Introduction to Anxiety Disorders
Anxiety disorders involve extreme reactions to anxiety-inducing situations, including excessive worry, uneasiness, apprehension, or fear.
Summarize the general characteristics, etiology, and treatment of anxiety disorders
- Anxiety disorders are dysfunctional responses to anxiety-inducing situations. An anxiety disorder differs from normal anxiety in that it causes extreme distress and interferes with a person’s ability to lead a normal life.
- Humans’ hormonal anxiety response evolved to help us react to danger. However, anxiety becomes counterproductive and thus is deemed “disordered” when it is experienced with such intensity that it impedes social functioning.
- Anxiety disorders develop as the result of the interaction of genetic (inherited) and environmental factors.
- Low levels of GABA (a neurotransmitter in the brain that reduces central nervous system activity) can contribute to anxiety.
- Anxiety disorders can develop in response to life stresses such as financial worries or chronic physical illness.
- Treatment options for anxiety disorders include lifestyle changes, therapy, and medication. The most common intervention is cognitive behavioral therapy (CBT).
- anxiety: An unpleasant state of mental uneasiness, nervousness, apprehension, and concern about some event or situation.
- amygdala: The region of the brain, located in the medial temporal lobe, believed to play a key role in emotions such as fear and pleasure in both animals and humans.
- benzodiazepine: A psychoactive drug that is generally safe and effective in the short term, though cognitive impairments, aggression, or behavioral disinhibition occasionally occur.
Anxiety is a normal human emotion that everyone experiences from time to time. People may feel anxious when facing problems, challenges, changes, or difficult decisions. Anxiety disorders, however, are dysfunctional responses to anxiety-inducing situations. The difference between normal anxiety and an anxiety disorder is that anxiety disorders cause such severe distress as to interfere with someone’s ability to lead a normal life. “Anxiety disorder” refers to any of a number of specific disorders, including generalized anxiety disorder, phobia, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, and social anxiety disorder.
Anxiety disorders are defined by excessive worry, apprehension, and fear about future events or situations, either real or imagined. Specifically, symptoms may include:
- feelings of panic, fear, or uneasiness
- uncontrollable and obsessive thoughts
- flashbacks to traumatic events
- problems sleeping
- shortness of breath
- muscle tension
- heart palpitations
- dry mouth
- cold or sweaty hands
Anxiety disorders are diagnosed in between 4% and 10% of older adults; however, this figure is likely an underestimate of the true incidence due to the tendency of adults to minimize psychiatric problems and to focus on physical symptoms.
Anxiety in and of itself is not a bad thing. In fact, the hormonal response involved in anxiety evolved to help humans react to danger—it better prepares them to recognize threats and to act accordingly to ensure their safety. Such sensory information is processed by the amygdala, which communicates information about potential threats to the rest of the brain. However, anxiety becomes counterproductive and thus is deemed “disordered” when it is experienced with such intensity that it impedes social functioning.
Anxiety disorders develop as the result of the interaction of genetic (inherited) and environmental factors. Neurologically speaking, increased amygdala reactivity is correlated with increased fear and anxiety responses. Low levels of GABA (a neurotransmitter in the brain that reduces central nervous system activity) can contribute to anxiety, and serotonin, glutamate, and the 5-Ht2A receptor have also all been implicated in the development of anxiety disorders.
In addition to biological factors, anxiety disorders can also be caused by various life stresses, such as financial worries or chronic physical illness. Severe anxiety and depression can also be induced by sustained alcohol abuse; with prolonged sobriety these symptoms usually decrease. Even moderate sustained alcohol use may increase anxiety and depression levels in some individuals. Caffeine, alcohol, and benzodiazepine dependence can worsen or cause anxiety and panic attacks.
Treatment options for anxiety disorders include lifestyle changes, therapy, and medication. The most common intervention is cognitive behavioral therapy (CBT), which aims to help the person identify and challenge their negative thoughts (cognitions) and change their reactions to anxiety-provoking situations (behaviors).
In terms of medication, SSRIs are most commonly recommended. Benzodiazepines are also sometimes indicated for short-term or “as-needed” use. MAOIs such as phenelzine and tranylcypromine are also considered effective and are especially useful in treatment-resistant cases, but dietary restrictions and medical interactions may limit their use.
Generalized Anxiety Disorder
Generalized anxiety disorder is characterized by chronic anxiety that is excessive, uncontrollable, and often irrational.
Summarize the diagnostic criteria, etiology, and treatment of generalized anxiety disorder
- Generalized anxiety disorder (GAD) is characterized by chronic anxiety that is excessive, uncontrollable, often irrational, and disproportionate to the actual object of concern.
- In order to be diagnosed with GAD, a person must experience excessive anxiety about a variety of events or activities for at least 6 months, and this excessive worry must interfere with some aspect of their daily social or occupational functioning.
- Although there has been little research investigating the heritability of GAD, a summary of available family and twin studies suggests that genetic factors play a moderate role in development of this disorder.
- Cognitive theories of GAD suggest that worry represents a mental strategy to avoid more powerful negative emotions (Aikins & Craske, 2001), perhaps as a result of earlier unpleasant or traumatic experiences.
- Treatment for GAD includes medication (such as SSRIs ) and various forms of psychotherapy (such as cognitive behavioral therapy).
- serotonin: An indoleamine neurotransmitter (5-hydroxytryptamine) that is involved in depression and that is crucial in maintaining a sense of well-being and security.
- comorbidity: The presence of one or more disorders (or diseases) in addition to a primary disorder or disease.
Defining Generalized Anxiety Disorder
Generalized anxiety disorder (GAD) is characterized by chronic anxiety that is excessive, uncontrollable, often irrational, and disproportionate to the actual object of concern. People with GAD often characterize it as a feeling of “free-floating anxiety”—a term that Sigmund Freud used in his early work. Typically, the anxiety has no definite trigger or starting point, and as soon as the individual resolves one issue or source of worry another worry arises. People with GAD also tend to catastrophize, meaning they may assume the absolute worst in anxiety-inducing situations. Racing thoughts, inability to concentrate, and inability to focus are also characteristic of GAD.
GAD is a particularly difficult disorder to live with; because the individual’s anxiety is not tied to a specific situation or event, they experience little relief. This disorder can contribute to problems with sleep, work, and daily responsibilities and often impacts close relationships.
DSM-5 Diagnostic Criteria
In order for GAD to be diagnosed, a person must experience excessive anxiety and worry—more days than not—for at least 6 months and about a number of events or activities (such as work or school performance). This excessive worry must interfere with some aspect of life, such as social, occupational, or daily functioning, and the person must have trouble controlling the anxiety. The disturbance must not be attributed to the physiological effects of a substance (e.g., a drug or medication) or another medical condition, and must not be better explained by another medical disorder. At least 3 of the following symptoms must be experienced: restlessness or feeling keyed up or on edge; being easily fatigued; difficulty concentrating or mind going blank; irritability; muscle tension; and/or sleep disturbance.
In any given year, approximately 2.3% of American adults and 2% of European adults experience GAD. Although there have been few investigations into the disorder’s heritability, a summary of available family and twin studies suggests that genetic factors play a moderate role in its development (Hettema et al., 2001). Specifically, about 30% of the variance for generalized anxiety disorder can been attributed to genes. Individuals with a genetic predisposition for GAD are more likely to develop the disorder, especially in response to a life stressor.
Cognitive theories of GAD suggest that worry represents a mental strategy to avoid more powerful negative emotions (Aikins & Craske, 2001), perhaps stemming from earlier unpleasant or traumatic experiences. Indeed, one longitudinal study found that childhood maltreatment was strongly related to the development of this disorder during adulthood (Moffitt et al., 2007). According to these theories, generalized anxiety may serve as a distraction from remembering painful childhood experiences.
Long-term use of benzodiazepines can worsen underlying anxiety, with evidence that reduction in benzodiazepine use can in turn lead to a lessening of anxiety symptoms. Similarly, long-term alcohol use is associated with the development of anxiety disorders, with evidence that prolonged abstinence can in turn result in the remission of anxiety symptoms.
GAD is generally chronic, but it can be managed, or even eliminated, with the proper treatment. While there are many options for treating GAD, full recovery is only seen about 50% of the time, which indicates the need for further research into more effective treatment options.
Pharmaceutical treatments for GAD include selective serotonin reuptake inhibitors (SSRIs), which are more commonly used as antidepressants. SSRIs block the reabsorption of serotonin in the brain so that it can keep activating serotonin receptors, improving the individual’s mood.
Two popular therapeutic programs used for treating GAD are applied relaxation, which focuses on muscle-relaxation techniques, and cognitive behavioral therapy (CBT), which focuses on ways to recognize and reduce worried thoughts. In a study comparing the two, it was found that CBT produced better post-treatment results. Other forms of therapy found to be effective in treating GAD include metacognitive therapy (MCT), which treats the “worrying about worrying” (or “meta-worrying”) often found in GAD, and intolerance-of-uncertainty (IUT), which focuses on resolving people’s difficulty dealing with uncertain situations. A particular challenge in treating GAD is its high comorbidity with other disorders, such as depression and substance abuse; it can be difficult in therapy to make progress with multiple issues simultaneously.
Panic Disorder and Panic Attacks
A panic attack is a sudden period of intense anxiety; if these attacks occur often, they may indicate a panic disorder.
Summarize the diagnostic criteria, etiology, and treatment of panic disorder
- A panic attack is a period of extreme fear or discomfort that develops abruptly and reaches a peak within 10 minutes. Its symptoms can include accelerated heart rate, sweating, trembling, choking sensations, and/or dizziness.
- People with panic disorder experience recurrent ( more than one) and unexpected panic attacks, along with at least one month of persistent concern about additional panic attacks.
- People with panic disorder may become so afraid of having panic attacks that they experience what are known as anticipatory attacks—essentially living in fear of fear.
- Family and twins studies indicate that the heritability of panic disorder is around 43%. Neurobiological theories suggest that a region of the brain called the locus coeruleus may play a role in this disorder.
- Conditioning theories propose that panic attacks are classical conditioning responses; similarly, cognitive theories argue that those with panic disorder are prone to interpret ordinary bodily sensations catastrophically.
- Although there is no known cure, panic disorder can be successfully treated in many cases using psychotherapy, medication, or a combination of both.
- agoraphobia: The fear of wide open spaces, crowds, or uncontrolled social conditions.
- panic attack: A sudden period of intense anxiety, mounting physiological arousal, fear, stomach problems, and discomfort that are associated with a variety of somatic and cognitive symptoms.
- comorbidity: The presence of one or more disorders or diseases in addition to a primary disorder or disease.
A panic attack is defined as a period of extreme fear or discomfort that develops abruptly and reaches a peak within 10 minutes. Its symptoms include accelerated heart rate, sweating, trembling, choking sensations, hot flashes or chills, dizziness or lightheadedness, fears of losing control or going crazy, and fears of dying (APA, 2013). Sometimes panic attacks are expected, occurring in response to specific environmental triggers (such as being in a tunnel); other times, these episodes are unexpected and emerge randomly (such as when relaxing).
People with panic disorder experience recurrent (more than one) and unexpected panic attacks, along with at least one month of persistent concern about additional panic attacks, worry over the consequences of the attacks, or self-defeating changes in behavior related to the attacks (such as withdrawing from social activities out of fear of having an attack) (APA, 2013). Since panic attacks can occur unexpectedly, they can become a cause of ongoing worry and avoidance. People with panic disorder may become so afraid of having panic attacks that they experience what are known as anticipatory attacks—essentially panicking about potential panic attacks and entering a cycle of living in fear of fear.
Panic disorder is very treatable; however, left untreated, it can significantly reduce quality of life. People with untreated panic disorder are at an increased risk for specific phobias, such as agoraphobia (a fear of leaving the house), and they often suffer from one or more additional mental-health conditions, such as depression or substance abuse.
DSM-5 Diagnostic Criteria
In the DSM-5, panic attacks themselves are not mental disorders; instead, they are listed as specifiers for other mental disorders, such as anxiety disorders. Panic attacks are differentiated as being either expected or unexpected; the categories from the previous DSM-IV-TR (situationally bound/cued, situationally predisposed, or unexpected/uncued) have been removed.
In order to be diagnosed with panic disorder, a person must experience unexpected, recurrent panic attacks. These panic attacks must also be accompanied by at least one month of a significant and related behavior change in relation to the attacks, a persistent concern or fear of more attacks, or a worry about the attacks’ consequences. As is the case with other anxiety disorders, the panic attacks cannot result from the physiological effects of drugs and other substances, a medical condition, or another mental disorder. While the previous version of the DSM defined panic disorder as occurring either with or without agoraphobia, the new DSM-5 lists panic disorder and agoraphobia as two distinct disorders.
Both genetic and environmental causes (often in combination) can cause panic disorder. Children are at a higher risk of developing panic disorder if their parents have the disorder (Biederman et al., 2001), and family and twins studies indicate that the heritability of panic disorder is around 43% (Hettema, Neale, & Kendler, 2001). The exact genes and gene functions involved in this disorder, however, are not well understood (APA, 2013). Neurobiological theories of panic disorder suggest that a region of the brain called the locus coeruleus may play a role in this disorder. Located in the brainstem, the locus coeruleus is the brain’s major source of norepinephrine, a neurotransmitter that triggers the body’s fight-or-flight response. Activation of the locus coeruleus is associated with anxiety and fear, and research with nonhuman primates has shown that stimulating the locus coeruleus either electrically or through drugs produces panic-like symptoms (Charney et al., 1990). Such findings have led to the theory that panic disorder may be caused by abnormal norepinephrine activity in the locus coeruleus (Bremner, Krystal, Southwick, & Charney, 1996).
Although the genetic link is clear, 75% of those diagnosed with panic disorder do not have a close relative with the disorder—indicating the significance of environmental factors. Major life changes (such as moving out of the family home, getting married, starting a new job, or having a baby) often precede the onset of panic disorder by contributing to stress.
Conditioning theories of panic disorder propose that panic attacks are classical-conditioning responses to subtle bodily sensations resembling those normally occurring when one is anxious or frightened (Bouton, Mineka, & Barlow, 2001). For example, consider a child who has asthma. An acute asthma attack produces sensations, such as shortness of breath, coughing, and chest tightness, that typically elicit fear and anxiety. Later, when the child experiences subtle symptoms that resemble the frightening symptoms of earlier asthma attacks (such as shortness of breath after climbing stairs), he may become anxious, fearful, and then experience a panic attack. Similarly, cognitive theories (Clark, 1996) argue that those with panic disorder are prone to interpret ordinary bodily sensations catastrophically, and these fearful interpretations set the stage for panic attacks.
Although there is no known cure, panic disorder can be successfully treated in many cases using psychotherapy, medication, or a combination of both. Cognitive behavioral therapy (CBT) is the psychotherapeutic treatment of choice for panic disorder; several studies show that 85 to 90 percent of panic-disorder patients treated with CBT recover completely from their panic attacks within 12 weeks. The goal of cognitive behavioral therapy is to help a patient reorganize thinking processes and anxious thoughts regarding an experience that provokes panic. Psychotherapy can improve the effectiveness of medication, reduce the likelihood of relapse for someone who has discontinued medication, and offer help for people with panic disorder who do not respond at all to medication. Selective serotonin reuptake inhibitors (SSRIs) are first-line medication treatments for panic disorder; they are preferred over benzodiazapines due to concerns about the latter regarding tolerance, dependence, and abuse.
Social Anxiety Disorder (Social Phobia)
Social anxiety disorder is marked by intense fear and avoidance of social situations in which one might be negatively judged.
Summarize the diagnostic criteria, etiology, and treatment of social phobia
- Social anxiety disorder (formerly called social phobia ) is characterized by extreme and persistent fear or anxiety and avoidance of social situations in which the person could potentially be evaluated negatively by others.
- Physical symptoms often accompanying social anxiety disorder include excessive blushing, excessive sweating, trembling, heart palpitations, nausea, stammering, rapid speech, and panic attacks.
- A person with social anxiety disorder experiences an intense fear of social situations, marked specifically by the fear of embarrassment or humiliation. This anxiety causes considerable distress in at least some parts of social, occupational, academic, or daily life.
- Research into the causes of social anxiety and social phobia is wide-ranging, encompassing multiple perspectives including neuroscience, genetics, conditioning, and social factors such as bullying.
- The first-line treatment for social anxiety disorder is cognitive behavioral therapy (CBT), which seeks to change thought patterns and physical reactions to anxiety-inducing situations.
- phobia: Fear of a specific thing.
- inhibition: A personal feeling of fear or embarrassment that stops one from behaving naturally.
- conditioning: The process of modifying a person’s or an animal’s behavior.
Defining Social Anxiety
Social anxiety disorder (formerly called social phobia) is characterized by extreme and persistent fear or anxiety and avoidance of social situations in which the person could potentially be evaluated negatively by others (APA, 2013). As with specific phobias, social anxiety disorder is common in the United States; a little over 12% of all Americans experience social anxiety disorder during their lifetime (Kessler et al., 2005).
The heart of the anxiety in social anxiety disorder is the person’s concern that they may act in a humiliating or embarrassing way, such as appearing foolish, showing symptoms of anxiety (such as blushing), or doing or saying something that might lead to rejection (such as offending others). The kinds of social situations that may cause distress include public speaking, having a conversation, meeting strangers, eating in restaurants, or using public restrooms. Although many people become anxious in social situations like public speaking, the fear, anxiety, and avoidance experienced in social anxiety disorder are highly distressing and lead to serious impairments in life.
Physical symptoms often accompanying social anxiety disorder include excessive blushing, excessive sweating, trembling, palpitations, and nausea. Stammering may be present, along with rapid speech. Panic attacks can also occur under intense fear and discomfort. Some sufferers may use alcohol or other drugs to reduce fears and inhibitions at social events. Adults with this disorder are more likely to experience lower educational attainment and lower earnings (Katzelnick et al., 2001); more likely to perform poorly at work and to be unemployed (Moitra, Beard, Weisberg, & Keller, 2011); and report greater dissatisfaction with their family lives, friends, leisure activities, and income (Stein & Kean, 2000).
When people with social anxiety disorder are unable to avoid situations that provoke anxiety, they typically perform safety behaviors: mental or behavioral acts that reduce anxiety in social situations by reducing the chance of negative social outcomes. Safety behaviors can include avoiding eye contact, rehearsing sentences before speaking, talking only briefly, and not talking about oneself (Alden & Bieling, 1998). Although these behaviors are intended to prevent the person with social anxiety disorder from doing something awkward that might draw criticism, these actions often exacerbate the problem because they do not allow the individual to disconfirm their negative beliefs, often eliciting rejection and other negative reactions from others (Alden & Bieling, 1998).
DSM-5 Diagnostic Criteria
In order to be diagnosed with social anxiety disorder, a person must experience an intense fear in one or more social situations, marked specifically by the fear of embarrassment or humiliation. This anxiety—or efforts to avoid the anxiety-inducing situation—must cause considerable distress and an impaired ability to function in at least some parts of social, occupational, academic, or daily life. Symptoms must last at least six months in order for a diagnosis to occur, and the symptoms must not be better accounted for by the effects of substance use, a medical condition, or another mental illness.
Research into the causes of social anxiety and social phobia is wide-ranging, encompassing multiple perspectives from neuroscience to sociology. Scientists have yet to pinpoint the exact causes. Studies suggest that genetics can play a part in combination with environmental factors. It has been shown that there is a two- to threefold greater risk of having social phobia if a first-degree relative also has the disorder; this could be due to genetics and/or due to children acquiring social fears and avoidance through observational learning.
As with specific phobias, it is highly probable that the fears inherent in social anxiety disorder can develop through conditioning experiences. For example, children who are subjected to early unpleasant social experiences (e.g., bullying at school) may develop negative social images of themselves that become activated later in anxiety-provoking situations (Hackmann, Clark, & McManus, 2000). Indeed, one study reported that 92% of a sample of adults with social anxiety disorder reported a history of severe teasing in childhood, compared to only 35% of a sample of adults with panic disorder (McCabe, Antony, Summerfeldt, Liss, & Swinson, 2003).
One of the most well-established risk factors for developing social anxiety disorder is behavioral inhibition (Clauss & Blackford, 2012). Behavioral inhibition is thought to be an inherited trait, and it is characterized by a consistent tendency to show fear and restraint when presented with unfamiliar people or situations (Kagan, Reznick, & Snidman, 1988). A recent statistical review of studies demonstrated that behavioral inhibition was associated with a greater-than sevenfold increase in the risk of development of social anxiety disorder, indicating that behavioral inhibition is a major risk factor for the disorder (Clauss & Blackford, 2012).
The first-line treatment for social anxiety disorder is cognitive behavioral therapy (CBT), which has been shown to be effective in treating social phobias through both individual and group therapy. The cognitive and behavioral components seek to change thought patterns and physical reactions to anxiety-inducing situations.
The attention given to social anxiety disorder has significantly increased since 1999, with the approval and marketing of several drugs for its treatment. Prescribed medications include several classes of antidepressants: selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and monoamine oxidase inhibitors (MAOIs). Other commonly used medications include beta blockers and benzodiazepines.
Specific phobias involve excessive, distressing, and persistent fear or anxiety about a specific object or situation.
Summarize the diagnostic criteria, etiology, treatment, and most common categories of specific phobias
- A specific phobia is an intense fear of a specific object or situation, such as snakes, heights, or flying. Between 5% and 12% of the population worldwide suffer from phobic disorders, making it the single largest category of anxiety disorders.
- There are five categories of phobias: environment phobias, animal phobias, blood-injury phobias, situational phobias, and other phobias not otherwise specified.
- When confronted with the object of their phobia, a person will generally enter a state of panic and experience a wide variety of physical symptoms, such as nausea, increased heartbeat, dizziness, and sweaty palms.
- Researchers in evolutionary medicine believe that phobias are adaptive, as they allow humans to recognize a potential threat and to act accordingly in order to ensure safety.
- There are various methods used to treat phobias, such as systematic desensitization, virtual reality therapy, cognitive behavioral therapy, eye-movement desensitization and reprocessing, hypnosis, and medication.
- agoraphobia: The fear of wide open spaces, crowds, or uncontrolled social conditions.
- panic: Overpowering fright, often affecting groups of people or animals.
A person diagnosed with a specific phobia (formerly known as a “simple phobia”) experiences excessive, distressing, and persistent fear or anxiety about a specific object or situation (such as animals, enclosed spaces, elevators, or flying) (APA, 2013). Even though people realize their level of fear and anxiety in relation to the phobic stimulus is irrational, some people with a specific phobia may go to great lengths to avoid the phobic stimulus (the object or situation that triggers the fear and anxiety). Typically, the fear and anxiety a phobic stimulus elicits is disruptive to the person’s life. For example, a man with a phobia of flying might refuse to accept a job that requires frequent air travel, thus negatively affecting his career. Between 5% and 12% of the population worldwide suffer from phobic disorders, making it the single largest category of anxiety disorders.
When confronted with the object of their phobia, a person will generally enter a state of panic and experience a wide variety of physical symptoms, such as nausea, increased heartbeat, dizziness, and sweaty palms. For this reason, many people with phobias simply avoid the object of their phobia. Such avoidance can range from not wanting to be outside in a lightning storm to being unable to even look at a picture of lightning.
There are five general categories of phobias:
- Environment phobias (e.g., fear of lightning, fear of tornadoes)
- Animal phobias (e.g., fear of snakes, fear of bears)
- Blood-injury phobias, (e.g., fear of getting a shot, fear of the sight of blood)
- Situational phobias (e.g., fear of heights, fear of public speaking)
- Other phobias not otherwise specified (e.g., fear of vomiting)
DSM-5 Diagnostic Criteria
In order to be diagnosed with a specific phobia, a person must experience a marked and persistent fear that is excessive or unreasonable, cued by the presence or anticipation of a specific object or situation (e.g., flying, heights, animals, receiving an injection, seeing blood). These symptoms must last for at least six months. Exposure to the object of the phobia nearly always elicits extremely distressing symptoms of anxiety, either immediately (“situationally bound”) or after some time delay (“situationally predisposed”). The person either avoids the phobic situation(s) or else endures it with extreme distress.
The avoidance and/or distress associated with the phobia must interfere significantly with the person’s academic or social functioning. Like all anxiety disorders, the symptoms must not be better accounted for by another mental disorder or by substance use.
At a low level, fear and anxiety are not bad things. In fact, the hormonal response to anxiety has evolved as a benefit, since it helps humans react to dangers. Researchers in evolutionary medicine believe this adaptation allows humans to recognize a potential threat and act accordingly in order to ensure safety.
The fact that specific phobias tend to be directed disproportionately at certain objects (such as snakes and spiders) may have evolutionary explanations as well. In this view, phobias are adaptations that may have been useful in the ancestral environment. On the savanna, dangers such as large predators, snakes, and spiders tend to be hidden from view until very close and may be a particular danger to infants and small children, favoring the development of an instinctive fearful response. Agoraphobia (fear of open spaces) may have been advantageous to our ancestors if it compelled them to avoid large open spaces without cover or concealment where they could be harmed. Thus, there may be a genetic predisposition to learn to fear certain things more easily than others.
Though the specific cause of phobias is unknown, they could be inherited; research has shown that if a person has a family member with a phobia, they are more likely to have one themselves. Phobias can also develop because of certain circumstances or occurrences, such as having been bitten by a snake, having seen someone else be bitten by a snake, having witnessed someone else being afraid of snakes, or having learned about someone being bitten by snake.
There are various methods used to treat phobias. Systematic desensitization is a process in which patients seeking help slowly become accustomed to their phobia, and ultimately overcome it. Similar to this, virtual reality therapy helps patients imagine encounters with the phobic object by simulating scenes that may not be possible or easy to find in the physical world. Cognitive behavioral therapy (CBT) allows the patient to challenge dysfunctional thoughts or beliefs by being mindful of their own feelings, with the aim that the patient will realize that their fear is irrational. Mainly used to treat post-traumatic stress disorder, eye-movement desensitization and reprocessing (EMDR) has been demonstrated as effective in easing phobia symptoms following a specific trauma, such as a fear of dogs following a dog bite. Hypnotherapy can be used alone and in conjunction with systematic desensitization to treat phobias. Finally, antidepressant medications such as SSRIs or MAOIs may be helpful in some cases of phobia.