Most cited article - PubMed ID 21354363
EEG source analysis in obsessive-compulsive disorder
BACKGROUND: The underlying symptomatology of obsessive-compulsive disorder (OCD) can be viewed as an impairment in both cognitive and behavioral inhibition, regarding difficult inhibition of obsessions and behavioral compulsions. Converging results from neuroimaging and electroencephalographic (EEG) studies have identified changes in activities throughout the medial frontal and orbital cortex and subcortical structures supporting the cortico-striato-thalamo-cortical circuit model of OCD. This study aimed to elucidate the electrophysiological changes induced by autobiographical and general anxiety scenarios in patients with OCD. METHODS: Resting-state eyes-closed EEG data were recorded in 19 OCD patients and 15 healthy controls. Cortical EEG sources were estimated by standardized low-resolution electromagnetic tomography (sLORETA). The changes in the emotional state were induced by two different scenarios: the autobiographical script related to patient's OCD symptoms and the script triggering general anxiety. RESULTS: During the resting state, we proved increased delta activity in the frontal, limbic and temporal lobe and the sub-lobar area in OCD patients. In a comparison of neural activities during general anxiety in OCD patients and the control group, we proved an increase in delta (parietal, temporal, occipital, frontal and limbic lobes, and sub-lobal area), theta (temporal, parietal and occipital lobes) and alpha-1 activities (parietal lobe). Finally, we explored the neural activity of OCD patients during exposure to the autobiographic scenario. We proved an increase in beta-3 activity (left frontal lobe). CONCLUSION: Our study proved differences in neural activation in OCD patients and healthy controls during imagination of general anxiety. Exposure to the autobiographic OCD scenario leads to activation of left frontal brain areas. The results show the possibility of using specific scenarios in OCD therapy.
- Keywords
- anxiety, autobiographical script, cognitive-behavior therapy, electroencephalography, obsessive–compulsive disorder,
- Publication type
- Journal Article MeSH
Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder with 1-3% prevalence. OCD is characterized by recurrent thoughts (obsessions) and repetitive behaviors (compulsions). The pathophysiology of OCD remains unclear, stressing the importance of pre-clinical studies. The aim of this article is to critically review a proposed animal model of OCD that is characterized by the induction of compulsive checking and behavioral sensitization to the D2/D3 dopamine agonist quinpirole. Changes in this model have been reported at the level of brain structures, neurotransmitter systems and other neurophysiological aspects. In this review, we consider these alterations in relation to the clinical manifestations in OCD, with the aim to discuss and evaluate axes of validity of this model. Our analysis shows that some axes of validity of quinpirole sensitization model (QSM) are strongly supported by clinical findings, such as behavioral phenomenology or roles of brain structures. Evidence on predictive validity is contradictory and ambiguous. It is concluded that this model is useful in the context of searching for the underlying pathophysiological basis of the disorder because of the relatively strong biological similarities with OCD.
- Keywords
- OCD, animal model, brain circuits, human, quinpirole, rat,
- Publication type
- Journal Article MeSH
- Review MeSH
BACKGROUND: Obsessive-compulsive disorder (OCD) is associated with cognitive dysfunction. Although there are several studies focused on the neurobiology of OCD, little is known about the biological correlates of the cognitive deficit linked to this disorder. The aim of our study was to examine the association between cognitive impairment and current source density markers in patients with OCD. METHODS: Resting-state eyes-closed electroencephalography (EEG) data were recorded in 20 patients with OCD and 15 healthy controls who were involved in the study. Cortical EEG sources were estimated by standardized low-resolution electromagnetic tomography in seven frequency bands: delta (1.5-6 Hz), theta (6.5-8 Hz), alpha-1 (8.5-10 Hz), alpha-2 (10.5-12 Hz), beta-1 (12.5-18 Hz), beta-2 (18.5-21 Hz), and beta-3 (21.5-30 Hz). Cognitive performance was measured by the Trail-Making Test (versions A and B), Stroop CW Test, and D2 Test. RESULTS: Frontal delta and theta EEG sources showed significantly higher activity in the whole group of patients with OCD (N=20) than in control subjects (N=15). Subsequent analysis revealed that this excess of low-frequency activity was present only in the subgroup of eleven patients with cognitive impairment (based on the performance in the Trail-Making Test - A). The subgroup of patients with normal cognitive functions (N=9) did not differ in cortical EEG sources from healthy controls. CONCLUSION: The present results suggest that frontal low-frequency cortical sources of resting-state EEG rhythms can distinguish groups of cognitively impaired and cognitively intact patients with OCD. Based on our results, future studies should consider whether the present methodological approach provides clinically useful information for the revelation of cognitive impairment in patients with OCD.
BACKGROUND: The aim of the study was to determine whether patients with obsessive-compulsive disorder (OCD) resistant to drug therapy may improve their condition using intensive, systematic cognitive behavioral therapy (CBT) lasting for 6 weeks, and whether it is possible to predict the therapeutic effect using demographic, clinical, and selected psychological characteristics at baseline. METHODS: Sixty-six OCD patients were included in the study, of which 57 completed the program. The diagnosis was confirmed using the structured Mini International Neuropsychiatric Interview. Patients were rated using the objective and subjective forms of the Yale-Brown Obsessive Compulsive Scale, objective and subjective forms of the Clinical Global Impression, Beck Anxiety Inventory, Beck Depression Inventory, Dissociative Experiences Scale, 20-item Somatoform Dissociation Questionnaire, and the Sheehan Disability Scale before their treatment, and with subjective Yale-Brown Obsessive Compulsive Scale, objective and subjective Clinical Global Impression, Beck Anxiety Inventory, and Beck Depression Inventory at the end of the treatment. Patients were treated with antidepressants and daily intensive group CBT for the 6-week period. RESULTS: During the 6-week intensive CBT program in combination with pharmacotherapy, there was a significant improvement in patients suffering from OCD resistant to drug treatment. There were statistically significantly decrease in the scores assessing the severity of OCD symptoms, anxiety, and depressive feelings. A lower treatment effect was achieved specifically in patients who 1) showed fewer OCD themes in symptomatology, 2) showed a higher level of somatoform dissociation, 3) had poor insight, and 4) had a higher initial level of overall severity of the disorder. Remission of the disorder was more likely in patients who had 1) good insight, 2) a lower initial level of anxiety, and 3) no comorbid depressive disorder.
- Keywords
- cognitive behavioral therapy, obsessive–compulsive disorder, predictors, treatment, treatment efficacy, treatment resistance,
- Publication type
- Journal Article MeSH