Anxiety

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Anxiety
Emperor Traianus Decius (Mary Harrsch).jpg

A marble bust of the Roman Emperor Decius from the Capitoline Museum. This portrait "conveys an impression of anxiety and weariness, as of a man shouldering heavy [state] responsibilities".[1]
MedlinePlus 003211 000917
MeSH D001007

Anxiety is an unpleasant state of inner turmoil, often accompanied by nervous behavior, such as pacing back and forth, somatic complaints and rumination.[2] It is the subjectively unpleasant feelings of dread over something unlikely to happen, such as the feeling of imminent death.[3] Anxiety is not the same as fear, which is felt about something realistically intimidating or dangerous and is an appropriate response to a perceived threat;[4] anxiety is a feeling of fear, worry, and uneasiness, usually generalized and unfocused as an overreaction to a situation that is only subjectively seen as menacing.[5] It is often accompanied by restlessness, fatigue, problems in concentration, and muscular tension. Anxiety is not considered to be a normal reaction to a perceived stressor although many feel it occasionally.

Signs and symptoms[edit]

A job applicant with a worried facial expression

Anxiety is a mental disorder, that is, characterized by excessive, uncontrollable and often irrational worry about everyday things that is disproportionate to the actual source of worry, it is diagnosed as generalized anxiety disorder (GAD). GAD occurs without an identifiable triggering stimulus. It is called generalized because the remorseless worries are not focused on any specific[6] threat; they are, in fact, often exaggerated and irrational. It is distinguished from fear, which is an appropriate cognitive and emotional response to a perceived threat and is related to the specific behaviors of fight-or-flight responses, defensive behavior or escape. Anxiety occurs in situations only perceived as uncontrollable or unavoidable, but not realistically so.[7] David Barlow defines anxiety as "a future-oriented mood state in which one is ready or prepared to attempt to cope with upcoming negative events,"[8] and that it is a distinction between future and present dangers which divides anxiety and fear. In a 2011 review of the literature,[9] fear and anxiety were said to be differentiated in four domains: (1) duration of emotional experience, (2) temporal focus, (3) specificity of the threat, and (4) motivated direction. Fear is defined as short lived, present focused, geared towards a specific threat, and facilitating escape from threat; while anxiety is defined as long acting, future focused, broadly focused towards a diffuse threat, and promoting excessive caution while approaching a potential threat and interferes with constructive coping. While almost everyone has experienced anxiety at some point in their lives, most do not develop long-term problems with anxiety. If long term or severe problems with anxiety develop, such problems are classified as an Anxiety disorder. Symptoms of anxiety can range in number, intensity, and frequency, depending on the person.

Subtypes of anxiety disorders are phobias, social anxiety, obsessive-compulsive behavior, and Posttraumatic stress disorder.[4] The physical effects of anxiety may include heart palpitations, tachycardia, muscle weakness and tension, fatigue, nausea, chest pain, shortness of breath, headache, stomach aches, or tension headaches. As the body prepares to deal with a threat, blood pressure, heart rate, perspiration, blood flow to the major muscle groups are increased, while immune and digestive functions are inhibited (the fight or flight response). External signs of anxiety may include pallor, sweating, trembling, and pupillary dilation. For someone who suffers anxiety this can lead to a panic attack. Sir Aubrey Lewis even suggests that "anxiety" could be defined as agony, dread, terror, or even apprehension.[10]

Although panic attacks are not experienced by every person who suffers from anxiety, they are a common symptom. Panic attacks usually come without warning and although the fear is generally irrational, the subjective perception of danger is very real. A person experiencing a panic attack will often feel as if he or she is about to die or lose consciousness. Between panic attacks, people with panic disorder tend to suffer from anticipated anxiety- a fear of having a panic attack may lead to the development of phobias.[11] Such a phobia is called agoraphobia, this is a fear of having a panic attack in a public place or new environment and experiencing judgement from strangers or failing to attain help.[12] Anxiety is the most common mental illness in America as approximately 40 million adults are affected by it.[4] Not only is anxiety common in adults, but it has also been found to be more common in females rather than males.[13]

A young woman bites her fingernails.
Nervous habits such as biting fingernails

The behavioral effects of anxiety may include withdrawal from situations which have provoked anxiety in the past.[14] Anxiety can also be experienced in ways which include changes in sleeping patterns, nervous habits, and increased motor tension like foot tapping.[14]

The emotional effects of anxiety may include "feelings of apprehension or dread, trouble concentrating, feeling tense or jumpy, anticipating the worst, irritability, restlessness, watching (and waiting) for signs (and occurrences) of danger, and, feeling like your mind's gone blank"[15] as well as "nightmares/bad dreams, obsessions about sensations, deja vu, a trapped in your mind feeling, and feeling like everything is scary."[16]

The cognitive effects of anxiety may include thoughts about suspected dangers, such as fear of dying. "You may ... fear that the chest pains are a deadly heart attack or that the shooting pains in your head are the result of a tumor or aneurysm. You feel an intense fear when you think of dying, or you may think of it more often than normal, or can't get it out of your mind."[17]

Causes[edit]

Early life experiences[edit]

Anxiety risk factors include family history (e.g. of anxiety)[18] and parenting factors including parental rejection, lack of parental warmth, high hostility, harsh discipline, high maternal negative affect, anxious childrearing, modelling of dysfunctional and drug-abusing behaviour, and child abuse (emotional, physical and sexual).[19]

Biological vulnerabilities[edit]

Research upon adolescents who as infants had been highly apprehensive, vigilant, and fearful finds that their nucleus accumbens is more sensitive than that in other people when deciding to make an action that determined whether they received a reward.[20] This suggests a link between circuits responsible for fear and also reward in anxious people. As researchers note, "a sense of 'responsibility', or self agency, in a context of uncertainty (probabilistic outcomes) drives the neural system underlying appetitive motivation (i.e., nucleus accumbens) more strongly in temperamentally inhibited than noninhibited adolescents".[20] Anxiety is also linked and perpetuated by the person's own pessimistic outcome expectancy and how they cope with feedback negativity.[21] Temperament and attitudes (e.g. pessimism) have been found to be risk factors for anxiety.[18] The psychologist David H. Barlow of Boston University conducted a study that showed three common characteristics of people suffering from chronic anxiety, which he characterized as "a generalized biological vulnerability", "a generalized psychological vulnerability", and "a specific psychological vulnerability".[22] While chemical issues in the brain that result in anxiety (especially resulting from genetics) are well documented,[citation needed] this study highlights an additional environmental factor that may result from being raised by parents suffering from chronic anxiety.[original research?]

Social issues - gender[edit]

Other contextual factors that are thought to contribute to anxiety include gender socialization and learning experiences. In particular, learning mastery (the degree to which people perceive their lives to be under their own control) and instrumentality, which includes such traits as self-confidence, independence, and competitiveness fully mediate the relation between gender and anxiety. That is, though gender differences in anxiety exist, with higher levels of anxiety in women compared to men, gender socialization and learning mastery explain these gender differences[citation needed]. Research has demonstrated the ways in which facial prominence in photographic images differs between men and women. More specifically, in official online photographs of politicians around the world, women's faces are less prominent than men's. Interestingly enough, the difference in these images actually tended to be greater in cultures with greater institutional gender equality.[23]

Evolutionary psychology[edit]

An evolutionary psychology explanation is that increased anxiety serves the purpose of increased vigilance regarding potential threats in the environment as well as increased tendency to take proactive actions regarding such possible threats. This may cause false positive reactions but an individual suffering from anxiety may also avoid real threats. This may explain why anxious people are less likely to die due to accidents.[24]

Neural circuitry involving the amygdala and hippocampus is thought to underlie anxiety.[25] When people are confronted with unpleasant and potentially harmful stimuli such as foul odors or tastes, PET-scans show increased bloodflow in the amygdala.[26][27] In these studies, the participants also reported moderate anxiety. This might indicate that anxiety is a protective mechanism designed to prevent the organism from engaging in potentially harmful behaviors.[original research?]

Genes[edit]

Although single genes have little effect on complex traits and interact heavily both between themselves and with the external factors, research is under-way to unravel possible molecular mechanisms underlying anxiety and comorbid conditions. One candidate gene with polymorphisms that influence anxiety is PLXNA2.[28]

Use of caffeine[edit]

Caffeine may cause or exacerbate anxiety disorders.[29][30] A number of clinical studies have shown a positive association between caffeine and anxiogenic effects and/or panic disorder.[31][32][32] Anxiety sufferers can have high caffeine sensitivity.[33][34][35][36][37]

Life experiences and overpotentiation[edit]

Some writers believe that excessive anxiety can lead to an overpotentiation of the limbic system, giving increased future anxiety, but this does not appear to have been proven.[38][39]

Types[edit]

Medical[edit]

Anxiety can be a symptom of an underlying health problems such as chronic obstructive pulmonary disease (COPD), heart failure, or heart arrythmia.[40]

Abnormal and pathological anxiety or fear may itself be a medical condition falling under the blanket term "anxiety disorder". Such conditions came under the aegis of psychiatry at the end of the 19th century[41] and current psychiatric diagnostic criteria recognize several specific forms of the disorder. Recent surveys have found that as many as 18% of Americans may be affected by one or more of them.[42]

Standardized screening tools such as Zung Self-Rating Anxiety Scale, Beck Anxiety Inventory, Taylor Manifest Anxiety Scale and HAM-A (Hamilton Anxiety Scale) can be used to detect anxiety symptoms and suggest the need for a formal diagnostic assessment of anxiety disorder.[43] The HAM-A (Hamilton Anxiety Scale) measures the severity of a patient's anxiety, based on 14 parameters, including anxious mood, tension, fears, insomnia, somatic complaints and behavior at the interview.[44]

Existential[edit]

The philosopher Søren Kierkegaard, in The Concept of Anxiety, described anxiety or dread associated with the "dizziness of freedom" and suggested the possibility for positive resolution of anxiety through the self-conscious exercise of responsibility and choosing. In Art and Artist (1932), the psychologist Otto Rank wrote that the psychological trauma of birth was the pre-eminent human symbol of existential anxiety and encompasses the creative person's simultaneous fear of – and desire for – separation, individuation and differentiation.

The theologian Paul Tillich characterized existential anxiety[45] as "the state in which a being is aware of its possible nonbeing" and he listed three categories for the nonbeing and resulting anxiety: ontic (fate and death), moral (guilt and condemnation), and spiritual (emptiness and meaninglessness). According to Tillich, the last of these three types of existential anxiety, i.e. spiritual anxiety, is predominant in modern times while the others were predominant in earlier periods. Tillich argues that this anxiety can be accepted as part of the human condition or it can be resisted but with negative consequences. In its pathological form, spiritual anxiety may tend to "drive the person toward the creation of certitude in systems of meaning which are supported by tradition and authority" even though such "undoubted certitude is not built on the rock of reality".[45]

According to Viktor Frankl, the author of Man's Search for Meaning, when a person is faced with extreme mortal dangers, the most basic of all human wishes is to find a meaning of life to combat the "trauma of nonbeing" as death is near.[citation needed]

Test and performance[edit]

According to Yerkes-Dodson law, an optimal level of arousal is necessary to best complete a task such as an exam, performance, or competitive event. However, when the anxiety or level of arousal exceeds that optimum, the result is a decline in performance.[46]

Test anxiety is the uneasiness, apprehension, or nervousness felt by students who have a fear of failing an exam. Students who have test anxiety may experience any of the following: the association of grades with personal worth; fear of embarrassment by a teacher; fear of alienation from parents or friends; time pressures; or feeling a loss of control. Sweating, dizziness, headaches, racing heartbeats, nausea, fidgeting, uncontrollable crying or laughing and drumming on a desk are all common. Because test anxiety hinges on fear of negative evaluation,[47] debate exists as to whether test anxiety is itself a unique anxiety disorder or whether it is a specific type of social phobia.[48] The DSM-IV classifies test anxiety as a type of social phobia.[49]

While the term "test anxiety" refers specifically to students,[50] many workers share the same experience with regard to their career or profession. The fear of failing at a task and being negatively evaluated for failure can have a similarly negative effect on the adult.[citation needed] Management of test anxiety focuses on achieving relaxation and developing mechanisms to manage anxiety.[50]

Stranger and social[edit]

Humans generally require social acceptance and thus sometimes dread the disapproval of others. Apprehension of being judged by others may cause anxiety in social environments.[51]

Anxiety during social interactions, particularly between strangers, is common among young people. It may persist into adulthood and become social anxiety or social phobia. "Stranger anxiety" in small children is not considered a phobia. In adults, an excessive fear of other people is not a developmentally common stage; it is called social anxiety. According to Cutting,[52] social phobics do not fear the crowd but the fact that they may be judged negatively.

Social anxiety varies in degree and severity. For some people it is characterized by experiencing discomfort or awkwardness during physical social contact (e.g. embracing, shaking hands, etc.), while in other cases it can lead to a fear of interacting with unfamiliar people altogether. Those suffering from this condition may restrict their lifestyles to accommodate the anxiety, minimizing social interaction whenever possible. Social anxiety also forms a core aspect of certain personality disorders, including Avoidant Personality Disorder.[53]

Generalized[edit]

Overwhelming anxiety, if not treated early, can become a generalized anxiety disorder (GAD), identified by symptoms of exaggerated and excessive worry, chronic anxiety and constant, irrational thoughts. These anxious thoughts and feelings are difficult to control and can cause serious mental anguish that interferes with normal, daily functioning.[54]

The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) includes specific criteria for diagnosing generalized anxiety disorder. The DSM-IV states that a patient must experience chronic anxiety and excessive worry, almost daily, for at least 6 months from a number of stressors (such as work or school) and experience three or more defined symptoms, including, "restlessness or feeling keyed up or on edge, being easily fatigued, difficulty concentrating or mind going blank, irritability, muscle tension, sleep disturbance (difficulty falling or staying asleep, or restless unsatisfying sleep)".[55] Generalized anxiety disorder is more likely to be found among people who are living in a big city, or one that is politically and economically unstable.[56]

If symptoms of chronic anxiety are not addressed and treated in adolescence the risk of developing an anxiety disorder in adulthood increases.[57] "Clinical worry is also associated with risk of comorbidity with other anxiety disorders and depression" and thus immediate treatment is important.[57]

Generalized anxiety disorder can be treated through specialized therapies aimed at changing thinking patterns and in turn reducing anxiety-producing behaviors. Cognitive behavioral therapy (CBT) and short-term psychodynamic psychotherapy (STPP) can be used to treat GAD with positive effects lasting 12 months after treatment.[58] Other treatment plans can be used in conjunction with behavioral therapy to reduce the symptoms of generalized anxiety disorder.

According to Ghafoor, 90% of individuals suffering from a generalized anxiety disorder also struggle with at least one additional mental health issue. Of these individuals, up to 50% may have experienced a serious episode of depression by age 18. Mental health professionals in the field are thus asking more relevant questions of their patients to achieve more effective diagnoses. Ghafoor suggests that asking questions relating to personal symptoms (such as fatigue, irritability, or restlessness) offers a better a way for mental health professionals to create a more effective, personalized treatment plan.[59]

Trait[edit]

Anxiety can be either a short term 'state' or a long term "trait". Trait anxiety reflects a stable tendency to respond with state anxiety in the anticipation of threatening situations.[60] It is closely related to the personality trait of neuroticism. Such anxiety may be conscious or unconscious.[61]

Choice or decision[edit]

Anxiety induced by the need to choose between similar options is increasingly being recognized as a problem for individuals and for organizations.[62][63]

"Today we're all faced with greater choice, more competition and less time to consider our options or seek out the right advice."[64]

In a decision context, unpredictability or uncertainty may trigger emotional responses in anxious individuals that systematically alter decision-making.[65] There are primarily two forms of this anxiety type. The first form refers to a choice in which there are multiple potential outcomes with known or calculable probabilities. The second form refers to the uncertainty and ambiguity related to a decision context in which there are multiple possible outcomes with unknown probabilities.[65]

In some Buddhist meditation literature, this effect is described as something which arises naturally and should be turned toward and mindfully explored in order to gain insight into the nature of emotion, and more profoundly, the nature of self.[66]

Positive psychology[edit]

In positive psychology, anxiety is described as the mental state that results from a difficult challenge for which the subject has insufficient coping skills.[67]

Prevention[edit]

Several approaches to prevention of mental disorders in general are described in the article mental disorders. The use of treatments such as cognitive behavioral therapy (CBT) for people at risk for anxiety has been shown to significantly reduce the number of episodes of generalized anxiety disorder and anxiety symptoms. Through managing negative thoughts and maladaptive behavior, significant improvements in explanatory style, hopelessness, and dysfunctional attitudes are observed.[68][69][70]

Treatments[edit]

There are many ways to treat anxiety. Cognitive behavioral therapy and medication are two principal forms of anxiety treatment.[71] Stopping smoking has benefits in anxiety as large as or larger than those of medications.[72]

Cognitive behavioral therapy[edit]

The most notable treatment for anxiety is cognitive behavioral therapy (CBT).[73] Cognitive behavioral therapy involves the changing of one's thought by the therapist. Patients are asked to explain their feelings towards certain things or incidents that cause their anxious behavior.[74]

One study found that computerised CBT was equally effective as face-to-face CBT in adolescent anxiety.[75]

Herbal treatments[edit]

Traditional herbal remedies have been used for centuries to treat anxiety but many lack strong evidence of efficacy. There is some limited promising data supporting the use of kava and, to some extent, inositol, but the limited evidence available for St John's wort, valerian, and omega-3 fatty acids demonstrates little efficacy in anxiety and these remedies should not be recommended in place of more effective treatments.[76]

Caffeine elimination[edit]

For some people, anxiety may be reduced by eliminating caffeine consumption.[77] Anxiety can temporarily increase during caffeine withdrawal.[78][79][80]

Other treatments[edit]

Other methods used in treating anxiety include electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS), and psychosurgery. Psychosurgery is used in very extreme cases, when other treatment techniques do not work.[81] Evidence is insufficient regarding meditation to make any conclusions.[82]

See also[edit]

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