title: Pathophysiology of refractory obsessive-compulsive disorder: A study of visual search combined with overactive performance monitoring.
abstract: Based on both functional and structural studies of excessive activity, fronto-striatal-thalamic-cortical and cortico-striatal circuits have been hypothesized to underlie the pathophysiology of obsessive-compulsive disorder (OCD). However, the neurobiological underpinnings of OCD refractory to medication and therapy remain controversial. This study aimed to evaluate neuroanatomical abnormalities of the whole brain and to evaluate visual processing in patients with refractory OCD.This study was comprised of 2 experiments. The neuroanatomical abnormalities of the whole brain were evaluated using a visual search in combination with overactive performance monitoring (Experiment I), and visual processing was evaluated using event-related potentials recorded from subjects during performance of a visual search task. We also examined the amplitudes and latency of the error-related negativity (ERN) using a modified flanker task (Experiment II). Standard low-resolution electromagnetic tomography analysis was applied to determine the special areas.Patients with refractory OCD had a significantly greater number of saccades and prolonged latencies relative to the healthy controls. Scalp map topography confirmed that visual cognitive and executive dysfunction was localized to the fusiform gyrus. Furthermore, we found that during a modified flanker task, ERNs had a greater amplitude and a prolonged latency relative to those of the healthy controls. Further data analysis suggested that cognitive dysfunction and compulsive behavior in OCD patients were linked to abnormalities within the dorsolateral prefrontal cortex (DLPFC).We identified abnormal activities within the fusiform gyrus and DLPFC that likely play important roles in the pathophysiology of OCD.
authors.affiliation: Mental Health Centre, West China Hospital, Sichuan University Key Laboratory for Neuroinformation of the Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.
authors.forename: Qingxiao
authors.initials: Q
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Tan
authors.forename: Jing
authors.initials: J
authors.lastname: Zhou
authors.forename: Zhong
authors.initials: Z
authors.lastname: Zheng
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009771:Obsessive-Compulsive Disorder / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000628:therapy; D009778:Occipital Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time; D012438:Saccades; D013647:Task Performance and Analysis; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D014054:Tomography; D014796:Visual Perception; D055815:Young Adult