Suchergebnisse

There is ample evidence from basic research in neuroscience of the importance of local corticocortical networks. Millimetric resolution is achievable with current functional magnetic resonance imaging (fMRI) scanners and sequences, and consequently a number of "local" activity similarity measures have been defined to describe patterns of segregation and integration at this spatial scale. We have introduced the use of IsoDistant Average Correlation (IDAC), easily defined as the average fMRI temporal correlation of a given voxel with other voxels placed at increasingly separated isodistant intervals, to characterize the curve of local fMRI signal similarities. IDAC curves can be statistically compared using parametric multivariate statistics. Furthermore, by using red-green-blue color coding to display jointly IDAC values belonging to three different distance lags, IDAC curves can also be displayed as multidistance IDAC maps. We applied IDAC analysis to a sample of 41 subjects scanned under two different conditions, a resting state and an auditory-visual continuous stimulation. Multidistance IDAC mapping was able to discriminate between gross anatomofunctional cortical areas and, moreover, was sensitive to modulation between the two brain conditions in areas known to activate and deactivate during audiovisual tasks. Unlike previous fMRI local similarity measures already in use, our approach draws special attention to the continuous smooth pattern of local functional connectivity. ; This work was supported in part by the Carlos III Health Institute grant PI10/02206 and the I+D+I grant PSI2014-53524-P. We thank the Agency of University and Research Funding Management of the Catalonia Government for their participation in the context of Research Group SGR SGR2017-1198.

Introduction: Children are more vulnerable to the effects of environmental elements. A variety of air pollutants are among the identified factors causing neural damage at toxic concentrations. It is not obvious, however, to what extent the tolerated high levels of air pollutants are able to alter brain development. We have specifically investigated the neurotoxic effects of airborne copper exposure in school environments. Methods: Speed and consistency of motor response were assessed in 2836 children aged from 8 to 12 years. Anatomical MRI, diffusion tensor imaging, and functional MRI were used to directly test the brain repercussions in a subgroup of 263 children. Results: Higher copper exposure was associated with poorer motor performance and altered structure of the basal ganglia. Specifically, the architecture of the caudate nucleus region was less complete in terms of both tissue composition and neural track water diffusion. Functional MRI consistently showed a reciprocal connectivity reduction between the caudate nucleus and the frontal cortex. Conclusions: The results establish an association between environmental copper exposure in children and alterations of basal ganglia structure and function. © 2016 The Authors. Brain and Behavior published by Wiley Periodicals, Inc. ; This work was supported by the European Research Council under the ERC (grant number 268479) ?the BREATHE project. The Agency of University and Research Funding Management of the Catalonia Government participated in the context of Research Group SGR2014-1673. We acknowledge C. Persavento, J. Gonz?lez, L. Bouso, M. L?pez, and P. Figueras their contribution to the field work. We also acknowledge all the families and schools participating in the study. ; Peer reviewed

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. ; This study was supported in part by the Ministry of Economy and Competitiveness of Spain (grant PSI2014- 53524-P) and the Merck Investigator Studies Program (grant MISP-IISP41059). We thank to the Agency of University and Research Funding Management of the Catalonia Government for their participation in the context of Research Group SGR2014-1673. BJH is supported by a National Health and Medical Research Council of Australia (NHMRC) Clinical Career Development Award (1124472).

INTRODUCTION: Children are more vulnerable to the effects of environmental elements. A variety of air pollutants are among the identified factors causing neural damage at toxic concentrations. It is not obvious, however, to what extent the tolerated high levels of air pollutants are able to alter brain development. We have specifically investigated the neurotoxic effects of airborne copper exposure in school environments. METHODS: Speed and consistency of motor response were assessed in 2836 children aged from 8 to 12 years. Anatomical MRI, diffusion tensor imaging, and functional MRI were used to directly test the brain repercussions in a subgroup of 263 children. RESULTS: Higher copper exposure was associated with poorer motor performance and altered structure of the basal ganglia. Specifically, the architecture of the caudate nucleus region was less complete in terms of both tissue composition and neural track water diffusion. Functional MRI consistently showed a reciprocal connectivity reduction between the caudate nucleus and the frontal cortex./nCONCLUSIONS: The results establish an association between environmental copper exposure in children and alterations of basal ganglia structure and function. ; This work was supported by the European Research Council under the ERC (grant number 268479)—the BREATHE project. The Agency of University and Research Funding Management of the Catalonia Government participated in the context of Research Group SGR2014-1673.

Objective: Sluggish cognitive tempo (SCT) is a cluster of symptoms associated with poor function in various domains of major life activities that may comprise a novel attention disorder distinct from attention-deficit/hyperactivity disorder (ADHD). Nevertheless, very little is known about the neural substrate of SCT in children. The present study aimed to examine associations between SCT symptoms and brain structure and function in school-aged children. Method: We performed a cross-sectional MRI study in 178 children 8 to 12 years old from primary schools in Barcelona, Spain. Data were collected between January 2012 and March 2013. Parents completed the Sluggish Cognitive Tempo-Child Behavior Checklist (SCT-CBCL). Participants underwent magnetic resonance imaging to assess regional brain volume, white matter integrity using diffusion tensor imaging, and functional connectivity in major neural networks. Results: SCT symptoms were associated with altered anatomy of the frontal lobe in the form of increased regional volume. The anomalously large cortical regions were less mature in terms of functional connectivity. Importantly, all the anatomical and functional anomalies identified remained significant after adjusting the analyses for ADHD symptom scores. Conclusion: Our results suggest that SCT symptoms are associated with distinct features of brain structure and function that differ from the classical neural substrates described in ADHD. ; This work was supported by the European Research Council under the ERC (grant number 268479)—the BREATHE project. The Agency of University and Research Funding Management of the Catalonia Government part icipated in the context of Research Group SGR2014-167

INTRODUCTION: Knee osteoarthritis is causing pain and functional disability. One of the inherent problems with efficacy assessment of pain medication was the lack of objective pain measurements, but functional magnetic resonance imaging (fMRI) has emerged as a useful means to objectify brain response to painful stimulation. We have investigated the effect of chondroitin sulfate (CS) on brain response to knee painful stimulation in patients with knee osteoarthritis using fMRI. METHODS: Twenty-two patients received CS (800mg/day) and 27 patients placebo, and were assessed at baseline and after 4 months of treatment. Two fMRI tests were conducted in each session by applying painful pressure on the knee interline and on the patella surface. The outcome measurement was attenuation of the response evoked by knee painful stimulation in the brain. RESULTS: fMRI of patella pain showed significantly greater activation reduction under CS compared with placebo in the region of the mesencephalic periaquecductal gray. The CS group, additionally showed pre/post-treatment activation reduction in the cortical representation of the leg. No effects of CS were detected using the interline pressure test. CONCLUSIONS: fMRI was sensitive to objectify CS effects on brain response to painful pressure on patellofemoral cartilage, which is consistent with the known CS action on chondrocyte regeneration. The current work yields further support to the utility of fMRI to objectify treatment effects on osteoarthritis pain. ; This work was supported in part by the Ministry of Science and Innovation of Spain (Grant SAF2010-19434) and by Bioiberica, SA, Barcelona. M. López-Solà and J. Deus are part of the Research Group SGR 1450 from the Agency of University and Research Funding Management of the Catalan Government and M. López-Solà is supported by the post-doctoral fellowship Beatriu de Pinós awarded by the Agency for the Management of University and Research funding (Agència de Gestió d'Ajuts Universitaris i de Recerca; AGAUR), from the Catalan Government (2010 BP_A 00136).

Children are more vulnerable to the effects of environmental elements due to their active developmental processes. Exposure to urban air pollution has been associated with poorer cognitive performance, which is thought to be a result of direct interference with brain maturation. We aimed to assess the extent of such potential effects of urban pollution on child brain maturation using general indicators of vehicle exhaust measured in the school environment and a comprehensive imaging evaluation. A group of 263 children, aged 8 to 12years, underwent MRI to quantify regional brain volumes, tissue composition, myelination, cortical thickness, neural tract architecture, membrane metabolites, functional connectivity in major neural networks and activation/deactivation dynamics during a sensory task. A combined measurement of elemental carbon and NO2 was used as a putative marker of vehicle exhaust. Air pollution exposure was associated with brain changes of a functional nature, with no evident effect on brain anatomy, structure or membrane metabolites. Specifically, a higher content of pollutants was associated with lower functional integration and segregation in key brain networks relevant to both inner mental processes (the default mode network) and stimulus-driven mental operations. Age and performance (motor response speed) both showed the opposite effect to that of pollution, thus indicating that higher exposure is associated with slower brain maturation. In conclusion, urban air pollution appears to adversely affect brain maturation in a critical age with changes specifically concerning the functional domain. ; This work was supported by the European Research Council under the ERC [grant number 268479]—the BREATHE project. The Agency of University and Research Funding Management of the Catalonia Government participated in the context of Research Group SGR2014-1673.