Obsessive-Compulsive Disorders or Not: Differential Diagnosis of Repetitive Behaviors Among Individuals with Intellectual and Developmental Disorders

Abstract

This chapter focuses on the complex psychobiology of Obsessive-Compulsive Disorder (OCD) among individuals with Intellectual and Developmental Disabilities (IDD). It begins with OCD as an anxiety-driven psychiatric disorder characterized by intrusive thoughts and images (obsessions) and a tendency to engage in a select group of escape behaviors (compulsions) of sufficient severity to interfere with daily life. Using these criteria to diagnose OCD in persons with IDD frequently results in a heterogeneous disorder that overlaps other forms as repetitive behaviors (Baldwin et al 2008; Pallanti et al 2008). Resolving the heterogeneity issue requires that we differentiate OCD from related stereotypies, ritualistic behaviors, self-injurious behaviors (Flavell, 1982), and OC-related behaviors associated with Autistic Spectrum Disorders( ASD),Tourette’s Disorder (TD) and other movement disorders (Barnhill, 2008). To accomplish this task we will move beyond the descriptive criteria for OCD and anxiety disorders found in the Diagnostic and Statistical ManualIV-TR (APA, 2000) and the Diagnostic Manual-Intellectual Disability ( Fletcher et al, 2007). By the end of this review it will be readily apparent to the reader that OCD like other anxiety disorders represents a convergence of many functional abnormalities spread out across several neuro-anatomically distinct but functionally overlapping pathways. To reach this conclusion, we will come to understand that the symptomatic diversity of this group of disorders of repetitive thoughts and behaviors depends in large part on regional malfunctioning within a pathway or network rather than on any single “lesion” (Davis, 2002, Barnhill, 2008). We will begin this exploration by examining fear, fear conditioning and their role in anxiety disorders. To do this requires an analysis of new findings in the neurosciences, especially gene-environmental interactions, temperament, physiological responses to stressful environmental events and the mode of anxiety-related behavioral responses (Feinstein et al 2007; De Mathis et al 2006) . Later, we will shift to an ethological model that uses reciprocal social, ritualized and attachment behaviours to describe subtypes of anxiety. This approach can be a useful tool can be useful tool for classifying OC related behaviors among nonverbal patients with severeprofound IDD. The remainder of the chapter will address the relationship between OCD, Obsessive-Compulsive Spectrum Disorder (OCSD) and