs of impairment associated with major depressive disorder after 5 years (Boland &amp; Keller, 2009). In the long-term, many who do recover will still show minor symptoms that fluctuate in their severity (Judd, 2012). 
</OpenstaxParagraph>
<OpenstaxH3>Results of Major Depressive Disorder</OpenstaxH3>
<OpenstaxParagraph>
	Major depressive disorder is a serious and incapacitating condition that can have a devastating effect on the quality of one’s life. The person suffering from this disorder lives a profoundly miserable existence that often results in unavailability for work or education, abandonment of promising careers, and lost wages; occasionally, the condition requires hospitalization. The majority of those with major depressive disorder report having faced some kind of discrimination, and many report that having received such treatment has stopped them from initiating close relationships, applying for jobs for which they are qualified, and applying for education or training (Lasalvia et al., 2013). Major depressive disorder also takes a toll on health. Depression is a risk factor for the development of heart disease in healthy patients, as well as adverse cardiovascular outcomes in patients with preexisting heart disease (Whooley, 2006). 
</OpenstaxParagraph>
<OpenstaxH3>Risk Factors for Major Depressive Disorder</OpenstaxH3>
<OpenstaxParagraph>
	Major depressive disorder is often referred to as the common cold of psychiatric disorders. Around 6.6% of the U.S. population experiences major depressive disorder each year; 16.9% will experience the disorder during their lifetime (Kessler &amp; Wang, 2009). It is more common among women than among men, affecting approximately 20% of women and 13% of men at some point in their life (National Comorbidity Survey, 2007). The greater risk among women is not accounted for by a tendency to report symptoms or to seek help more readily, suggesting that gender differences in the rates of major depressive disorder may reflect biological and gender-related environmental experiences (Kessler, 2003). 
</OpenstaxParagraph>
<OpenstaxParagraph>
	Lifetime rates of major depressive disorder tend to be highest in North and South America, Europe, and Australia; they are considerably lower in Asian countries (Hasin, Fenton, &amp; Weissman, 2011). The rates of major depressive disorder are higher among younger age cohorts than among older cohorts, perhaps because people in younger age cohorts are more willing to admit depression (Kessler &amp; Wang, 2009). 
</OpenstaxParagraph>
<OpenstaxParagraph>
	A number of risk factors are associated with major depressive disorder: unemployment (including homemakers); earning less than $20,000 per year; living in urban areas; or being separated, divorced, or widowed (Hasin et al., 2011). Comorbid disorders include anxiety disorders and substance abuse disorders (Kessler &amp; Wang, 2009). 
</OpenstaxParagraph>

15.7.1 Major Depressive Disorder

1 Introduction to Psychology

1.1 What Is Psychology?

1.1.1 Why Study Psychology?

1.2 History of Psychology

1.2.1 Wundt and Structuralism

1.2.2 Functionalism

1.2.3 Freud and Psychoanalytic Theory

1.2.4 Wertheimer, Koffka, Köhler, and Gestalt Psychology

1.2.5 Pavlov, Watson, Skinner, and Behaviorism

1.2.6 Maslow, Rogers, and Humanism

1.2.7 The Cognitive Revolution

1.2.8 Multicultural And Cross-Cultural Psychology

1.2.9 Women in Psychology

1.3 Contemporary Psychology

1.3.1 Biopsychology and Evolutionary Psychology

1.3.2 Sensation and Perception

1.3.3 Cognitive Psychology

1.3.4 Developmental Psychology

1.3.5 Personality Psychology

1.3.6 Social Psychology

1.3.7 Industrial-Organizational Psychology

1.3.8 Health Psychology

1.3.9 Sport and Exercise Psychology

1.3.10 Clinical Psychology

1.3.11 Forensic Psychology

1.4 Careers in Psychology

1.4.1 Other Careers in Academic Settings

1.4.2 Career Options Outside of Academic Settings

2 Psychological Research

2.1 Why Is Research Important?

2.1.1 Use of Research Information

2.1.2 NOTABLE RESEARCHERS

2.1.3 The Process of Scientific Research

2.2 Approaches to Research

2.2.1 Clinical or Case Studies

2.2.2 Naturalistic Observation

2.2.3 Surveys

2.2.4 Archival Research

2.2.5 Longitudinal and Cross-Sectional Research

2.3 Analyzing Findings

2.3.1 Correlational Research

2.3.2 Causality: Conducting Experiments and Using the Data

2.3.3 Reliability and Validity

2.4 Ethics

2.4.1 Research Involving Human Participants

2.4.2 Research Involving Animal Subjects

3 Biopsychology

3.1 Human Genetics

3.1.1 Genetic Variation

3.1.2 Gene-Environment Interactions

3.2 Cells of the Nervous System

3.2.1 Neuron Structure

3.2.2 Neuronal Communication

3.2.3 Neurotransmitters and Drugs

3.3 Parts of the Nervous System

3.3.1 Peripheral Nervous System

3.4 The Brain and Spinal Cord

3.4.1 The Spinal Cord

3.4.2 The Two Hemispheres

3.4.3 Forebrain Structures

3.4.4 Midbrain and Hindbrain Structures

3.4.5 Brain Imaging

3.5 The Endocrine System

3.5.1 Major Glands

4 States of Consciousness

4.1 What Is Consciousness?

4.1.1 Biological Rhythms

4.1.2 Problems With Circadian Rhythms

4.2 Sleep and Why We Sleep

4.2.1 What is Sleep?

4.2.2 Why Do We Sleep?

4.3 Stages of Sleep

4.3.1 NREM Stages of Sleep

4.3.2 REM Sleep

4.4 Sleep Problems and Disorders

4.4.1 Insomnia

4.4.2 Parasomnias

4.4.3 Sleep Apnea

4.4.4 Narcolepsy

4.5 Substance Use and Abuse

4.5.1 Substance Use Disorders

4.5.2 Drug Categories

4.6 Other States of Consciousness

4.6.1 Hypnosis

4.6.2 Meditation

5 Sensation and Perception

5.1 Sensation versus Perception

5.1.1 Sensation

5.1.2 Perception

5.2 Waves and Wavelengths

5.2.1 Amplitude and Wavelength

5.2.2 Light Waves

5.2.3 Sound Waves

5.3 Vision

5.3.1 Anatomy of the Visual System

5.3.2 Color and Depth Perception

5.4 Hearing

5.4.1 Anatomy of the Auditory System

5.4.2 Pitch Perception

Question	Answer
commonly referred to as “depression” or “major depression,” characterized by sadness or loss of pleasure in usual activities, as well other symptoms	major depressive disorder
thoughts of death by suicide, thinking about or planning suicide, or making a suicide attempt	suicidal ideation