Impaired response inhibition is related to neurodevelopmental disorders, such as Tourette's disorder (TD) and obsessive-compulsive disorder (OCD). Unlike OCD, in which neural correlates of response inhibition have been extensively... more
Impaired response inhibition is related to neurodevelopmental disorders, such as Tourette's disorder (TD) and obsessive-compulsive disorder (OCD). Unlike OCD, in which neural correlates of response inhibition have been extensively studied, TD literature is limited. By using a Stop-Signal task, we investigated the neural mechanisms underlying response inhibition deficits in TD compared to OCD and healthy controls (HCs). Twenty-three TD patients, 20 OCD patients and 22 HCs were scanned (3T MRI). Region-of-interest analyses were performed between TD, OCD and HCs. Performance was similar across all subject groups. During inhibition TD compared with HCs showed higher right inferior parietal cortex (IPC) activation. During error processing TD compared with HCs showed hyperactivity in the left cerebellum, right mesencephalon, and right insula. Three-group comparison showed an effect of group for error-related activation in the supplementary motor area (SMA). Post-hoc analyses showed hi...
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The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here... more
The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymmetries, in a harmonized multi-site study using meta-analysis methods. Volumetric asymmetry of seven subcortical structures was assessed in 15,847 MRI scans from 52 datasets worldwide. There were sex differences in the asymmetry of the globus pallidus and putamen. Heritability estimates, derived from 1170 subjects belonging to 71 extended pedigrees, revealed that additive genetic factors influenced the asymmetry of these two structures and that of the hippocampus and thalamus. Handedness had no detectable effect on subcortical asymmetries, even in this unprecedented sample size, but the asymmetry of the putamen varied with age. Genetic drivers of asymmetry in the hippocampus, thalamus and ...
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There is accumulating evidence for the role of fronto-striatal and associated circuits in obsessive-compulsive disorder (OCD) but limited and conflicting data on alterations in cortical thickness. To investigate alterations in cortical... more
There is accumulating evidence for the role of fronto-striatal and associated circuits in obsessive-compulsive disorder (OCD) but limited and conflicting data on alterations in cortical thickness. To investigate alterations in cortical thickness and subcortical volume in OCD. In total, 412 patients with OCD and 368 healthy adults underwent magnetic resonance imaging scans. Between-group analysis of covariance of cortical thickness and subcortical volumes was performed and regression analyses undertaken. Significantly decreased cortical thickness was found in the OCD group compared with controls in the superior and inferior frontal, precentral, posterior cingulate, middle temporal, inferior parietal and precuneus gyri. There was also a group × age interaction in the parietal cortex, with increased thinning with age in the OCD group relative to controls. Our findings are partially consistent with earlier work, suggesting that group differences in grey matter volume and cortical thickn...
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Obsessive-compulsive disorder (OCD) is a common neuropsychiatric disorder with moderate genetic influences and white matter abnormalities in frontal-striatal and limbic regions. Inconsistencies in reported white matter results from... more
Obsessive-compulsive disorder (OCD) is a common neuropsychiatric disorder with moderate genetic influences and white matter abnormalities in frontal-striatal and limbic regions. Inconsistencies in reported white matter results from diffusion tensor imaging (DTI) studies can be explained, at least partly, by medication use and between-group differences in disease profile and stage. We used a family design aiming to establish whether white matter abnormalities, if present in un-medicated OCD patients, also exist in their unaffected siblings. Forty-four OCD patients, un-medicated for at least the past 4 weeks, 15 of their unaffected siblings, and 37 healthy controls (HC) underwent DTI using a 3-Tesla MRI-scanner. Data analysis was done using tract-based spatial statistics (TBSS). Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) values were compared within seven skeletonised regions of interest (ROIs), i.e., corpus callosum, bilatera...
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Research Interests: Genetics, Psychology, Computer Science, Mental Health, Biology, and 14 moreMedicine, Prevention, Humans, PMC, Neuroimage, Journal Article, Mental Disorders, Neurological, Neurosciences, Brain Diseases, Multicenter Studies as Topic, Psychology and Cognitive Sciences, Brain Disorders, and Medical and Health Sciences
Frontostriatal and frontoamygdalar connectivity alterations in patients with obsessive-compulsive disorder (OCD) have been typically described in functional neuroimaging studies. However, structural covariance, or volumetric correlations... more
Frontostriatal and frontoamygdalar connectivity alterations in patients with obsessive-compulsive disorder (OCD) have been typically described in functional neuroimaging studies. However, structural covariance, or volumetric correlations across distant brain regions, also provides network-level information. Altered structural covariance has been described in patients with different psychiatric disorders, including OCD, but to our knowledge, alterations within frontostriatal and frontoamygdalar circuits have not been explored. We performed a mega-analysis pooling structural MRI scans from the Obsessive-compulsive Brain Imaging Consortium and assessed whole-brain voxel-wise structural covariance of 4 striatal regions (dorsal and ventral caudate nucleus, and dorsal-caudal and ventral-rostral putamen) and 2 amygdalar nuclei (basolateral and centromedial-superficial). Images were preprocessed with the standard pipeline of voxel-based morphometry studies using Statistical Parametric Mappi...
Research Interests: Psychology, Cognitive Science, Psychiatry, Magnetic Resonance Imaging, Aging, and 15 moreMedicine, Linear models, Biological Psychiatry, Humans, Female, Male, Obsessive Compulsive Disorder, Psiquiatria, Clinical Sciences, Adult, Limbic System, Compulsive behavior, Cross Sectional Studies, Neurosciences, and Nervous System Diseases
Research Interests: Psychology, Bipolar Disorder, Magnetic Resonance Imaging, Medicine, Prefrontal Cortex, and 15 moreFMRI, Emotions, Response Inhibition, Brain, Humans, Facial expressions, Major Depressive Disorder, Female, Male, Middle Aged, Cognitive impairment, Adult, Functional Neuroimaging, Cross Sectional Studies, and Case Control Studies
Research Interests: Neuroscience, Psychology, Cognitive Science, Cognition, Magnetic Resonance Imaging, and 15 morePrefrontal Cortex, Executive Function, Cognitive Flexibility, Humans, Functional Magnetic Resonance Imaging, Female, Male, Aged, Middle Aged, Adult, Parietal Lobe, Neuropsychologia, Neurosciences, Parkinson Disease, and Psychomotor Performance
Behavioral impairments in response inhibition and initiation are common in Parkinson's disease (PD) and are associated with reduced impulse control. No prior study, however, has investigated the functional correlates of response... more
Behavioral impairments in response inhibition and initiation are common in Parkinson's disease (PD) and are associated with reduced impulse control. No prior study, however, has investigated the functional correlates of response inhibition in de novo PD. Twenty-one de novo PD patients and 37 matched healthy controls performed a stop-signal task during functional magnetic resonance imaging. The results showed that PD patients, compared with healthy controls, were slower on response initiation but not inhibition. Task-related activation of the response inhibition network, including the inferior frontal gyrus, was reduced in PD patients, and the activity in the inferior frontal gyrus correlated negatively with motor symptom severity. These findings show that de novo PD patients exhibit functional deficits in the response inhibition network, which are partly related to disease pathology and already evident before commencing dopamine replacement therapy. This study provides insights ...
Research Interests: Neuroscience, Psychology, Magnetic Resonance Imaging, Medicine, Prefrontal Cortex, and 15 moreHumans, Impulse Control Disorders, Functional Magnetic Resonance Imaging, Female, Functional Imaging, Male, Clinical Sciences, Aged, Middle Aged, Inferior frontal gyrus, Parkinson´s Disease, Neurosciences, Parkinson Disease, Psychomotor Performance, and Severity of Illness Index
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Research Interests: Psychology, Cognitive Science, Psychiatry, Magnetic Resonance Imaging, Medicine, and 15 moreBrain, Humans, Female, Male, Obsessive Compulsive Disorder, Clinical Sciences, Adult, Functional Neuroimaging, Neural pathways, Neurosciences, Frontal Lobe, Cognition disorders, Corpus striatum, Psychology and Cognitive Sciences, and Medical and Health Sciences
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Research Interests: Mathematics, Computer Science, Algorithms, Statistical Analysis, Medicine, and 15 moreBrain Mapping, Brain, Humans, Attenuation Correction, Neuroimage, Obsessive Compulsive Disorder, Clinical Sciences, Single Photon Emission Computed Tomography, Clinical Data, Reproducibility of Results, Attenuation, Iterative Reconstruction, False Positive, Psychology and Cognitive Sciences, and Medical and Health Sciences
Research Interests: Algorithms, Fear, Image Registration, Brain Mapping, Humans, and 15 moreAttenuation Correction, Female, Neuroimage, Obsessive Compulsive Disorder, Artifacts, Image Enhancement, Adult, Sensitivity and Specificity, Human Subjects, Motion Correction, False Negative, Motor activity, False Positive, Psychology and Cognitive Sciences, and Medical and Health Sciences
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In the present study, we sought to investigate which brain structures are recruited in planning tasks of increasing complexity. For this purpose, a parametric self-paced pseudo-randomized event-related functional MRI version of the Tower... more
In the present study, we sought to investigate which brain structures are recruited in planning tasks of increasing complexity. For this purpose, a parametric self-paced pseudo-randomized event-related functional MRI version of the Tower of London task was designed. We tested 22 healthy subjects, enabling assessment of imaging results at a second (random effects) level of analysis. Compared with baseline, planning activity was correlated with increased blood oxygenation level-dependent (BOLD) signal in the dorsolateral prefrontal cortex, striatum, premotor cortex, supplementary motor area, and visuospatial system (precuneus and inferior parietal cortex). Task load was associated with increased activity in these same regions. In addition, increasing task complexity was correlated with activity in the left anterior prefrontal cortex, a region supposed to be specifically involved in third-order higher cognitive functioning.
Research Interests: Computer Science, Magnetic Resonance Imaging, Attention, Functional MRI, Medicine, and 15 moreBrain Mapping, Humans, Cerebral Cortex, Female, Male, Magnetic Resonance, Middle Aged, Adult, Cognitive Function, Basal ganglia, Brain Structure, Healthy Subjects, Dorsolateral Prefrontal Cortex, Corpus striatum, and Medical and Health Sciences
In this paper, we tentatively bring together the psychiatric, neurological and addiction perspectives on the impulsive-compulsive spectrum of neuropsychiatric disorders, in order to understand the pathophysiology of impulse control... more
In this paper, we tentatively bring together the psychiatric, neurological and addiction perspectives on the impulsive-compulsive spectrum of neuropsychiatric disorders, in order to understand the pathophysiology of impulse control disorders (ICDs) in Parkinson's disease. In an attempt to try to pool the various levels of information we will therefore focus on three disorders within the impulse-compulsive spectrum, i.e., obsessive-compulsive disorder (OCD), ICDs in Parkinson's disease, and cocaine seeking behaviour. Whereas there are large differences between these three domains, each with their own nomenclature, hypotheses and study results, they share the focus on an imbalance within and between the frontal-striatal circuits as underlying substrate for the behaviours. For each disorder, we summarize the results from recent studies in order to describe in which way alterations in the frontal-striatal circuits contribute to the phenotype. The phenomenological overlap between ICDs in Parkinson's disease, addiction and OCD needs further investigation, since better understanding of the overlapping and differentiating characteristics will contribute to our understanding of the pathophysiology of the disturbances and treatment alternatives.
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Research Interests:
Research Interests: Psychology, Cognitive Science, Depression, Medicine, Humans, and 13 moreCaudate Nucleus, Female, Male, Clinical Sciences, Aged, Middle Aged, Retrospective Studies, Cross Sectional Studies, Parkinson´s Disease, Putamen, Parkinson Disease, Psychology and Cognitive Sciences, and Medical and Health Sciences
ObjectiveThe need for symmetry and ordering objects related to a “just right”-feeling is a common symptom in Tourette's syndrome (TS) and resembles symmetry behavior in obsessive-compulsive disorder, but its pathophysiology is... more
ObjectiveThe need for symmetry and ordering objects related to a “just right”-feeling is a common symptom in Tourette's syndrome (TS) and resembles symmetry behavior in obsessive-compulsive disorder, but its pathophysiology is unknown. We used a symptom provocation paradigm to investigate the neural correlates of symmetry behavior in TS and hypothesized the involvement of frontal-striatal and limbic brain areas.MethodsPictures of asymmetrically and symmetrically arranged objects were presented in randomized blocks (4 blocks of each condition) to 14 patients with TS and 10 matched healthy controls (HC). A H215O positron emission tomography scan was acquired during each stimulus block, resulting in 8 scans per subject. After each scan, state anxiety and symmetry behavior (the urge to rearrange objects) were measured using a visual analogue scale.ResultsDuring the asymmetry condition, TS patients showed increased regional cerebral blood flow (rCBF) in the anterior cingulate cortex,...