4th edition as of August 2026

Module Overview

In Module 9, we will discuss matters related to obsessive-compulsive and related disorders to include their clinical presentation, epidemiology, comorbidity, etiology, and treatment options. Our discussion will include obsessive compulsive disorder (OCD), body dysmorphic disorder (BDD), and hoarding.  Be sure you refer to Modules 1-3 for explanations of key terms (Module 1), an overview of the various models to explain psychopathology (Module 2), and descriptions of the therapies (Module 3).

 

Module Outline

• • 9.1. Clinical Presentation

• • 9.2. Epidemiology

• • 9.3. Comorbidity

• • 9.4. Etiology

• • 9.5. Treatment

 

Module Learning Outcomes

• Describe how obsessive-compulsive disorders present.
• Describe the epidemiology of obsessive-compulsive disorders.
• Describe comorbidity in relation to obsessive-compulsive disorders.
• Describe the etiology of obsessive-compulsive disorders.
• Describe treatment options for obsessive-compulsive disorders.

 

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9.1. Clinical Presentation

 

Section Learning Objectives

• Describe how obsessive-compulsive disorder presents.
• Describe how body dysmorphic disorder presents.
• Describe how hoarding disorder presents.

 

9.1.1. Obsessive-Compulsive Disorder

Obsessive-compulsive disorder, more commonly known as OCD, requires the presence of obsessions, compulsions, or both. Obsessions are defined as repetitive and persistent thoughts, urges, or images. These obsessions are intrusive, time-consuming (i.e., take more than an hour a day), and unwanted, often causing significant distress or impairment in an individual’s daily functioning. Common obsessions are contamination (dirt on self or objects), errors of uncertainty regarding daily behaviors (locking the door, turning off appliances), thoughts of physical harm or violence, and orderliness, to name a few (Cisler, Adams, et al., 2011; Yadin & Foa, 2009). Often the individual will try to ignore these thoughts, urges, or images. When they are unable to ignore them, the individual will engage in compulsory behaviors to gain temporary relief from the distress or anxiety.

Compulsions are time-consuming, repetitive behaviors or mental acts that an individual performs in response to an obsession. Common examples of compulsions are checking (e.g., repeatedly checking if the stove is turned off even though the first four-times they checked it was), counting (e.g., flicking the lights off and on exactly five times), hand washing, symmetry, fears of harm to self or others, or repeating specific words (APA, 2022). These compulsive behaviors essentially alleviate the anxiety associated with the obsessive thoughts. For example, an individual may feel as though their hands are dirty after using utensils at a restaurant. They may obsess over this thought for some time, impacting their ability to interact with others or complete a specific task. This obsession will ultimately lead to the individual performing a compulsion where they will wash their hands with extremely hot water to rid all the germs or even wash their hands a specified number of times if they also have a counting compulsion. At this point, the individual’s anxiety should be temporarily relieved.

These obsessions and compulsions are more excessive than the typical “cleanliness” as they consume a large part of the individual’s day. Additionally, they cause significant impairment in one’s daily functioning. Given the example above, an individual with a fear of contamination may refuse to eat at restaurants, or they may bring their utensils from home. The frequency and severity of the obsessions and compulsions varies by patient, with some having mild to moderate symptoms and only spending 1-3 hours a day obsessing or engaging in compulsive behaviors, while other patients present with severe symptoms and have nearly constant intrusive thoughts or compulsions that can become incapacitating (APA, 2022).

 

9.1.2. Body Dysmorphic Disorder

Body dysmorphic disorder is another obsessive disorder; however, the focus of the obsessions is with perceived defects or flaws in one’s physical appearance. A key feature of these obsessions is that they are not observable or appear slight to others. An individual who has a congenital facial defect or a burn victim who is concerned about their scars are not examples of an individual with body dysmorphic disorder. The obsessions related to one’s appearance can run the spectrum from feeling “unattractive” to “looking hideous.” While any part of the body can be a concern for an individual with body dysmorphic disorder, the most commonly reported areas are skin (acne, wrinkles, skin color), hair (particularly thinning or excessive body hair), and nose (size or shape; APA, 2022). Interestingly, the disorder can occur by proxy meaning the individual is not concerned with their own defects but those of another person, often a spouse or partner but at times, a parent, child, sibling, or stranger.

Due to the distressing nature of the obsessions regarding one’s body, individuals with body dysmorphic disorder also engage in compulsive behaviors that take up a considerable amount of time in their day. For example, they may repeatedly compare their body to other people’s bodies in the general public; frequently look at themselves in the mirror; engage in excessive grooming, which includes using make-up to modify their appearance. Some individuals with body dysmorphic disorder will go as far as having numerous plastic surgeries in attempts to obtain their “perfect” appearance.

While most of us are guilty of engaging in some of these behaviors, to meet criteria for body dysmorphic disorder, one must spend a considerable amount of time preoccupied with their appearance (i.e., on average 3-8 hours a day), as well as display significant impairment in social, occupational, or other areas of functioning. Some individuals excessively tan, change their clothes repeatedly, or compulsively shop such as for beauty products. Camouflaging perceived defects is a common behavior and could involve applying makeup, adjusting a hat or one’s clothes, or covering the forehead or eyes with one’s hair, all to hide or cover the perceived defect or problem area (APA, 2022).

As the DSM-5-TR notes, body dysmorphic disorder has been associated with, “abnormalities in emotion recognition, attention, and executive function, as well as information-processing biases and inaccuracies in interpretation of information and social situations” (APA, 2022, pg. 273). These individuals tend to express a bias for negative and threatening interpretations of facial expressions and situations that would be classified as ambiguous, for instance.

            9.1.2.1. Muscle dysmorphia. While muscle dysmorphia is not a formal diagnosis, it is a common type of BDD, particularly within the male population. Muscle dysmorphia refers to the belief that one’s body is too small or lacks the appropriate amount of muscle definition (Ahmed, Cook, Genen & Schwartz, 2014). While the severity of BDD between individuals with and without muscle dysmorphia appears to be the same, some studies have found higher use of substance abuse (i.e., steroid use), poorer quality of life, and increased reports of suicide attempts in those with muscle dysmorphia (Pope, Pope, Menard, Fay Olivardia, & Philips, 2005). The DSM-5-TR instructs clinicians to specify if body dysmorphic disorder occurs with muscle dysmorphia.

            9.1.2.2. Insight specifiers. Those diagnosed with body dysmorphic disorder vary in the degree of insight they have about the accuracy of their body dysmorphic disorder beliefs, ranging from good to absent/delusional. On average, insight is poor and at least one-third of those diagnosed with the disorder display absent/delusional insight. Mental health professionals would indicate the degree of insight regarding body dysmorphic disorder beliefs using with good or fair insight, with poor insight, or with absent insight/delusional beliefs. See page 272 of the DSM-5-TR for more information. Note that the insight specifier is used with OCD and hoarding disorders as well.

 

9.1.3. Hoarding Disorder

In hoarding disorder, the key feature is the persistent over-accumulation of possessions (APA, 2022). While we all obtain items throughout life, individuals with hoarding disorder continue to accumulate items without discarding possessions, regardless of their value or sentiment. This lack of discarding occurs over a long period and is not explained by a recent significant stressor (e.g., lost house in fire, so now keeps everything). For example, last week’s newspaper would likely have no relevance to you or possibly any historical value, but those with hoarding disorder would keep this newspaper despite the lack of value or sentiment.

The most commonly hoarded items are newspapers, magazines, clothes, bags, books, mail, and paperwork (APA, 2022). While these items may be stored in attics and garages, individuals with a hoarding disorder also have these items cluttering their living space, sometimes to the extent that they are unable to utilize their furniture because it is covered in stuff. Cognitive factors contributing to the need to hold onto these non-sentimental items are fear of losing valuable information and fear of being wasteful. When asked to “clean out” their house or get rid of these items, individuals with hoarding disorder experience significant distress. Individuals with hoarding disorder display indecisiveness, avoidance, procrastination, perfectionism, difficulty planning and organizing tasks, and are easily distractible.

One’s hoarding behaviors also impacts their daily functioning and causes impairment in social and occupational functioning. It can lead to low quality of life and in extreme cases, place the individual at risk for figure, falling, poor sanitation, and other health risks. Family relationships are often strained and conflict with neighbors and local authorities is common (APA, 2022).

 

 

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9.2. Epidemiology

 

Section Learning Objectives

• Describe the epidemiology of OCD.
• Describe the epidemiology of body dysmorphic disorder.
• Describe the epidemiology of hoarding disorder.

 

9.2.1. OCD

The prevalence rate for OCD is approximately 1.2% both in the U.S. and worldwide (APA, 2022). Women are diagnosed with OCD more often than males; however, in childhood, boys are diagnosed more frequently than girls (APA, 2022). With respect to gender and symptoms, females are more likely to be diagnosed with cleaning related obsessions and compulsions. In contrast, males are more likely to display symptoms related to forbidden thoughts and symmetry (APA, 2022). The DSM-5-TR reports that the mean age of onset of OCD is 19.5 years with a quarter of cases starting by 14 years of age. Additionally, males have an earlier age of onset (5-15 yrs.) compared to females (20-24 yrs.; Rasmussen & Eisen, 1990).

 

9.2.2. Body Dysmorphic Disorder

The point prevalence rate for body dysmorphic disorder among U.S. adults is 2.4% while outside the U.S., the point prevalence is 1.7% to 2.9%. Gender-based prevalence rates indicate that women are more likely to be diagnosed with body dysmorphic disorder than men, though muscle dysmorphia is diagnosed more frequently in men. Additionally, women are more likely to be preoccupied with weight, breasts, buttocks, legs, hips, and excessive body or facial hair while men have preoccupations with their genitals, body build, and thinning hair (APA, 2022).

 

9.2.3. Hoarding Disorder

While national studies on the prevalence rate of hoarding within the U.S. and internationally are not available, community surveys estimate clinically significant hoarding as occurring in 1.5% to 6.0% of the population (APA, 2022; Gilliam & Tolin, 2010). Clinical samples are more highly represented by females than males and older individuals (over the age of 65 years) are three times more likely to be diagnosed with hoarding disorder than younger adults.

 

 

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9.3. Comorbidity

 

Section Learning Objectives

• Describe the comorbidity of OCD.
• Describe the comorbidity of body dysmorphic disorder.
• Describe the comorbidity of hoarding disorder.

 

9.3.1. OCD

There is a high comorbidity between OCD and other anxiety disorders. Nearly 76% of individuals with OCD will be diagnosed with another anxiety disorder, most commonly panic disorder, social anxiety disorder, generalized anxiety disorder, or a specific phobia. Additionally, due to the nature of OCD and its symptoms, nearly 41% of those with OCD will also be diagnosed with a depressive or bipolar disorder (APA, 2022).

There is a high comorbidity between OCD and tic disorder, particularly in males with an onset of OCD in childhood. Children presenting with early-onset OCD typically have a different presentation of symptoms than traditional OCD. Research has also indicated a strong triad of OCD, tic disorder, and ADHD in children. Due to this psychological disorder triad, it is believed there is a neurobiological mechanism at fault for the development and maintenance of the disorders.

It should be noted that there are several disorders—schizophrenia, bipolar disorder, eating disorders, body dysmorphic disorder, and Tourette’s disorder – that OCD is much more common in. Therefore, clinicians who have a patient diagnosed with one of the disorders should also routinely assess patients for OCD (APA, 2022).

Finally, OCD has a mean rate of lifetime suicide attempts of 14.2%, a mean rate of lifetime suicidal ideation of 44.1%, and a mean rate of current suicidal ideation of 25.9%. Severity of OCD, the symptom dimension of unacceptable thoughts, a history of suicidality, and severity of comorbid depressive and anxiety symptoms are predictors of greater suicide risk (APA, 2022).

 

9.3.2. Body Dysmorphic Disorder

Major depressive disorder is the most common comorbid psychological disorder with body dysmorphic disorder and typically occurs after the onset of body dysmorphic disorder. Additionally, there are some reports of social anxiety disorder, OCD, and substance-related disorders (likely related to muscle enhancement; APA, 2022). Those with body dysmorphic disorder are four times more likely to have experienced suicidal thoughts and 2.6 times more likely to have made suicide attempts compared to healthy control subjects and those diagnosed with eating disorders, OCD, or any anxiety disorder.

 

9.3.3. Hoarding Disorder

Of those diagnosed with hoarding disorder, about 75% have a comorbid mood or anxiety disorder with major depressive disorder, social anxiety disorder, and generalized anxiety disorder being the most common comorbid conditions. Additionally, nearly 20% also meet the criteria for OCD (APA, 2022).

 

 

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9.4. Etiology

 

Section Learning Objectives

• Describe the biological causes of obsessive-compulsive disorders.
• Describe the cognitive causes of obsessive-compulsive disorders.
• Describe the behavioral causes of obsessive-compulsive disorders.

 

9.4.1. Biological

There are several biological explanations for obsessive-compulsive related disorders, including hereditary transmission, neurotransmitter deficits, and abnormal functioning in brain structures. Current research suggests that these disorders emerge through complex interactions between genetic factors, neurobiological processes, and environmental influences rather than from a single biological cause.

            9.4.1.1. Hereditary transmission. Research consistently supports a genetic contribution to OCD, with twin studies indicating heritability factors account for approximately 40-50% of the risk factors, although estimates may be even higher among individuals with childhood-onset OCD (Taylor, 2011). Monozygotic twins have a substantially greater concordance rate than dizygotic twins, supporting the genetic vulnerability; however, concordance rates are not 100% suggesting external factors also contribute to symptom development.

Family studies also support a genetic influence in OCD. First-degree relatives of individuals with OCD have an increased likelihood of developing OCD, with risks approximately 3 to 12 times higher than the public (Blanco-Vieira et al., 2023; Pauls et al., 2014).  Familial patterns appear particularly strong among individuals with early-onset OCD, suggesting that childhood onset may have a stronger genetic component than adult-onset OCD (Blanco-Vieria et al., 2023; Taylor, 2011).

Initial studies exploring genetic factors for BDD and hoarding also indicate a genetic influence; however, environmental factors appear to play a more significant role in the development of these disorders than that of OCD (Strom et al., 2022; Ahmed, et al., 2014).

            9.4.1.2. Neurotransmitters. Neurotransmitters, particularly serotonin, have been identified as a contributing factor to obsessive and compulsive behaviors. This discovery was made accidentally, when individuals with depression and comorbid OCD were given antidepressant medications clomipramine and fluoxetine—both of which increase levels of serotonin—to mediate symptoms of depression. Not only did these patients report a significant reduction in their depressive symptoms, but also a substantial improvement in their OCD symptoms (Bokor & Anderson, 2014). Antidepressant medications that do not affect serotonin levels are not effective in managing obsessive and compulsive symptoms, thus offering additional support for deficits of serotonin levels as an explanation of obsessive and compulsive behaviors (Sinopoli, Burton, Kronenberg, & Arnold, 2017; Bokor & Anderson, 2014).

Contemporary research suggests that OCD is not explained by a simple serotonin deficiency. Instead, OCD appears to involve complex interactions among multiple neurotransmitter systems, including glutamate, GABA, and dopamine (Marinova, Chuang, & Fineberg, 2017). More specifically, excessive glutamate activity may increase intrusive thoughts, reduced GABA may weaken the brain’s ability to inhibit “error” signals and altered dopamine activity may reinforce compulsive behaviors through habit and reward pathways (Jalal et al., 2023).

            9.4.1.3. Brain structures. Seeing as neurotransmitters have direct involvement in the development of obsessive-compulsive behaviors, it’s only logical that brain structures that house these neurotransmitters also likely play a role in symptom development. Neuroimaging studies implicate the brain structures and circuits in the frontal lobe, more specifically, the orbitofrontal cortex, which is located just above each eye (Marsh et al., 2014). This brain region is responsible for mediating strong emotional responses and converts them into behavioral responses. Once the orbitofrontal cortex receives sensory/emotional information via sensory inputs, it transmits this information through impulses. These impulses are then passed on to the caudate nuclei, which filters through the many impulses received, passing along only the strongest impulses to the thalamus. Once the impulses reach the thalamus, the individual essentially reassesses the emotional response and decides whether to act (Beucke et al., 2013). It is believed that individuals with obsessive compulsive behaviors experience overactivity of the orbitofrontal cortex and a lack of filtering in the caudate nuclei, thus causing too many impulses to transfer to the thalamus (Endrass et al., 2011). Further support for this theory has been shown when individuals with OCD experience brain damage to the orbitofrontal cortex or caudate nuclei and experience remission of OCD symptoms (Hofer et al., 2013).

 

9.4.2. Cognitive

Cognitive theorists believe that OCD behaviors occur due to an individual’s intrusive thoughts interpreted in maladaptive ways. Compulsive acts are then performed to calm the intrusive thoughts and anxiety. Common cognitive errors in individuals with OCD include heightened responsibility—the ability to predict and therefore, avert a situation; overemphasis on thought—thinking of an event increases the likelihood it will happen; controlling thoughts—full control over thoughts is essential; overestimation of threat—negative outcomes have a high likelihood of happening; perfectionism—actions have to be done exactly the right way, and intolerance of uncertainty—need to be fully assured that negative events will not happen (Abramowitz, 2006).

Within the cognitive model, disconfirmation bias—the tendency to focus on or search for evidence that a feared outcome has not been adequately prevented, rather than accepting evidence that everything is safe or complete—helps explain the persistence of obsessive thoughts. Individuals with OCD tend to dismiss or reinterpret evidence that contradicts their fears, thus preventing them from learning the feared outcome is unlikely to occur.

Cognitive inflexibility, or difficulty adapting one’s thinking or behavior when circumstances change, is another cognitive strategy seen in individuals with OCD. More specifically, individuals with OCD often struggle to shift attention away from obsessive thoughts, consider alternative explanations for their fears, or modify behaviors when new information indicates a feared outcome is unlikely. This reduced cognitive flexibility may contribute to rigid thinking patterns, repetitive behaviors, and persistent doubt making it difficult for individuals to disengage from compulsions (Jalal et al., 2023; Gruner & Pittenger, 2017).

Although intrusive thoughts occur frequently among individuals without OCD, most people can dismiss these thoughts or tolerate uncertainty without engaging in rituals. Individuals with OCD cannot dismiss these thoughts and attempt to neutralize distressing thoughts through compulsive behaviors or mental rituals. As you will see in more detail in the behavioral section below, these behaviors (compulsions) used to neutralize the thoughts (obsessions) provide temporary relief to the individual. As the individual is continually exposed to the obsession and repeatedly engages in the compulsive behaviors to neutralize their anxiety, the behavior is repeatedly reinforced, thus becoming a compulsion. This theory is supported by studies where individuals with OCD report using more neutralizing strategies and report significant reductions in anxiety after employing these neutralizing techniques (Jacob, Larson, & Storch, 2014; Salkovskis et al., 2003).

 

9.4.3. Behavioral

The behavioral explanation of obsessive compulsive-related disorders primarily focuses on the development and maintenance of compulsions rather than the origin of obsessions. Behaviorists believe that these compulsions begin with and are maintained through principles of operant conditioning, particularly negative reinforcement.  Individuals with OCD often experience intrusive, negative thoughts, images, or urges (obsessions) that produce anxiety, distress or sense of threat. To reduce this distress and prevent the feared outcome, individuals engage in compulsive behaviors or mental rituals.

Although compulsions may temporarily reduce anxiety, the short-term relief reinforces the behavior, making it more likely the individual will perform the compulsion again. Over time, this creates a cycle in which obsessions trigger distress, compulsions provide temporary relief, and the relief reinforces the compulsive behavior (Abramowitz et al., 2019).

More recent theories emphasize that compulsive behaviors can become habitual responses that are automatically triggered by obsessive thoughts or feelings of uncertainty. As these behaviors become more automatic, individuals may perform compulsions not only to reduce anxiety, but also because they experience a strong urge that the action must be completed in a particular way (Gillian, 2021). This theory may help to explain the persistent and repetitive nature of compulsions in OCD and why exposure and response prevention is such an effective treatment for OCD.

 

 

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9.5. Treatment

 

Section Learning Objectives

• Describe treatment options for OCD.
• Describe treatment options for body dysmorphic disorder.
• Describe treatment options for hoarding disorder.

 

9.5.1. OCD

            9.5.1.1. Exposure and Response Prevention (ERP). Treatment of OCD has come a long way in recent years. Exposure and Response Prevention (ERP) is considered the first-line psychological treatment for OCD and is among the most extensively researched behavioral intervention for anxiety-related disorders (APA, 2020; NICE, 2022). Originally developed by psychiatrist Victor Meyer (1966), ERP helps individuals gradually confront situations, thoughts, images, or urges that trigger obsessive fears while resisting the urge to engage in compulsive behaviors.

In ERP, individuals are intentionally exposed to an anxiety-provoking stimuli while refraining from engaging in their compulsion or other behaviors intended to reduce anxiety. Exposure sessions are often done in vivo (in real life), through imaginal exposure when the feared situations cannot be recreated safely, or through virtual or computer-based methods when needed. For example, an individual’s fear of accidently causing a house fire would be addressed through imaginal exposure, as this situation would not be safe or ethical.

Prior to beginning the exposure and response prevention exercises, the individual would develop an individualized hierarchy of feared situations, ranking them according to the level of distress they produce. Treatment typically begins with mildly challenging situations, progressing toward more difficult exposure as the individual becomes more confident in treatment. Rather than attempting to eliminate anxiety, ERP encourages the individual to tolerate the discomfort (Craske et al., 2014; Sewart & Craske, 2020). It is believed that ERP works by promoting inhibitory learning, in which individuals develop new learning that competes with obsessive fears rather than simply becoming accustomed to anxiety through repeated exposure. Over time, individuals learn they can experience uncertainty and distress without engaging in compulsions and the feared outcomes are unlikely to occur (Craske et al., 2014; Sewart & Craske, 2020). ERP is highly effective for many individuals with OCD. In fact, clinical trials suggest that approximately 60-70% of patients experience clinically significant improvement (Law & Boisseau, 2019; Stewart & Craske, 2020)

            9.5.1.2. Psychopharmacology. Medication alone generally produces moderate improvement in OCD symptoms, but relapse often occurs when treatment is discontinued. Among the most effective medications are those that inhibit the reuptake of serotonin, clomipramine and SSRIs. Reportedly, up to 60% of individuals experience clinically meaningful symptom improvement with these medications; however, many experience residual symptoms and relapse when medications are discontinued (NICE, 2022). While there has been some promise in a combined treatment option of exposure and response prevention and SSRIs, these findings were not superior to exposure and response prevention alone, suggesting that the inclusion of medication in treatment does not provide an added benefit (Foa et al., 2005). With that said, the use of medication may be beneficial for individuals who are unable or unwilling to participate in ERP, thus providing some symptom relief.

 

9.5.2. Body Dysmorphic Disorder (BDD)

Because there are strong similarities between OCD and BDD, it is not surprising that the treatments with the strongest support are similar. The first line of treatment for BDD is CBT that also incorporates ERP. Specific to BDD, individuals are gradually exposed to situations that trigger concerns about their perceived physical flaws while refraining from engaging in compulsive behaviors such as mirror checking, excessive grooming, skin picking, etc. Research has shown that CBT with ERP reduces BDD symptoms and improves psychosocial functioning (NICE, 2022; Wilhelm et al., 2014).

Pharmacological treatment is also effective for individuals with BDD. Like OCD, medications such as clomipramine and SSRIs have the strongest evidence of efficacy. These medications reduce obsessive thoughts, compulsive behaviors, anxiety and depressive symptoms associated with BDD. While these are effective in reducing body dysmorphic disorder symptoms, once medication is discontinued, symptoms resume nearly immediately suggesting this is not an effective long-term treatment option for those with body dysmorphic disorder (NICE, 2022; Phillips & Kelly, 2020).

Treatment outcomes for BDD are challenging due to the limited awareness and underdiagnosis and treatment of BDD. Limited insight into the psychological understanding of the disorder, as well as inherent barriers such as stigma of mental illness, likely contribute to seeking cosmetic versus psychological treatment (Schulte et al., 2020). Despite these barriers, recent research suggests that CBT treatment may be helpful in treating BDD. More specifically, Weingarden and colleagues (2021) found symptom remission in 68% of participants immediately following treatment, 52% reported sustained remission at 6-months. Furthermore, individuals achieving remission also reported significant improvement in depression severity, BDD-related insight, and quality of life.

            9.5.2.1. Plastic surgery and medical treatments. Individuals with BDD frequently seek cosmetic or dermatological procedures in effort to correct perceived physical deficits. Studies consistently show that cosmetic treatments rarely improve the underlying concerns. Consequently, individuals may request additional procedures or will shift their concerns to another body part (Phillips et al., 2001).  Given this, medical providers are encouraged to screen patients for BDD before performing elective cosmetic procedures.

 

9.5.3. Hoarding Disorder

Although hording disorder shares some features with OCD, research has demonstrated that many individuals with hoarding disorder do not experience intrusive thoughts, nor do they experience urges to perform rituals. Because of this difference, treatment for hoarding disorder has moved away from exposure and response prevention, and more toward a traditional cognitive-behavioral approach.

Frost and Hartl (1996) believed that individuals with hoarding disorder engage in complex decision-making processes, overanalyzing the value and worth of possessions, thus leading to hoarding the object as opposed to discarding it. Therefore, in addition to having the individual engage in exposure treatment, components of cognitive restructuring such as challenging maladaptive beliefs about possessions, skills training to improve organization and decision-making, as well as motivational interviewing strategies to increase readiness for change are typically added (Williams & Viscusi, 2016). Despite these effective strategies, hoarding disorder remains challenging to treat due to the limited insight into the severity of symptoms by most individuals. Research suggests that although CBT can lead to meaningful improvements, complete symptom remission is relatively uncommon (Mancebo, Eisen, Sibrava, Dyck, & Rasmussen, 2011).

 

 

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Module Recap

As in all modules past, we have discussed the clinical presentation, epidemiology, comorbidity, etiology, and treatment options for a specific class of disorders – obsessive compulsive and related disorders.

 

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End Module 9

4th edition as of August 2026