Cognitive Biases in Obsessive-Compulsive Disorder : Manifestation in Implicit Measures of Attention, Approach-Avoidance and Aggression

Obsessive-compulsive disorder (OCD) has a lifetime prevalence of 2-3%. A diagnosis of OCD has serious implications for the individuals, as OCD is associated with extensive disability covering many aspects of functioning (e.g., social life and work), increased healthcare utilization, and reduced quality of life. Both, cognitive models of OCD and the emotional processing theory highlight the role of cognitive biases in the development and maintenance of OCD. These assumptions have been supported by empirical findings in several domains, including attention, approach-avoidance and aggression. The latter is associated with dysfunctional beliefs. The emotional processing theory assumes that cognitive biases are not necessarily available to the individual through introspection. However, to date the vast majority of studies has used only explicit measures to assess cognitive biases in OCD. Assumptions regarding implicit processes in OCD often rely on results from (analog) samples of individuals with anxiety disorders. Previous research using implicit measures to assess OC biases is scarce and has mostly examined analog samples. The current dissertation aimed at shedding light on three of those cognitive biases using implicit measures in patients with OCD. In three studies individuals with various subtypes of OCD, including patients with checking-related and contamination-related symptoms as well as a healthy control group were included. Attentional biases were assessed in patients with OCD (n = 28) and healthy controls (n = 21) using an eye tracker (study I). Participants were asked to view contamination-related, checking-related and neutral stimuli, in a free viewing paradigm. A possible vigilance bias was assessed using entry time and a maintenance bias using dwell time. An Approach-Avoidance Task (AAT) was used in study II to examine behavioral tendencies in patients with OCD (n = 63), compared to a healthy control group (n = 30). In the AAT, participants were asked to respond to the color of a stimulus or stimulus frame by pulling a joystick towards themselves or by pushing it away. Similar to the material used in study I, the stimuli in the AAT were checking-related, contamination-related, and neutral. Contrary to study I, both pictures and words were incorporated. In study III implicit aggression was investigated in patients with OCD (n = 58) and healthy controls (n = 25) with an Implicit Association Test (IAT), which is a reaction time task that assesses the strength of associations between the concept of aggressiveness and the categories me compared to others. No general bias could be found when assessing the whole sample of patients with OCD compared to healthy controls regarding attention, approach-avoidance and aggression. However, patients with checking-related symptoms of OCD showed cognitive biases in all three paradigms compared to healthy controls. Study I showed that they viewed checking-related pictures longer than neutral pictures, lending support for a maintenance bias of attention in the checking-related subtype of OCD. Additionally, they pulled checking-related stimuli faster and pushed them slower than a healthy control group in the AAT (study II). This suggests an approach rather than an avoidance bias in patients with checking-related symptoms. Furthermore, they showed a bias regarding aggression on the IAT (study III). However, contrary to hypotheses they did not show a more aggressive but a more peaceful implicit self-concept than healthy controls. Patients with contamination-related symptoms did not show any bias in either of the studies. The studies in the current dissertation were the first to assess patients with OCD to examine cognitive biases of attention, approach-avoidance and aggression with three implicit measures (eye tracking, AAT, and IAT). Results stand in contrast to previous studies using explicit measures. This might indicate that cognitive biases are influenced by processes which may not be fully assessable by explicit measures. Thus, implicit measures may prove to be important to extend previous research on cognitive biases in OCD. Furthermore, results differ from findings on anxiety disorder and most studies in subclinical samples, often assessing contamination fears only. Previous studies on attentional biases have found a vigilance bias and not a maintenance bias in anxiety disorders. Moreover, in both anxiety disorders and subclinical participants with contamination fears, an avoidance bias was found in the AAT. Hence, the discrepancy between the results of the current dissertation and prior results from studies using implicit measures in anxiety disorders underline possible differences in information processing of the two disorders, which has recently led to the separate classification of OCD and anxiety disorders in the DSM-5. Furthermore, the results of the current dissertation emphasize the issues inherent in studying OCD, due to its heterogeneity. Future studies should incorporate idiosyncratic material to better conceptualize implicit measures for the various symptoms of the disorder. Moreover, clinical control groups could help to better understand the specificity of the cognitive biases for OCD. The current dissertation showed that implicit measures could be useful in assessing cognitive biases in OCD and to better understand underlying mechanisms of the disorder. Eventually, they might also prove to be useful as a diagnostic tool, in the assessment of treatment gains and as a complementary training tool in OCD.