Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a chronically debilitating disorder, with a marginally higher lifetime prevalence rate in Singapore. Earlier studies have been partly inconsistent in the structural basis of OCD. Most of these studies employed a voxel-based morphometry approach and evaluated on...

Full description

Bibliographic Details
Main Author: Teo, Jia Li
Other Authors: Chen Shen-Hsing Annabel
Format: Final Year Project (FYP)
Language:English
Published: 2019
Subjects:
Online Access:http://hdl.handle.net/10356/77236
_version_ 1826121655648256000
author Teo, Jia Li
author2 Chen Shen-Hsing Annabel
author_facet Chen Shen-Hsing Annabel
Teo, Jia Li
author_sort Teo, Jia Li
collection NTU
description Obsessive-compulsive disorder (OCD) is a chronically debilitating disorder, with a marginally higher lifetime prevalence rate in Singapore. Earlier studies have been partly inconsistent in the structural basis of OCD. Most of these studies employed a voxel-based morphometry approach and evaluated only volumetric alterations. Few studies have examined more specific sub-components, such as cortical thickness and area, which are phenotypically and genetically independent. Response inhibition, a candidate endophenotype in OCD, has often been emphasized as right-lateralized in imaging studies. While alterations in structural asymmetry have been widely studied and linked to cognitive and emotional disturbances in neuropsychiatric disorders, no studies have examined the link between structural asymmetry and response inhibition in OCD. Therefore, the present study investigated structural alterations in OCD using surface-based morphometry and examined for alterations in structural asymmetry associated with response inhibition and the pathology of OCD. T1-weighted structural magnetic resonance images were acquired from 19 patients with OCD and 21 controls. A whole-brain analysis was conducted using FreeSurfer v6.0 to examine for alterations in cortical thickness, area and volume in patients with OCD. Group differences in asymmetry indices of selected apriori response inhibition and cortico-striato-thalamo-cortical (CSTC) regions were also examined. Compared to controls, patients with OCD showed decreased area and volume in left superior-inferior parietal and occipital regions and increased volume in right supramarginal and postcentral regions. Patients with OCD also exhibited significant leftward asymmetries in several frontal regions, not observed in healthy controls. The present findings highlighted the importance of studying regions beyond the CSTC disease model and suggested potential structural asymmetry underlying inhibitory deficits, thereby prompting further investigation of the underlying mechanisms.
first_indexed 2024-10-01T05:36:04Z
format Final Year Project (FYP)
id ntu-10356/77236
institution Nanyang Technological University
language English
last_indexed 2024-10-01T05:36:04Z
publishDate 2019
record_format dspace
spelling ntu-10356/772362019-12-10T13:52:05Z Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder Teo, Jia Li Chen Shen-Hsing Annabel School of Social Sciences DRNTU::Social sciences::Psychology Obsessive-compulsive disorder (OCD) is a chronically debilitating disorder, with a marginally higher lifetime prevalence rate in Singapore. Earlier studies have been partly inconsistent in the structural basis of OCD. Most of these studies employed a voxel-based morphometry approach and evaluated only volumetric alterations. Few studies have examined more specific sub-components, such as cortical thickness and area, which are phenotypically and genetically independent. Response inhibition, a candidate endophenotype in OCD, has often been emphasized as right-lateralized in imaging studies. While alterations in structural asymmetry have been widely studied and linked to cognitive and emotional disturbances in neuropsychiatric disorders, no studies have examined the link between structural asymmetry and response inhibition in OCD. Therefore, the present study investigated structural alterations in OCD using surface-based morphometry and examined for alterations in structural asymmetry associated with response inhibition and the pathology of OCD. T1-weighted structural magnetic resonance images were acquired from 19 patients with OCD and 21 controls. A whole-brain analysis was conducted using FreeSurfer v6.0 to examine for alterations in cortical thickness, area and volume in patients with OCD. Group differences in asymmetry indices of selected apriori response inhibition and cortico-striato-thalamo-cortical (CSTC) regions were also examined. Compared to controls, patients with OCD showed decreased area and volume in left superior-inferior parietal and occipital regions and increased volume in right supramarginal and postcentral regions. Patients with OCD also exhibited significant leftward asymmetries in several frontal regions, not observed in healthy controls. The present findings highlighted the importance of studying regions beyond the CSTC disease model and suggested potential structural asymmetry underlying inhibitory deficits, thereby prompting further investigation of the underlying mechanisms. Bachelor of Arts in Psychology 2019-05-21T08:21:40Z 2019-05-21T08:21:40Z 2019 Final Year Project (FYP) http://hdl.handle.net/10356/77236 en 128 p. application/pdf
spellingShingle DRNTU::Social sciences::Psychology
Teo, Jia Li
Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title_full Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title_fullStr Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title_full_unstemmed Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title_short Structural alterations, asymmetry and response inhibition in obsessive-compulsive disorder
title_sort structural alterations asymmetry and response inhibition in obsessive compulsive disorder
topic DRNTU::Social sciences::Psychology
url http://hdl.handle.net/10356/77236
work_keys_str_mv AT teojiali structuralalterationsasymmetryandresponseinhibitioninobsessivecompulsivedisorder