ORCID Profile
0000-0002-5517-2665
Current Organisations
University of Colorado at Boulder
,
University of Barcelona
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Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-07-2017
DOI: 10.1097/J.PAIN.0000000000000985
Abstract: A relevant aspect in osteoarthritic pain is neural sensitization. This phenomenon involves augmented responsiveness to painful stimulation and may entail a clinically worse prognosis. We used functional magnetic resonance imaging (fMRI) to study pain sensitization in patients with knee osteoarthritis. Sixty patients were recruited and pain sensitization was clinically defined on the basis of regional spreading of pain (spreading sensitization) and increased pain response to repeated stimulation (temporal summation). Functional magnetic resonance imaging testing involved assessing brain responses to both pressure and heat stimulation. Thirty-three patients (55%) showed regional pain spreading (simple sensitization) and 19 patients (32%) showed both regional spreading and temporal summation. Sensitized patients were more commonly women. Direct painful pressure stimulation of the joint (articular interline) robustly activated all of the neural elements typically involved in pain perception, but did not differentiate sensitized and nonsensitized patients. Painful pressure stimulation on the anterior tibial surface (sensitized site) evoked greater activation in sensitized patients in regions typically involved in pain and also beyond these regions, extending to the auditory, visual, and ventral sensorimotor cortices. Painful heat stimulation of the volar forearm did not discriminate the sensitization phenomenon. Results confirm the high prevalence of pain sensitization secondary to knee osteoarthritis. Relevantly, the sensitization phenomenon was associated with neural changes extending beyond strict pain-processing regions with enhancement of activity in general sensory, nonnociceptive brain areas. This effect is in contrast to the changes previously identified in primary pain sensitization in fibromyalgia patients presenting with a weakening of the general sensory integration.
Publisher: Proceedings of the National Academy of Sciences
Date: 15-07-2008
Abstract: The notion of a “default mode of brain function” has taken on certain relevance in human neuroimaging studies and in relation to a network of lateral parietal and midline cortical regions that show prominent activity fluctuations during passive imaging states, such as rest. In this study, we perform three fMRI experiments that demonstrate consistency and specialization in the default mode network. Correlated activity fluctuations of default mode network regions are identified during ( i ) eyes-closed spontaneous rest, ( ii ) activation by moral dilemma, and ( iii ) deactivation by Stroop task performance. Across these imaging states, striking uniformity is shown in the basic anatomy of the default mode network, but with both tasks clearly and differentially modulating this activity compared with spontaneous fluctuations of the network at rest. Against rest, moral dilemma is further shown to evoke regionally specific activity increases of hypothesized functional relevance. Mapping spontaneous and task-related brain activity will help to constrain the meaning of the default mode network. These findings are discussed in relation to recent debate on the topic of default modes of brain function.
Publisher: Royal College of Psychiatrists
Date: 2014
DOI: 10.1192/BJP.BP.112.123364
Abstract: Despite knowledge of amygdala involvement in fear and anxiety, its contribution to the pathophysiology of obsessive–compulsive disorder (OCD) remains controversial. In the context of neuroimaging studies, it seems likely that the heterogeneity of the disorder might have contributed to a lack of consistent findings. To assess the influence of OCD symptom dimensions on amygdala responses to a well-validated emotional face-matching paradigm. Cross-sectional functional magnetic resonance imaging (fMRI) study of 67 patients with OCD and 67 age-, gender- and education-level matched healthy controls. The severity of aggression/checking and sexual/religious symptom dimensions were significantly associated with heightened amygdala activation in those with OCD when responding to fearful faces, whereas no such correlations were seen for other symptom dimensions. Amygdala functional alterations in OCD appear to be specifically modulated by symptom dimensions whose origins may be more closely linked to putative amygdala-centric processes, such as abnormal fear processing.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 31-08-2017
DOI: 10.1097/J.PAIN.0000000000000707
Abstract: Patients with fibromyalgia (FM) show characteristically enhanced unpleasantness to painful and nonpainful sensations accompanied by altered neural responses. The diagnostic potential of such neural alterations, including their sensitivity and specificity to FM (vs healthy controls) is unknown. We identify a brain signature that characterizes FM central pathophysiology at the neural systems level. We included 37 patients with FM and 35 matched healthy controls, and analyzed functional magnetic resonance imaging responses to (1) painful pressure and (2) nonpainful multisensory (visual–auditory–tactile) stimulation. We used machine-learning techniques to identify a brain-based FM signature. When exposed to the same painful stimuli, patients with FM showed greater neurologic pain signature (NPS Wager et al., 2013. An fMRI-based neurologic signature of physical pain. N Engl J Med 2013 :1388–97) responses. In addition, a new pain-related classifier (“FM-pain”) revealed augmented responses in sensory integration (insula/operculum) and self-referential (eg, medial prefrontal) regions in FM and reduced responses in the lateral frontal cortex. A “multisensory” classifier trained on nonpainful sensory stimulation revealed augmented responses in the insula/operculum, posterior cingulate, and medial prefrontal regions and reduced responses in the primary/secondary sensory cortices, basal ganglia, and cerebellum. Combined activity in the NPS, FM pain, and multisensory patterns classified patients vs controls with 92% sensitivity and 94% specificity in out-of-s le in iduals. Enhanced NPS responses partly mediated mechanical hypersensitivity and correlated with depression and disability ( P uncorrected 0.05) FM-pain and multisensory responses correlated with clinical pain ( P uncorrected 0.05). The study provides initial characterization of in idual patients with FM based on pathophysiological, symptom-related brain features. If replicated, these brain features may constitute objective neural targets for therapeutic interventions. The results establish a framework for assessing therapeutic mechanisms and predicting treatment response at the in idual level.
Publisher: Wiley
Date: 24-11-2016
DOI: 10.1002/HBM.22905
Publisher: Wiley
Date: 14-01-2013
DOI: 10.1111/ADB.12027
Abstract: Neuroimaging studies have shown that chronic consumption of cannabis may result in alterations in brain morphology. Recent work focusing on the relationship between brain structure and the catechol-O-methyltransferase (COMT) gene polymorphism suggests that functional COMT variants may affect brain volume in healthy in iduals and in schizophrenia patients. We measured the influence of COMT genotype on the volume of four key regions: the prefrontal cortex, neostriatum (caudate-putamen), anterior cingulate cortex and hippoc us-amygdala complex, in chronic early-onset cannabis users and healthy control subjects. We selected 29 chronic cannabis users who began using cannabis before 16 years of age and matched them to 28 healthy volunteers in terms of age, educational level and IQ. Participants were male, Caucasians aged between 18 and 30 years. All were assessed by a structured psychiatric interview (PRISM) to exclude any lifetime Axis-I disorder according to Diagnostic and Statistical Manual for Mental Disorders-Fourth Edition. COMT genotyping was performed and structural magnetic resonance imaging data was analyzed by voxel-based morphometry. The results showed that the COMT polymorphism influenced the volume of the bilateral ventral caudate nucleus in both groups, but in an opposite direction: more copies of val allele led to lesser volume in chronic cannabis users and more volume in controls. The opposite pattern was found in left amygdala. There were no effects of COMT genotype on volumes of the whole brain or the other selected regions. Our findings support recent reports of neuroanatomical changes associated with cannabis use and, for the first time, reveal that these changes may be influenced by the COMT genotype.
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.BIOPSYCH.2014.03.007
Abstract: Psychopathy is characterized by a distinctive interpersonal style that combines callous-unemotional traits with inflexible and antisocial behavior. Traditional emotion-based perspectives link emotional impairment mostly to alterations in amygdala-ventromedial frontal circuits. However, these models alone cannot explain why in iduals with psychopathy can regularly benefit from emotional information when placed on their focus of attention and why they are more resistant to interference from nonaffective contextual cues. The present study aimed to identify abnormal or distinctive functional links between and within emotional and cognitive brain systems in the psychopathic brain to characterize further the neural bases of psychopathy. High-resolution anatomic magnetic resonance imaging with a functional sequence acquired in the resting state was used to assess 22 subjects with psychopathy and 22 control subjects. Anatomic and functional connectivity alterations were investigated first using a whole-brain analysis. Brain regions showing overlapping anatomic and functional changes were examined further using seed-based functional connectivity mapping. Subjects with psychopathy showed gray matter reduction involving prefrontal cortex, paralimbic, and limbic structures. Anatomic changes overlapped with areas showing increased degree of functional connectivity at the medial-dorsal frontal cortex. Subsequent functional seed-based connectivity mapping revealed a pattern of reduced functional connectivity of prefrontal areas with limbic-paralimbic structures and enhanced connectivity within the dorsal frontal lobe in subjects with psychopathy. Our results suggest that a weakened link between emotional and cognitive domains in the psychopathic brain may combine with enhanced functional connections within frontal executive areas. The identified functional alterations are discussed in the context of potential contributors to the inflexible behavior displayed by in iduals with psychopathy.
Publisher: Elsevier BV
Date: 04-2010
DOI: 10.1016/J.NEUROIMAGE.2010.01.031
Abstract: The lateral surface of the right frontal lobe has a relevant role in modulating behavioral responses to aversive stimuli and may significantly influence pain experience. Imaging studies suggest that this modulatory role is multifaceted, but no studies have assessed the regional specialization of this cortex on the basis of its response dynamics during pain processing. We aimed to investigate functional specialization within the right lateral frontal cortex using a dynamic fMRI approach. Brain responses to a mechanical painful stimulus and a preceding anticipatory cue (auditory tone) were assessed in 25 healthy subjects. Functional data were decomposed into 15 sequential activation maps covering the full anticipation-painful stimulation cycle using a finite impulse response (FIR) analysis approach. Movie sequences showing the temporal evolution of brain activation illustrate the findings. A region involving premotor-prefrontal cortices was activated soon after the anticipatory cue and showed a significant correlation with both anterior cingulate cortex activation and subjective pain ratings. The frontal operculum also showed a significant anticipatory response, but the most robust activation followed painful stimulation onset and was strongly correlated with insula activation. The anterior prefrontal cortex showed full activation during late painful stimulation and was negatively correlated with pain unpleasantness. In conclusion, different elements within the right lateral frontal cortex showed distinct activation dynamics in response to painful stimulation, which would suggest relevant regional specialization during pain processing. These findings are congruent with the broad functional role of the right frontal cortex and its influence on crucial aspects of human behavior.
Publisher: Cambridge University Press (CUP)
Date: 21-01-2009
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 16-02-2022
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2014
DOI: 10.1016/J.PAIN.2014.04.028
Abstract: Fibromyalgia typically presents with spontaneous body pain with no apparent cause and is considered pathophysiologically to be a functional disorder of somatosensory processing. We have investigated potential associations between the degree of self-reported clinical pain and resting-state brain functional connectivity at different levels of putative somatosensory integration. Resting-state functional magnetic resonance imaging was obtained in 40 women with fibromyalgia and 36 control subjects. A combination of functional connectivity-based measurements were used to assess (1) the basic pain signal modulation system at the level of the periaqueductal gray (PAG) (2) the sensory cortex with an emphasis on the parietal operculum/secondary somatosensory cortex (SII) and (3) the connectivity of these regions with the self-referential "default mode" network. Compared with control subjects, a reduction of functional connectivity was identified across the 3 levels of neural processing, each showing a significant and complementary correlation with the degree of clinical pain. Specifically, self-reported pain in fibromyalgia patients correlated with (1) reduced connectivity between PAG and anterior insula (2) reduced connectivity between SII and primary somatosensory, visual, and auditory cortices and (3) increased connectivity between SII and the default mode network. The results confirm previous research demonstrating abnormal functional connectivity in fibromyalgia and show that alterations at different levels of sensory processing may contribute to account for clinical pain. Importantly, reduced functional connectivity extended beyond the somatosensory domain and implicated visual and auditory sensory modalities. Overall, this study suggests that a general weakening of sensory integration underlies clinical pain in fibromyalgia.
Publisher: Public Library of Science (PLoS)
Date: 21-04-2009
Publisher: Elsevier BV
Date: 02-2011
DOI: 10.1016/J.BIOPSYCH.2010.07.029
Abstract: Whole-brain imaging approaches may contribute to the characterization of neuroanatomic alterations in major depression, especially in clinically homogenous patient groups such as those with melancholic features. We assessed brain anatomic alterations, both cross-sectionally and longitudinally, in patients with melancholic depression using a whole-brain voxel-wise approach. Whole-brain magnetic resonance images were collected from a relatively aged s le of 70 consecutively recruited major depressive disorder inpatients with melancholic features and from a group of 40 healthy control subjects. All patients were clinically followed for at least 2 years, and a subset of 30 depressive patients and 20 control subjects were rescanned after a 7-year period. Imaging data were analyzed with voxel- and tensor-based morphometry techniques. Melancholic patients showed gray matter reductions in the left insula and white matter increases in the upper brainstem tegmentum. Male patients showed gray matter decreases in the right thalamus, and periventricular white matter reductions were specifically observed in older patients. Volume decreases in the left insula, hippoc us, and lateral parietal cortex predicted a slower recovery after treatment initiation. In longitudinal assessment, white matter of the upper brainstem tegmentum showed a different temporal evolution between groups. Additionally, bilateral gray matter reductions in the insulae were associated with the number of relapses during follow-up. Structural alterations were identified in regions potentially related to relevant aspects of melancholia pathophysiology. Longitudinal analyses indicated region-specific interactions of baseline alterations with age as well as a significant association of clinical severity with focal changes occurring over time.
Publisher: Cambridge University Press (CUP)
Date: 16-08-2012
DOI: 10.1017/S0033291712001857
Abstract: Distorted images of the observable self are considered crucial in the development and maintenance of social anxiety. We generated an experimental situation in which participants viewed themselves from an observer's perspective when exposed to scrutiny and evaluation by others. Twenty patients with social anxiety disorder (SAD) and 20 control subjects were assessed using functional magnetic resonance imaging (fMRI) during the public exposure of pre-recorded videos in which they were each shown performing a verbal task. The examiners acted as the audience in the experiment and rated performance. Whole-brain functional maps were computed using Statistical Parametric Mapping. Robust activation was observed in regions related to self-face recognition, emotional response and general arousal in both study groups. Patients showed significantly greater activation only in the primary visual cortex. By contrast, they showed significant deactivation or smaller activation in dorsal frontoparietal and anterior cingulate cortices relevant to the cognitive control of negative emotion. Task-related anxiety ratings revealed a pattern of negative correlation with activation in this frontoparietal/cingulate network. Importantly, the relationship between social anxiety scores and neural response showed an inverted-U function with positive correlations in the lower score range and negative correlations in the higher range. Our findings suggest that exposure to scrutiny and evaluation in SAD may be associated with changes in cortical systems mediating the cognitive components of anxiety. Disorder severity seems to be relevant in shaping the neural response pattern, which is distinctively characterized by a reduced cortical response in the most severe cases.
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.SEMARTHRIT.2017.06.005
Abstract: The purpose of this systematic review is to systematically review the evidence relating to findings generated by multivariate pattern analysis (MVPA) following structural or functional magnetic resonance imaging (fMRI) to determine if this analysis is able to: a) Discriminate between in iduals with musculoskeletal pain and healthy controls, b) Predict pain perception in healthy in iduals stimulated with a noxious stimulus compared to those stimulated with a non-noxious stimulus. MEDLINE, CINAHL, Embase, PEDro, Google Scholar, Cochrane library and Web of Science were systematically screened for relevant literature using different combinations of keywords regarding structural and functional MRI analysed with MVPA, both in in iduals with musculoskeletal pain and healthy controls. Reference lists of included articles were hand-searched for additional literature. Eligible articles were assessed on risk of bias and reviewed by two independent researchers. The search query returned 18 articles meeting the inclusion criteria. Methodological quality varied from poor to good. Seven studies investigated the ability of machine-learning algorithms to differentiate patient groups from healthy control participants. Overall, the review demonstrated that MVPA can discriminate between in iduals with MSK pain and healthy controls with an overall accuracy ranging from 53% to 94%. Twelve studies utilized healthy control participants (using them as their own controls), during experimental pain paradigms aimed to investigate the ability of machine-learning to differentiate in iduals stimulated with noxious stimuli from those stimulated with non-noxious stimuli, with 'pain' detection rates ranging from 60% to 94%. However, significant heterogeneity in patient conditions, study methodology and brain imaging techniques resulted in various findings that make study comparisons and formal conclusions challenging. There is preliminary and emerging evidence that MVPA analyses of structural or functional MRI are able to discriminate between patients and healthy controls, and also discriminate between noxious and non-noxious stimulation. No prospective studies were found in this review to allow determination of the prognostic or diagnostic capabilities or treatment responsiveness of these analyses. Future studies would also benefit from combining various behavioural, genotype and phenotype data into analyses to assist with development of sensitive and specific signatures that could guide future in idualized patient treatment options and evaluate how treatments exert their effects.
Publisher: Public Library of Science (PLoS)
Date: 29-07-2011
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.JPSYCHIRES.2013.12.008
Abstract: Recreational drugs are generally used to intentionally alter conscious experience. Long-lasting cannabis users frequently seek this effect as a means to relieve negative affect states. As with conventional anxiolytic drugs, however, changes in subjective feelings may be associated with memory impairment. We have tested whether the use of cannabis, as a psychoactive compound, is associated with alterations in spontaneous activity in brain networks relevant to self-awareness, and whether such potential changes are related to perceived anxiety and memory performance. Functional connectivity was assessed in the Default and Insula networks during resting state using fMRI in 28 heavy cannabis users and 29 control subjects. Imaging assessments were conducted during cannabis use in the unintoxicated state and repeated after one month of controlled abstinence. Cannabis users showed increased functional connectivity in the core of the Default and Insula networks and selective enhancement of functional anticorrelation between both. Reduced functional connectivity was observed in areas overlapping with other brain networks. Observed alterations were associated with behavioral measurements in a direction suggesting anxiety score reduction and interference with memory performance. Alterations were also related to the amount of cannabis used and partially persisted after one month of abstinence. Chronic cannabis use was associated with significant effects on the tuning and coupling of brain networks relevant to self-awareness, which in turn are integrated into brain systems supporting the storage of personal experience and motivated behavior. The results suggest potential mechanisms for recreational drugs to interfere with higher-order network interactions generating conscious experience.
Publisher: Elsevier BV
Date: 02-2013
DOI: 10.1016/J.BIOPSYCH.2012.10.006
Abstract: Functional neuroimaging studies have provided consistent support for the idea that obsessive-compulsive disorder (OCD) is associated with disturbances of brain corticostriatal systems. However, in general, these studies have not sought to account for the disorder's prominent clinical heterogeneity. To address these concerns, we investigated the influence of major OCD symptom dimensions on brain corticostriatal functional systems in a large s le of OCD patients (n = 74) and control participants (n = 74) examined with resting-state functional magnetic resonance imaging. We employed a valid method for mapping ventral and dorsal striatal functional connectivity, which supported both standard group comparisons and linear regression analyses with patients' scores on the Dimensional Yale-Brown Obsessive-Compulsive Scale. Consistent with past findings, patients demonstrated a common connectivity alteration involving the ventral striatum and orbitofrontal cortex that predicted overall illness severity levels. This common alteration was independent of the effect of particular symptom dimensions. Instead, we observed distinct anatomical relationships between the severity of symptom dimensions and striatal functional connectivity. Aggression symptoms modulated connectivity between the ventral striatum, amygdala, and ventromedial frontal cortex, while sexual/religious symptoms had a specific influence on ventral striatal-insular connectivity. Hoarding modulated the strength of ventral and dorsal striatal connectivity with distributed frontal regions. Taken together, these results suggest that pathophysiological changes among orbitofrontal-striatal regions may be common to all forms of OCD. They suggest that a further examination of certain dimensional relationships will also be relevant for advancing current neurobiological models of the disorder.
Publisher: American Medical Association (AMA)
Date: 07-2012
DOI: 10.1001/ARCHGENPSYCHIATRY.2011.2165
Abstract: Heightened moral sensitivity seems to characterize patients with obsessive-compulsive disorder (OCD). Recent advances in social cognitive neuroscience suggest that a compelling relationship may exist between this disorder-relevant processing bias and the functional activity of brain regions implicated in OCD. To test the hypothesis that patients with OCD demonstrate an increased response of relevant ventromedial prefrontal and orbitofrontal cortex regions in a functional magnetic resonance imaging study of difficult moral decision making. Case-control cross-sectional study. Hospital referral OCD unit and magnetic resonance imaging facility. Seventy-three patients with OCD (42 men and 31 women) and 73 control participants matched for age, sex, and education level. Functional magnetic resonance imaging activation maps representing significant changes in blood oxygenation level-dependent signal in response to 24 hypothetical moral dilemma vs nondilemma task vignettes and additional activation maps representing significant linear associations between patients' brain responses and symptom severity ratings. In both groups, moral dilemma led to robust activation of frontal and temporoparietal brain regions. Supporting predictions, patients with OCD demonstrated significantly increased activation of the ventral frontal cortex, particularly of the medial orbitofrontal cortex. In addition, the left dorsolateral prefrontal cortex and left middle temporal gyrus were more robustly activated in patients with OCD. These results were unexplained by group differences in comorbid affective symptoms. Patients' global illness severity predicted the relative magnitude of orbitofrontal-striatal activation. The severity of "harm/checking" symptoms and "sexual/religious" obsessions predicted the magnitude of posterior temporal and amygdala-paralimbic activation, respectively. The neural correlates of moral sensitivity in patients with OCD partly coincide with brain regions that are of general interest to pathophysiologic models of this disorder. In particular, these findings suggest that the orbitofrontal cortex together with the left dorsolateral prefrontal cortex may be relevant for understanding the link between neurobiological processes and certain maladaptive cognitions in OCD.
Publisher: Public Library of Science (PLoS)
Date: 28-06-2012
Publisher: Wiley
Date: 06-07-2010
DOI: 10.1002/HBM.21094
Publisher: Wiley
Date: 06-07-2015
DOI: 10.1002/HBM.22889
Publisher: Informa UK Limited
Date: 25-07-2011
DOI: 10.3109/15622975.2011.559268
Abstract: OBJECTIVES. The abnormal processing of emotional stimuli is common to a variety of psychiatric disorders. Specifically, patients with prominent anxiety symptoms generally overreact to emotional cues, which has been linked to increased amygdala activation. However, in OCD, enhanced responses are predominantly obtained using disease-specific stimuli and preferentially involve frontostriatal systems. METHODS. We assessed 21 OCD patients and 21 healthy controls with fMRI during an emotional face-processing paradigm involving active response generation to test for alterations in both brain activation and task-induced functional connectivity of the frontal cortex, the amygdala and the fusiform face area. RESULTS. OCD patients showed significantly greater activation of "face-processing" regions including the amygdala, fusiform gyrus and dorsolateral prefrontal cortex. The reciprocal connectivity between face-processing regions was enhanced in OCD. Importantly, we detected significant correlations between patients' clinical symptom severity and both task-related region activation and network functional connectivity. CONCLUSIONS. The results suggest that OCD patients may show enhanced brain responsiveness during emotional face-processing when tasks involve active response generation. Our findings erge from previously described alterations in anxiety disorders, as patients showed enhanced amygdala-prefrontal connectivity as opposed to negative reciprocal interaction. This pattern would appear to be disorder-specific and was significantly related to obsessive-compulsive symptom severity.
Publisher: Oxford University Press (OUP)
Date: 05-02-2013
DOI: 10.1093/SCAN/NST014
Publisher: Wiley
Date: 26-10-2014
DOI: 10.1002/ART.38781
Publisher: Springer Science and Business Media LLC
Date: 28-07-2010
DOI: 10.1038/NPP.2010.108
Publisher: Oxford University Press (OUP)
Date: 27-10-2011
DOI: 10.1093/SCAN/NSR075
Publisher: American Medical Association (AMA)
Date: 11-2009
DOI: 10.1001/ARCHGENPSYCHIATRY.2009.152
Abstract: Neurobiological models of obsessive-compulsive disorder (OCD) emphasize disturbances in the function and connectivity of brain corticostriatal networks, or "loops." Although neuroimaging studies of patients have supported this network model of OCD, very few have applied measurements that are sensitive to brain connectivity features. Using resting-state functional magnetic resonance imaging, we tested the hypothesis that OCD is associated with disturbances in the functional connectivity of primarily ventral corticostriatal regions, measured from coherent spontaneous fluctuations in the blood oxygenation level-dependent (BOLD) signal. Case-control cross-sectional study. Hospital referral OCD unit and magnetic resonance imaging facility. A total of 21 patients with OCD (10 men, 11 women) and 21 healthy control subjects matched for age, sex, and estimated intelligence. Voxelwise statistical parametric maps testing the strength of functional connectivity of 4 striatal seed regions of interest (dorsal caudate nucleus, ventral caudate/nucleus accumbens, dorsal putamen, and ventral putamen) with remaining brain areas. For both groups, there was a clear distinction in the pattern of cortical connectivity of dorsal and ventral striatal regions, consistent with the notion of segregated motor, associative, and limbic corticostriatal networks. Between groups, patients with OCD had significantly increased functional connectivity along a ventral corticostriatal axis, implicating the orbitofrontal cortex and surrounding areas. The specific strength of connectivity between the ventral caudate/nucleus accumbens and the anterior orbitofrontal cortex predicted patients' overall symptom severity (r(2) = 0.57 P < .001). Additionally, patients with OCD showed evidence of reduced functional connectivity of the dorsal striatum and lateral prefrontal cortex, and of the ventral striatum with the region of the midbrain ventral tegmental area. This study directly supports the hypothesis that OCD is associated with functional alterations of brain corticostriatal networks. Specifically, our findings emphasize abnormal and heightened functional connectivity of ventrolimbic corticostriatal regions in patients with OCD.
Publisher: Springer New York
Date: 2012
No related grants have been discovered for MARINA LOPEZ SOLA.