release of cortisol. in relation to anxiety, the amygdala activates this circuit, while the hippocampus is responsible for suppressing it. glucocorticoid receptors in the hippocampus monitor the amount of cortisol in the system and through negative feedback can tell the hypothalamus to stop releasing crh. studies on mice engineered to have high concentrations of crh showed higher levels of anxiety, while those engineered to have no or low amounts of crh receptors were less anxious. in people with phobias, therefore, high amounts of cortisol may be present, or there may be low levels of glucocorticoid receptors or even serotonin (5-ht). disruption by damage for the areas in the brain involved in emotion—most specifically fear— the processing and response to emotional stimuli can be altered when one of these regions is damaged. damage to the cortical areas involved in the limbic system, such as the cingulate cortex or frontal lobes, has resulted in extreme emotion changes. other types of damage include klüver–bucy syndrome and urbach–wiethe disease. in klüver–bucy syndrome, a temporal lobectomy, or removal of the temporal lobes, results in changes involving fear and aggression. specifically, the removal of these lobes results in decreased fear, confirming its role in fear recognition and response. damage to both side (bilateral damage) of the medial temporal lobes is known as urbach–wiethe disease. it presents with similar symptoms of decreased fear and aggression but with the addition of the inability to recognize emotional expressions, especially angry or fearful faces. the amygdala's role in learned fear includes interactions with other brain regions in the neural circuit of fear. while damage in the amygdala can inhibit its ability to recognize fearful stimuli, other areas such as the ventromedial prefrontal cortex and the basolateral nuclei of the amygdala can affect the region's ability to not only become conditioned to fearful stimuli but to extinguish them eventually. through receiving stimulus info, the basolateral nuclei undergo synaptic changes that allow the amygdala to develop a conditioned response to fearful stimuli. damage to this area, therefore, have been shown to disrupt the acquisition of learned responses to fear. likewise, damage in the ventromedial prefrontal cortex (the area responsible for monitoring the amygdala) has been shown to slow down the speed of extinguishing a learned fear response and how effective the extinction is. this suggests there is a pathway or circuit among the amygdala and nearby cortical areas that process emotional stimuli and influence emotional expression, all of which can be disrupted when damage occurs. diagnosis main articles: specific phobia, agoraphobia, and social anxiety disorder it is recommended that the terms distress and impairment take into account the context of the person's environment during diagnosis. the dsm-iv-tr states that if a feared stimulus, whether it be an object or a situation, is absent entirely in an environment, a diagnosis cannot be made. an example of this situation would be an individual who has a fear of mice but lives in an area without mice. even though the concept of mice causes marked distress and impairment within the individual, because the individual does not usually encounter mice, no actual distress or impairment is ever experienced. it is recommended that proximity to, and ability to escape from, the stimulus also be considered. as the phobic person approaches a feared stimulus, anxiety levels increase, and the degree to which the person perceives they might escape from the stimulus affects the intensity of fear in instances such as riding an elevator (e.g. anxiety increases at the midway point between floors and decreases when the floor is reached and the doors open). the dsm-v has been updated to reflect that an individual may have changed their daily activities around the feared stimulus in such a way that they may avoid it altogether. the person may still meet criteria for the diagnosis if they continue to avoid or refuse to participate in activities they would involve possible exposure to the phobic stimulus. specific phobia social anxiety disorder agoraphobia features fear out of proportion to the danger presented by an object or situation anxiety of social encounters due to potential scrutiny from others fear of leaving a protective place or situations viewed as being unable to escape from duration ≥ 6 months ≥ 6 months ≥ 6 months specific phobias a specific phobia is a marked and persistent fear of an object or situation. specific phobias may also include fear of losing control, panicking, and fainting from an encounter with the phobia. specific phobias are defined concerning objects or situations, whereas social phobias emphasize social fear and the evaluations that might accompany them. the dsm breaks specific phobias into five subtypes: animal, natural environment, blood-injection-injury, situational and other. in children, blood-injection-injury phobia, animal phobias, and natural environment phobias usually develop between the ages of 7 and 9 reflective of normal development. additionally, specific phobias are most prevalent in children between the ages 10 and 13. situational phobias are typically found in older children and adults. treatments there are various methods used to treat phobias. these methods include systematic desensitization, progressive relaxation, virtual reality, modeling, medication, and hypnotherapy. over the past several decades, psychologists and other researchers have developed effective behavioral, pharmacological, and technological interventions for the treatment of phobia. therapy cognitive behavioral therapy (cbt) can be beneficial by allowing the person to challenge dysfunctional thoughts or beliefs by being mindful of their feelings to recognize that their fear is irrational. cbt may occur in a group setting. gradual desensitization treatment and cbt are often successful, provided the person is willing to endure some discomfort. in one clinical trial, 90% of people no longer had a phobic reaction after successful cbt treatment. research in the uk has suggested that for childhood phobias a single session of cbt can be effective. evidence supports that eye movement desensitization and reprocessing (emdr) is effective in treating some phobias. its effectiveness in treating complex or trauma-related phobias has not been empirically established. primarily used to treat post-traumatic stress disorder, emdr has been demonstrated to ease phobia symptoms following a specific trauma, such as a fear of dogs following a dog bite. systematic desensitization a soldier stomping his foot to put out the fire rising up his leg during military fire-phobia training systematic desensitization is a process in which people seeking help slowly become accustomed to their phobia, and ultimately overcome it. traditional systematic desensitization involves a person being exposed to the object they are afraid of over time so that the fear and discomfort do not become overwhelming. this controlled exposure to the anxiety-provoking stimulus is key to the effectiveness of exposure therapy in the treatment of specific phobias. it has been shown that humor is an excellent alternative when traditional systematic desensitization is ineffective. humor systematic desensitization involves a series of treatment activities that elicit humor with the feared object. previously learned progressive muscle relaxation procedures can be used as the activities become more difficult. progressive muscle relaxation helps people relax before and during exposure to the feared stimulus. virtual reality therapy is another technique that helps phobic people confront a feared object. it uses virtual reality to generate scenes that may not have been possible or ethical in the physical world. it is equally as effective as traditional exposure therapy and offers additional advantages. these include controlling the scenes and having the phobic person endure more exposure than they might handle in reality. medications medications are a treatment option often utilized in combination with cbt or if cbt was not tolerated or effective. medications can help regulate apprehension and fear of a particular fearful object or situation. there are various medication options available for both social anxiety disorder and agoraphobia. the use of medications for specific phobias, besides the limited role of benzodiazepines, do not currently have established guidelines due to minimal supporting evidence. antidepressants antidepressant medications such as selective serotonin reuptake inhibitors (ssris), serotonin-norepinephrine reuptake inhibitors (snris), or monoamine oxidase inhibitors (maois) may be helpful in some cases. ssris / snris act on serotonin, a neurotransmitter in the brain. because of serotonins positive impacts mood, an antidepressant may be offered and prescribed as a treatment option. for social anxiety, the ssris sertraline, paroxetine, fluvoxamine, and the snri venlafaxine have fda approval. similar medications may be offered for agoraphobia. benzodiazepines sedatives such as benzodiazepines (clonazepam, alprazolam) are another therapeutic option, which can help people relax by reducing the amount of anxiety they feel. benzodiazepines may be useful in the acute treatment of severe symptoms, but the risk-benefit ratio usually goes against their long-term use in phobic disorders. this class of medication has recently been shown as effective if used with negative behaviours such as excessive alcohol use. despite this positive finding, benzodiazepines are used with caution due to side effects and risk of developing dependence or withdrawal symptoms. in specific phobia for example if the phobic stimulus is one that is not regularly encountered such as flying a short course may be provided. beta-blockers beta blockers (propranolol) are another therapeutic option, particularly for those with the performance only subtype of social anxiety disorder. they may stop the stimulating effects of adrenaline, such as sweating, increased heart rate, elevated blood pressure, tremors, and the feeling of a pounding heart. by taking beta-blockers before a phobic event, these symptoms are decreased, making the event less frightening. beta-blockers are not effective for generalized social anxiety disorder. hypnotherapy hypnotherapy can be used alone and in conjunction with systematic desensitization to treat phobias. through hypnotherapy, the underlying cause of the phobia may be uncovered. the phobia may be caused by a past event that the person does not remember, a phenomenon known as repression. the mind represses traumatic memories from the conscious mind until the person is ready to deal with them. hypnotherapy may also eliminate the conditioned responses that occur during different situations. people are first placed into a hypnotic trance, an extremely relaxed state in which the unconscious can be retrieved. this state makes people more open to suggestion, which helps bring about desired change. consciously addressing old memories helps individuals understand the event and see it less threateningly. prognosis outcomes vary widely among the phobic anxiety disorders. there is a possibility that remission occurs without intervention but relapses are common. response to treatment as well as remission and relapse rates are impacted by the severity of an individual's disorder as well as how long they have been experiencing symptoms. for example, in social anxiety disorder (social phobia) a majority of individuals will experience remission within the first couple of years of symptom onset without specific treatment. on the other hand, in agoraphobia as few as 10% of individuals are seen to reach complete remission without treatment. a study looking at the 2 year remission rates for anxiety disorders found that those with multiple anxieties were less likely to experience remission. specific phobia the majority of those that develop a specific phobia first experience symptoms in childhood. often individuals will experience symptoms periodically with periods of remission before complete remission occurs. however, specific phobias that continue into adulthood are likely to experience a more chronic course. specific phobias in older adults has been linked with a decrease in quality of life. those with specific phobias are at an increased risk of suicide. greater impairment is found in those that have multiple phobias. response to treatment is relatively high but many do not seek treatment due to lack of access, ability to avoid phobia, or unwilling to face feared object for repeated cbt sessions. comorbidities many of those with a phobia often have more than one phobia. there are also a number of psychological and physiological disorders that tend to occur or coexist at higher rates among this population. as with all anxiety disorders the most common psychiatric condition to occur with a phobia is major depressive disorder. additionally bipolar disorder, substance dependence disorder, obsessive-compulsive disorder, and post traumatic stress disorder have also been found to occur in those with phobias at higher rates. epidemiology phobias are a common form of anxiety disorder, and distributions are heterogeneous by age and gender. an american study by the national institute of mental health (nimh) found that between 8.7 percent and 18.1 percent of americans have phobias, making it the most common mental illness among women in