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Phenomenological Overlap Between the
Obsessive-Compulsive and Autism
Spectrums
Gregory S. Chasson, Ph.D.
Department of Psychology
Towson University
Licensed Clinical Psychologist
CBT Solutions of Baltimore
WHAT IS OCSD
� Linked because of similar
� Genetic and family risk factors
� Neurocognitive profiles (e.g., local
processing)
� Response to behavioral and
pharmacological interventions
� Pathophysiology (e.g., Striatrum)
� Symptom function and
presentation (e.g., compulsive
behavior)
� Traits (e.g., perfectionism)
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WHAT IS OCSD
OBSESSIVE-COMPULSIVE DISORDER (OCD) (APA, 2000)
� Obsessions = repetitive thoughts, impulses, or images
� Intrusive
� Inconsistent with values and self-image (i.e., ego-dystonic)
� Distressing� fear, disgust, guilt, etc.
� Compulsions = repetitive responses to obsessions
� Serve to decrease distress elicited by obsessions
� Can be mental or behavioral
� Can manifest as ritualistic, avoidance, or escape behaviors
WHAT IS OCSD
OBSESSIVE-COMPULSIVE DISORDER (OCD)
� Symptom themes:
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WHAT IS OCSD
Body Dysmorphic Disorder (BDD) (APA, 2000)
� Preoccupation with body part(s); > 1 hr/day
� Imagined defect, or if real, negligible to others
� Distressing� fear, disgust, guilt, etc.
� Common body parts: skin, nose, lips, hair, stomach, and size of breasts, penis, or muscles
� Compulsions = repetitive responses to preoccupations
� Serve to decrease distress elicited by preoccupations
� Can manifest as ritualistic, avoidance, or escape behaviors
� Examples: touching, checking, grooming, camouflaging, reassurance seeking, seclusion, etc.
WHAT IS OCSD
Tourettes Syndrome and Tic Disorders (APA, 2000)
� Tic = seemingly involuntary movement or vocalization
� Motor tic examples: nose crunch, facial grimace, mouth movement, eye movement, head turn, shoulder shrug
� Vocal tic examples: sniffing, coughing, throat clearing, repeating words or statements, animal noises, coprolalia.
� Premonitory Urge
� Tics preceded by the build-up of an urge, often in the bodily location of the tic
� For vocal tics, the urge often occurs in the throat or mouth
� Commonly reported as a tension or burning
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WHAT IS OCSD
Trichotillomania, Dermatillomania, and other Habits (APA, 2000)
� Trichotillomania (TTM) = pathological hair pulling habit
� Dermatillomania (DTM) = pathological skin picking habit
� Common features of habits
� Often prompted by stress, boredom, or tactile sensations (e.g., feeling the texture of the hair)
� Often, but not always, preceded by an urge
� Often, but not always, followed by a sense of relief
� Not uncommon for patients to eat or save pulled hair or picked skin
WHAT IS OCSD
Hoarding Disorder (Mataix-Cols et al., 2010)
� Excessive saving of items that most would consider valueless
� Examples: bottle caps, newspapers and magazines, string, junk
� Difficulty discarding the valueless items
� Various beliefs, such as 1) the item may be needed later, 2) it has
sentimental value, 3) it’s aesthetically pleasing and shouldn’t be
discarded
� The pathological acquisition and difficulty discarding often lead
to substantial clutter
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WHAT IS OCSD
Hypochondriasis (APA, 2000)
� Preoccupation with the belief that one has a disease, despite
disconfirming evidence
� Misinterprets normal bodily signs as markers of the disease
� Compulsions to gain disconfirmation or verification of disease
� Seek physician reassurance and testing, scan and check body for
signs and symptoms, explore internet resources endlessly
WHAT OF ASD & OCSD?
Diagnostically
� For comorbid OCD diagnoses in samples with ASD, rate has ranged
widely between 1.5% and 81% (Leyfer et al., 2006)
� Likely due to methodological variability
� Conversely, between 3% and 7% of individuals diagnosed with OCD also
meet diagnosis for Asperger’s (LaSalle et al., 2004)
� Thus, 6 to 14 times the prevalence rate of Asperger’s Disorder in
those with OCD compared to the general population (i.e., .48%
prevalence) (Fombonne & Tidmarsh, 2003)
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WHAT OF ASD &OCSD?
Subthreshold
� OCD symptoms are among the most common anxiety manifestations in
ASD (Gillott, Furniss, & Walter, 2001; Russell & Sofronoff, 2005)
� As many as 20% of individuals with OCD may have autistic features (Bejerot,
2006; Bejerot, Nylander, & Lindstrom, 2001)
STATE OF THEORY
� Unclear if overlap between ASD and OCSD is best characterized
as (Chasson et al., 2011)
� An illusion of resemblance
� An autistic subtype of OCD (Bejerot, 2007)
� A specific autistic-compulsive syndrome (Gross-Isseroff et al., 2001)
� The convergence of different clusters of features within OCSD (Hollander, 2005)
� None, some, or all of the above.
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BREAKING DOWN AUTISM
WHERE TO START?
� At this time, language deficiencies not a huge target of research on
OCSD/ASD overlap
� It’s not a universal characteristic of ASD (e.g., Aspergers), and not a
common problem in OCSD
� Social impairment, perhaps the cardinal feature of ASD, has only
recently received attention in the OCSD literature.
� Repetitive and restricted behavior is the obvious area of overlap
� So let’s start there
� But first, a caveat…
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REPETITIVE PHENOMENA
� Research on repetitive phenomena is riddled with methodological problems
� Poorly characterized samples
� Conflation of ego-syntonic and ego-dystonic thoughts
� Disregard for the function of repetitive behavior
� Failure to consider insight , IQ, communication deficits
� Measurement challenges
� Thoughtless comparison groups
� Disregard for Type I error
REPETITIVE PHENOMENA
� Bodfish (2011) has been the most accurate in characterizing the
difference in OCD and ASD repetitive phenomenon
� The function of repetitive behavior in ASD is heterogeneous
� Functions to provide pleasure
� Functions to reduce overall or specific stress
� Not necessarily ego-syntonic or elicited by an ego-syntonic
thought, image or impulse
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REPETITIVE PHENOMENA
� According to Bodfish (2011), the function of repetitive behavior in
OCD is more homogenous
� Functions to reduce specific stress from an ego-dystonic thought,
image or impulse, or
� The behavior itself is perceived as ego-dystonic
� Functionally, behavior in OCD and autism are similar only when
they serve to decrease specific stress associated with an ego-
dystonic thought
REPETITIVE PHENOMENA
� Most studies do not account for the function of the repetitive behavior, or they do not discuss it at all, leaving the reader to guess if it was addressed
� Evidence from the best available research suggests
� Obsessions in ASD tend to involve folk physics, or an ego-syntonic interest in how objects and machines work (Baron-Cohen
and Wheelwright , 1999)
� Compulsions elicited by ego-syntonic obsessions are often pleasurable
� However, individuals with ASD can still present with clinically signifcant ego-dystonic obsessions and compulsions (Russell,
Mataix-Cols, Anson, and Murphy,2005)
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REPETITIVE PHENOMENA
� Not everything fits neatly into Bodfish’s (2011) conceptualization
� His conceptualization is elegant but generally only distinguishes between OCD and ASD, not OCSD and ASD
� OCSD with functional pleasure: Trichotillomania, Dermatillomania, Hoarding
� Ego-syntonicity might not be a categorical phenomenon
� Not Just Right Experiences
� Similar pathophysiology—striatum
� Tics = ego-dystonic, but considered distinct from an OCD repetitive behavior
� Similar purported mechanisms of behavioral treatment—extinction
� Habit Reversal Training, Direct Reinforcement of Other, Exposure and Response Prevention
REPETITIVE PHENOMENA
� So, the jury is still out. There is no universal rule to differentiate repetitive phenomena in OCSD versus ASD
� Best bet is to ask,
� “What is the function of the behavior?”
� “To what degree is the patient’s experience ego-dystonic?”
� “To what degree is the patient obtaining pleasure from the behavior?”
� “Is this a behavioral response to a specific distressing thought, image, or impulse?”
� The best-guess differentiation lies in the pattern of answers to these questions, rather than the answer to any one question
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GOING BACK…
SOCIAL COMPETENCE
� Social competence impairment is not specific to ASD
� This is a common clinical correlate or presentation in multiple
psychiatric conditions (e.g., Schizophrenia) (Pousa et al., 2008)
� Social competence may reflect multiple underlying
endophenotypes that transcend traditional nosological boundaries (Chasson et al., 2011)
� Evidence for social competence impairment is just starting to
emerge in the literature on OCSD
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SOCIAL COMPETENCE
(Chasson et al., 2011)
SOCIAL COMPETENCE
� OCD probands and relatives exhibit more difficulties with pragmatic social rules (e.g., exchanging pleasantries) compared to healthy control counterparts (Cullen et al., 2008)
� Parental-report suggests that children with OCD have more difficulty with social self-control (e.g., spontaneous initiation of social behaviors) (Adams, 1995)
� Individuals with OCD have demonstrated elevated rates of shyness (Ivarsson & Winge-Westholm, 2004) and social anxiety disorder (Angst et al., 2004). Individuals with BDD have shown pronounced elevations in social anxiety severity (Wilhelm, Otto, Zucker, & Pollack, 1997)
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SOCIAL COMPETENCE
� Individuals with OCD may have difficulty processing
emotions displayed by faces (Corcoran, Woody, and Tolin, 2008;
Sprengelmeyer et al. ,1997)
� According to work by Feusner et al. (2007), individuals
with BDD process faces similar to those with ASD
(Deruelle et al. , 2004). They use brain pathways associated
with high-spatial frequency perception to process low-
and normal-spatial frequency faces
� Individuals with BDD and ASD visually process
faces using brain pathways designed for visually
processing inanimate objects (Schultz et al., 2000)
SOCIAL COMPETENCE
� Much like in ASD (Happe & Frith, 2006), individuals with OCD
and BDD present with local processing biases and
set-shifting difficulties (Deckersbach et al., 2000; Savage et al.,1999)
� These neuropsychological tendencies may be related
to social competence impairments (Aigner et al., 2007)
� Local processing tendencies may cause individuals
with OCD and BDD to miss global features when
processing faces, and set-shifting difficulties could
hinder their ability to transition visually from one facial
feature to another
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SOCIAL COMPETENCE
� Social competence abnormalities may be particularly
heritable (Bolton, Pickles, Murphy, & Rutter, 1998) and
genetically independent of other facets of autism (Ronald
et al., 2006)
� A rare missense I425V mutation in the SERT gene
may be associated with psychiatric disorders with
social dysfunction (e.g., ASD, social phobia, OCD) (Wendland et al., 2008)
� The mutation = an A to G transversion substituting
Val425 for Ile425 that results in a gain-of-function
of SERT (Chasson et al., 2011)
SOCIAL COMPETENCE
� Serotonin and dopamine have both been implicated in social processing in OCSD and ASD populations
� Based on pharmacotherapy studies (Jenike, 2004;
McDougle et al., 1996)
� Glutamate has been implicated in social processing impairment (Montag, Schubert, Heinz, & Gallinat, 2008), as well as the pathophysiology of OCD (Chasson et al., 2010) and ASD (Jamain et al., 2002; Shuang et al., 2004)
� Oxytocin facilitates social connectedness and may play a role in both OCD (e.g., Altemus et al., 1999) and ASD (e.g., Bartz & Hollander, 2006, 2008; Bejerot, 2006; Insel, O'Brien, & Leckman, 1999).
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SOCIAL COMPETENCE
� The amygdala has been proposed to play a critical
role in early-stage processing of facial emotion (Chasson
et al., 2011), and is hypothesized to play an important role
in a proposed social processing neural circuit (Brothers,
Ring, and Kling, 1990)
� Irregularities in structure and function of the amygdala
have been demonstrated in individuals with OCD (Britton
et al., 2010; Cannistraro et al., 2004) and ASD (Baron-Cohen et al., 2000;
Mosconi et al., 2009)
SOCIAL COMPETENCE
Concluding thoughts on OCSD/ASD and social competence impairment
� Remains unknown if any social competence impairments observed in ASD and
OCSD mostly arise before, during, or after onset of the disorder
� However, subtle abnormal social functioning is associated with genetic
risk.
� Thus, it’s unlikely that social competence impairments are solely caused
by inadequate or missed social development
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SOCIAL COMPETENCE
Concluding thoughts on OCSD/ASD and social competence impairment
� Formulating a theoretical framework for understanding the overlap between
OCSD and ASD may require integration of candidate endophenotypes
� Corroborating a link between OCSD and ASD may facilitate development of
new diagnostic, prevention, and intervention techniques.
� Because individuals who present with features of both disorders may be
more clinically severe (Bejerot, 2007) and resistant to treatment (Humble, Bejerot,
Bergqvist, & Bengtsson, 2001)
CONCULSION
� OCSD and ASD share many features, some in obvious ways (e.g., repetitive
behaviors) and some in not so obvious ways (e.g., social competence
impairment
� Future research would benefit from sampling that transcends codified
diagnostic categories. NIH seems to agree (see RDoC)
� Differentiating ASD and OCSD can be quite challenging in some cases.
� In some cases, there is a legitimate comorbidity between ASD and OCSD
� In some cases, comorbidity is superficial or inaccurate
� Sometimes, all you can do is provide an educated guess and treat the
patient as an n = 1 experiment
� Test different treatment approaches to see what works best
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