Thomas Johansen

Cognitive deficits of executive functions and decision-making in obsessive-compulsive disorder

The nature of cognitive deficits in obsessive-compulsive disorder (OCD) is characterized by contradictory findings in terms of specific neuropsychological deficits. Selective impairments have been suggested to involve visuospatial memory, set shifting, decision-making and response inhibition. The aim of this study was to investigate cognitive deficits in decision-making and executive functioning in OCD. It was hypothesized that the OCD patients would be less accurate in their responses compared to the healthy controls in rational decision-making on a version of the Cambridge gambling task (CGT) and on the color-word interference test and on a version of the Tower of Hanoi test (tower test) of executive functioning. Thirteen participants with OCD were compared to a group of healthy controls (n = 13) matched for age, gender, education and verbal IQ. Results revealed significant differences between the OCD group and the healthy control group on quality of decision-making on the CGT and for achievement score on the tower test. On these two tasks the OCD group performed worse than the healthy control group. The symptom-dimension analysis revealed performance differences where safety checking patients were impaired on the tower test compared to contamination patients. Results are discussed in the framework of cognition and emotion processing and findings implicate that OCD models should address, specifically, the interaction between cognition and emotion. Here the emotional disruption hypothesis is forwarded to account for the dysfunctional behaviors in OCD. Further implications regarding methodological and inhibitory factors affecting cognitive information processing are highlighted.

Cognitive Performance in a Subclinical Obsessive-Compulsive Sample 1: Cognitive Functions

Individuals who are not clinically diagnosed with obsessive-compulsive disorder (OCD) but still display obsessive-compulsive (OC) tendencies may show cognitive impairments. The present study investigated whether there are subgroups within a healthy group showing characteristic cognitive and emotional performance levels similar to those found in OCD patients and whether they differ from OCD subgroups regarding performance levels. Of interest are those cases showing subclinical symptomatology. The results revealed no impairments in the subclinical OC participants on the neuropsychological tasks, while evidence suggests that there exist high and low scores on two standardised clinical instruments (Yale-Brown Obsessive Compulsive Scale and Cognitive Assessment Instrument of Obsessions and Compulsions) in a healthy sample. OC symptoms may diminish the quality of life and prolong sustainable return to work. It may be that occupational rehabilitation programmes are more effective in rectifying subclinical OC tendencies compared to the often complex symptoms of diagnosed OCD patients. The relationship between cognitive style and subclinical OC symptoms is discussed in terms of how materials and information might be processed. Although subclinical OC tendencies would not seem to constitute a diagnosis of OCD, the quality of treatment programmes such as cognitive behavioural therapy can be improved based on the current investigation.

Clinical and neurocognitive changes with modafinil in obsessive-compulsive disorder: a case report.

There are limited treatment options for co-occurring sleep disorders and obsessive–compulsive disorder (OCD). We postulated that Modafinil (Provigil) [2-{(diphenylmethyl) sulfinyl acetamide}], a non-amphetamine wakefulnesspromoting agent, might be of value in patients with excessive daytime sleepiness (EDS). Randomized double-blind placebo-controlled depression trials have investigated the effects of modafinil co-administered with selective serotonin re-uptake inhibitors (SSRIs) and found improvement in clinical global scores, and aside from effects on sleep and mood, modafinil has exhibited cognitive enhancing effects in some subjects (Minzenberg and Carter 2008). In a doubleblind placebo-controlled crossover challenge, Turner et al. (2004) demonstrated decreased motor impulsivity as measured on laboratory tests in adult attention-deficit/ hyperactivity disorder patients treated with single doses of modafinil (100 mg and 200 mg). To date, studies examining the neuropsychological effects of treatment are rare in OCD and have generally failed to show a positive effect of SSRI treatment on cognition (Nielen and den Boer 2003). In this context, we considered a new approach for treating neurocognitive impairments in treatment-resistant OCD. Modafinil’s effects on clinical symptoms and on a selected range of neurocognitive functions previously reported to be impaired in OCD (Chamberlain et al. 2005) are examined. We report the case of a patient with treatment-resistant OCD and EDS treated with adjunctive modafinil. DW is a 33-year-old unemployed man with a 13-year history of aggressive obsessions, panic anxiety, low mood, and EDS. Past treatment with dothiepin, venlafaxine, and several SSRIs had produced little benefit. A primary diagnosis of SSRI-resistant, DSM-IV OCD (defined as less than 25% improvement on the Yale-Brown Obsessive– Compulsive Scale (Y-BOCS) despite adequate treatment trials) was made, with DSM-IV panic disorder and DSM-IV dysthymia as subsidiary diagnoses. His sleep schedule was chaotic, with sleeping periods during the day, though he tended to get up at 8 am irrespectively. At initiation of modafinil, DW (right-handed, no sensory impairments) had been receiving escitalopram (40 mg) for at least 12 weeks being administered unchanged throughout the trial. A single morning dose of modafinil (100 mg) was prescribed and increased after 3 weeks to 200 mg (in two divided doses), and after 4 weeks to 400mg (in two divided doses). Treatment adherence was checked verbally. Clinical assessments were W. H. Dittrich (*) Medical School, Office of the Dean, Goethe-University Frankfurt am Main, Haus 15B, Zi. 418, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany e-mail: winand.dittrich@kgu.de

Pointing and the interference effect in obsessive-compulsive disorder (OCD)

The interference effect in obsessive-compulsive disorder (OCD) was investigated in order to analyze cognitive aspects of motor stereotypy in OCD-related compulsions. So far, the domain of cognitive control in compulsive behavior has been under-investigated. Twelve participants (OCD patients and healthy controls) completed a newly created computer-based pointing task as well as standard clinical and psychological background measures. Findings showed that the patients displayed a larger visual interference effect compared to the controls and pointing paths were longer in time as well as distance when a distractor stimulus was present. It is concluded that, for compensation, patients would need to generate excessive amounts of attentional resources not available to overcome motor rigidity on the one side and visual distraction on the other side.

Cognitive performance in a subclinical obsessive-compulsive sample: Emotional processing and quality of life

Abstract There is a stronger focus on understanding emotional processing in obsessive-compulsive disorder (OCD). This follows the assumption that the orbitofrontal cortex may be impaired. The ability to recognize and name odours probe emotional processing and thus orbitofrontal cortex functioning. The aim of this exploratory study was to investigate whether olfactory naming performance in individuals reporting subclinical obsessive-compulsive (OC) tendencies is impaired. This would allow a better understanding of differences and similarities in emotional processing between OCD patients and individuals reporting OC tendencies. The assessment of OC tendencies was measured with two standardized questionnaires (Yale-Brown Obsessive Compulsive Disorder Scale and Cognitive Assessment Instrument of Obsessions and Compulsions). The performance on a smell naming test in a subclinical group was compared to a group of individuals not reporting OC tendencies, and constituted the nonclinical control group. The subclinical group performed to the same standard as the nonclinical control group in naming both unpleasant and pleasant smells. It cannot be assumed that individuals showing OC tendencies are impaired in emotional processing as found in diagnosed OCD patients. Nevertheless, it is argued that the interaction between cognition and emotion, for example, intact attentional processing of emotional information is vital to reduce the intensity, frequency and duration of OC tendencies, thus underpinning experiences that promote better quality of social and working life.

Changes in cognitive functioning in sick-listed participants in occupational rehabilitation: A feasibility study.

Abstract Background: Individuals on long-term sick leave attending occupational rehabilitation often complain about impairments in cognitive functions such as memory and attention. Knowledge of cognitive functioning in these individuals is limited. Such knowledge is clinically relevant for improving occupational rehabilitation programmes. Objective: The aims of this feasibility study were to assess the methodological design and to investigate changes in memory and attention on participants during occupational rehabilitation. Methods: Individuals attending occupational rehabilitation (n = 28) and individuals working full time (n = 25) matched for age, gender, and education participated. The two groups were administered cognitive tests targeting memory and attention and self-reported questionnaires at pre-test and post-test. Outcome measures were speed and accuracy of responses on the cognitive tests and self-reported work ability, subjective health complaints, and symptoms of depression and anxiety. Results: In total, 35% of all invited participants agreed to take part and 93% of these also completed the second test. The mean gain scores in the intervention group were significantly higher than in the control group in response latency on simple and choice reaction time and errors in spatial working memory. Conclusion: The results of this study indicate that the motivation of participants to complete testing was high. Improvements in memory and attention were evident in rehabilitation participants indicating that rehabilitation may have an effect on cognitive functions.