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Understanding the Relationship Between Autism, OCD, and Repetitive Behaviors

One of the long-standing challenges in supporting individuals with Autism Spectrum Disorders (ASD) is the high rate of repetitive behavior they demonstrate. In addition to these individuals demonstrating high rates of repetitive behavior, many caregivers and support providers find it difficult to reduce the frequency or severity of impact these behaviors have on adaptive functioning and participation in community-based programs and activities. Part of this difficulty could potentially be related to complications that derive from the fact that repetitive behavior also is a central symptom of Obsessive Compulsive Disorder (OCD) and a variety of other neurodevelopmental disorders. This might be resulting in many treatment and support teams being confused about the nature of the repetitive behavior, and as a result, failing to use the most appropriate strategies to address those concerns. Our focus for this article will be to provide an outline of these initial concerns and offer some general insights into better understanding the relationship between ASD and OCD.

Philip Smith, PhD

Philip Smith, PhD

Unfortunately, in many applied settings, practitioners and caregivers often refer to the repetitive behavior of individuals with ASD as “that is just their OCD.” This is problematic since it reflects a misunderstanding of the nature of OCD and its relationship to ASD. Both are disorders which have diagnostic criteria and appropriate treatment and/or support strategies. Sometimes, repetitive behavior may be the result of another neurodevelopmental disability, such as Intellectual Disability. In many cases these behaviors reflect the impact of ASD and have nothing to do with OCD, while for other individuals the behavior may result from OCD and have nothing to do with ASD. Finally, for some individuals, ASD and OCD may co-occur, and some instances of repetitive behavior may be due to one disorder while other instances behaviors are caused by the other disorder. It is also possible that some behaviors may be impacted by the interaction of these disorders, but that discussion goes beyond the scope of this article.

The best current understanding of the repetitive behaviors that are seen in ASD and OCD, is that they typically occur for different reasons and call for differing treatment approaches. For example, many environmental accommodations for youth with ASD seek to find ways to make the repetitive behavior less stigmatizing or less disruptive, even though the repetition is not eliminated. This may include teaching a youth to follow a visual schedule, which actually involves substituting a repetitive behavior that is adaptive and may reduce anxiety or uncertainty, for one that is maladaptive and potentially disruptive. In contrast, the treatment goal for patients with OCD is to teach them to identify and eliminate obsessive thoughts and to completely block compulsive or repetitive behaviors. Failure to take the correct approach could be one reason that caregivers and support providers have had trouble addressing specific patterns of repetitive behavior for the individuals they are supporting. This makes differential diagnosis and/or diagnosis of co-occurring disorders an especially important process.

In order to understand this challenge, we need to begin with the recognition that some degree of repetitive behavior is normal and adaptive. In other words, not all repetitive behavior is pathological. Repetition of behavior is seen in a variety of everyday circumstances, including: childhood rituals associated with magical beliefs and fears, things people do in under-stimulating environments, greeting rituals, and a variety of behaviors associated with social situations such as club activities, establishing dominance or preparing for recurring events, as well as daily routines or habits. In many cases, these behaviors serve a valuable adaptive purpose. This highlights the need to determine how much, and what type of repetition in behavior should be recognized as pathological. Establishing a systematic basis for these decisions is the purpose of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (American Psychiatric Association, 2013).

Along with a continuum of normal through pathological repetitive behavior, it also should be noted that repetitive behavior is commonly observed in individuals with a number of other psychiatric disorders including the Schizophrenia spectrum and a number of anxiety disorders. Within the neurodevelopmental disorders chapter, elevated rates of repetitive behavior are observed in a variety of Intellectual and Developmental Disabilities, not just ASD (Bodfish, et al, 2000). Research has shown, however, that a higher percentage of individuals with ASD demonstrate problematic patterns of repetitive behavior, and that these repetitive behaviors show a wider variety of pattern and motivation, based on behavioral analysis (Bodfish, et al, 2000).

At this point it makes sense to consider a brief overview of the diagnostic criteria for the disorders we are considering. ASD symptoms are broken down into two categories: persistent deficits in social communication and social interaction across multiple contexts, and restricted, repetitive patterns of behavior, interests, or activities, which is the focal point of this discussion. Examples of these include: stereotyped or repetitive motor movements, use of objects, or speech (e.g., simple motor stereotypies, lining up toys or flipping objects, echolalia, idiosyncratic phrases), insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behavior (e.g., extreme distress at small changes, difficulties with transitions, rigid thinking patterns, greeting rituals, need to take same route every day).

While we don’t know the exact cause(s) of ASD, it is recognized as a neurodevelopmental disorder, and the general understanding of many of the repetitive behaviors attributed to ASD is that they are the result of some type of neurological irregularity. Many of these behaviors are interpreted as attempts to cope with sensory factors, and others may relate to cognitive difficulties secondary to those neurological factors. A variety of explanations have been suggested, including: attempts to compensate for hyposensitivity or hypersensitivity to sensory stimuli, regulating the nervous system and its response to these stimuli, and/or attempting to provide increased understanding of cause and effect relationships or anticipating what is likely to happen next. Using repetitive behavior in this way might be compared to the reasons people fidget when they are bored or repeating something to oneself in order to remember it. The difference is that the repetition reaches a level that undermines adaptive functioning or disrupts the environment in which the individual is living. This may be further complicated by social difficulties noted in the other symptom category. Looking at repetitive behaviors that occur within the framework of ASD would suggest that providing or teaching more adaptive patterns of repetitive behavior would be a reasonable treatment or support response to the repetitive behaviors that derive from such neurological exaggerations that required increased levels of repetitive behavior, combined with difficulty judging the social acceptability of these behaviors.

In contrast, the DSM5 (American Psychiatric Association, 2013) (American Psychiatric Association, 2013) defines OCD as the presence of obsessions, compulsions, or both. Obsessions are described as a combination of recurrent and persistent thoughts, urges, or images that are experienced, at some time during the disturbance, as intrusive and unwanted, and cause marked anxiety and distress, along with attempts to suppress or ignore such thoughts, impulses, or images or to neutralize them with some other thought or action. Compulsions are defined as repetitive behaviors (e.g., hand washing, ordering, checking) or mental acts (e.g., praying, counting, repeating words silently) in response to an obsession or according to rules that must be applied rigidly. These behaviors or mental acts are aimed at preventing or reducing distress or preventing some dreaded event or situation; however, these behaviors or mental acts either are not connected in a way that could realistically neutralize or prevent whatever they are meant to address, or they are clearly excessive.

Some common examples of OCD symptoms include obsessions such as:

  • Contamination
  • Safety
  • Doubting one’s memory or perception
  • Scrupulosity (need to do the right thing, fear of committing a transgression, often religious)
  • Need for order or symmetry
  • Unwanted, intrusive sexual/aggressive thought

And compulsions such as:

  • Cleaning/washing
  • Checking (e.g., locks, stove, iron, safety of children)
  • Counting/repeating actions a certain number of times
  • Arranging objects
  • Touching/tapping objects
  • Confessing/seeking reassurance
  • List making

In previous versions of the diagnostic manual, OCD was classified as an anxiety disorder, since the anxiety generated by obsessive thoughts, and efforts to alleviate anxiety through compulsive behaviors, was considered the primary clinical dynamic that generated this disordered pattern of behavior. In DSM5, OCD was reclassified as part of a chapter on repetitive behavior disorders, which includes conditions such as Hoarding Disorder and Excoriation (skin picking) Disorder, and Trichotillomania (hair pulling) (American Psychiatric Association, 2013). While the change in grouping does not appear to be based on evidence that anxiety is not a central mechanism in OCD, the shift highlights a variety of significant challenges and questions related to making reliable diagnoses that will facilitate effective treatment. These involve the challenge of making an appropriate differential diagnosis, assessment of co-occurring disorders, diagnostic over-shadowing of appropriate diagnoses, and a variety of other concerns. This focus on similarities in behavioral features, such as driven, repetitive behaviors instead of underlying emotional dynamics prompted this change. The shift in organization of diagnostic categories highlights the documented concerns related to the tendency for disorders to run in families. Based on this, it is important for clinicians to be reminded to look for a family history of the other anxiety disorders and OCD in family members when evaluating patients diagnosed with an ASD (Delorme et al, 2007).

Since excessive anxiety is considered one of the central underlying problems in OCD, the recommended and research supported treatments include: cognitive behavioral therapy to help patients identify and dispute inappropriate/obsessive thoughts, along with behavioral coaching and supports to prevent engaging in compulsive behaviors. These interventions often are coordinated with the use of anti-anxiety medications, to reduce the level of anxiety a patient experiences, to manageable levels, while the other treatment processes are implemented. In limited research, these treatment techniques also have been shown to be effective for patients with co-occurring ASD and OCD (Lemkuhl, 2007).

In order to provide the most appropriate treatment and supports, it is necessary to make an accurate diagnosis. This is complicated by several factors. First, since both disorders include repetitive behavior symptoms, it is necessary to make distinctions between those behaviors. This is complicated by the fact that similar behaviors may be caused by one disorder or the other. To make a distinction, clinicians need to look at other factors, including apparent motivation and relationship to thoughts, other behaviors, and life events. Evaluating thought patterns and the presence or absence of obsessive thoughts in individuals with ASD can be complicated by the fact that the other major symptom category in ASD includes deficits in social communication. These can range from individuals who are nonverbal to those who use a wide variety of language but apply it in an idiosyncratic manner. In addition to communication problems, many theorists have discussed both children and adults with autism have impairments in ‘‘theory of mind,’’ which can make it difficult for them to understand that other people think differently than they do. Along with other complex information processing, such as verbal information processing, central coherence, and executive functioning difficulties, it may be difficult for even verbal individuals with autism to describe their mental states, mental experiences, and even daily life experiences.

Along with these challenges, there are a variety of factors that can assist clinicians in making a differential diagnosis regarding repetitive behavior. First, as noted above, the diagnostic criteria for OCD indicate that compulsive thoughts cause distress and/or anxiety, and that repetitive behavior is an attempt to rid oneself of these repetitive thoughts or prevent a feared disaster. In contrast, many individuals with ASD find their repetitive behavior pleasurable or comforting rather than distressing. This can become a complex pattern of behavior though, as sometimes people with ASD over-stimulate themselves if they engage in a repetitive behavior for too long or may engage in agitated or explosive behaviors if the repetitive behavior is interrupted after they have been doing it for an extended period of time. Other factors that need to be taken into consideration include: the fact that in autism compulsions are more likely to be automatic and unconscious, while OCD compulsive behavior is generally brought on by obsessions. For example: an autism patient might constantly flap his hand back and forth in the air, seemingly without realizing that he is doing it, while an OCD patient might deliberately wash his hands exactly 24 times each day. In addition, ASD is strongly linked to genetic components, while OCD is more likely to be a response to life experiences. A case in point is that sometimes, Post-traumatic stress disorder can cause a patient to develop OCD as a way to deal with stress and anxiety, while ASD is usually present from birth, or identified in early childhood.

These are just several examples of the complex array of issues that need to be addressed in order to make a valid differential diagnosis or diagnosis of co-occurring disorders. The overlapping pattern of behaviors described above, combined with these challenges highlights the importance of several goals that should be pursued, both in the effort to optimize treatment and support for individuals who may struggle with repetitive behavior that may not have responded to prior treatment, along with needs to pursue more in-depth research regarding the relationship between ASD and OCD. First, it is important for the field to establish more clinicians who are familiar with the differential diagnostic challenges noted above, along with the variety of more detailed questions and concerns that go into making the best possible clinical decisions for the individual patient. Along with this need, the large number of patients who present with these needs, and the difficulty finding successful treatment and support plans, indicate a need to develop additional clinical and diagnostic strategies and tools. Finally, a number of theorists have argued that part of the difficulty making accurate diagnoses and developing successful treatment plans may be related to questions about whether the current diagnostic scheme adequately explains the nature of these repetitive behaviors, and the relationship between those patterns that have historically been identified as either ASD or OCD. Potential solutions that have been suggested include the possibility that there may be an additional relationship between these disorders, such as an autistic subtype of OCD (Bejerot, 2007).

Philip Smith, PhD, is Assistant Professor of Pediatrics and Project Manager of Community Positive Behavior Supports at The Boggs Center on Developmental Disabilities at Rutgers Robert Wood Johnson Medical School. For more information, please visit


American Psychiatric Association (APA). (2013). Diagnostic and Statistical Manual of Mental Disorders. 2013. American Psychiatric Association. books.9780890425596

Bejerot, S. (2007). An autistic dimension A proposed subtype of obsessive-compulsive disorder. SAGE Publications and The National Autistic Society Vol 11(2) 101–110;

Bodfish, J.W., Symons, F.J., Parker, D.E., and Lewis, M.H.. (2000). Varieties of Repetitive Behavior in Autism: Comparisons to Mental Retardation. Journal of Autism and Developmental Disorders, Vol. 30, No. 3.

Delorme, R., Goussé, V., Roy, I., Trandafir, A., Mathieu, F., Mouren-Siméoni, M-C., Betancur, C., and Leboyer, M. (2007). Shared executive dysfunctions in unaffected relatives of patients with autism and obsessive-compulsive disorder. European Psychiatry, January; 22(1): 32–38.

Lehmkuhl, H.D., Storch, E.A., James W. Bodfish, & Gary R. Geffken (2008). Brief Report: Exposure and Response Prevention for Obsessive Compulsive Disorder in a 12-year-old with Autism, Journal of Autism and Developmental Disorders, 38: 997-981.

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