Brain activity during traditional textbook and audiovisual-3D learning

INTRODUCTION: Audiovisual educational tools have increasingly been used during the past years to complement and compete with traditional textbooks. However, little is known as to how the brain processes didactic information presented in different formats. We directly assessed brain activity during learning using both traditional textbook and audiovisual-3D material. METHODS: A homogeneous sample of 30 young adults with active study habits was assessed. Educational material on the subject of Cardiology was adapted to be presented during the acquisition of functional MRI. RESULTS: When tested after image acquisition, participants obtained similar examination scores for both formats. Evoked brain activity was robust during both traditional textbook and audiovisual-3D lessons, but a greater number of brain systems were implicated in the processing of audiovisual-3D information, consistent with its multisource sensory nature. However, learning was not associated with group mean brain activations, but was instead predicted by distinct functional MRI signal changes in the frontal lobes and showed distinct cognitive correlates. In the audiovisual-3D version, examination scores were positively correlated with late-evoked prefrontal cortex activity and working memory, and negatively correlated with language-related frontal areas and verbal memory. As for the traditional textbook version, the fewer results obtained suggested the opposite pattern, with examination scores negatively correlating with prefrontal cortex activity evoked during the lesson. CONCLUSIONS: Overall, the results indicate that a similar level of knowledge may be achieved via different cognitive strategies. In our experiment, audiovisual learning appeared to benefit from prefrontal executive resources (as opposed to memorizing verbal information) more than traditional textbook learning

Dysfunctional brain reward system in child obesity

Eating habits leading to obesity may reflect nonhomeostatic behavior based on excessive immediate-reward seeking. However, it is currently unknown to what extent excess weight is associated with functional alterations in the brain's reward system in children. We tested the integrity of reward circuits using resting-state functional connectivity magnetic resonance imaging in a population of 230 children aged 8-12 years. The major components of the reward system were identified within the ventral striatum network defined on the basis of the nucleus accumbens connectivity pattern. The functional structure of the cerebral cortex was characterized using a combination of local functional connectivity measures. Higher body mass index was associated with weaker connectivity between the cortical and subcortical elements of the reward system, and enhanced the integration of the sensorimotor cortex to superior parietal areas relevant to body image formation. Obese children, unlike WHO-defined overweight condition, showed functional structure alterations in the orbitofrontal cortex and amygdala region similar to those previously observed in primary obsessive-compulsive disorder and Prader-Willi syndrome associated with obsessive eating behavior. Results further support the view that childhood obesity is not simply a deviant habit with restricted physical health consequences but is associated with reward system dysfunction characterizing behavioral control disorders.European Research Council under the ERC [grant number 268479]—the BREATHE project

The Effects of Air Pollution on the Brain: a Review of Studies Interfacing Environmental Epidemiology and Neuroimaging

PURPOSE OF REVIEW: An emerging body of evidence has raised concern regarding the potentially harmful effects of inhaled pollutants on the central nervous system during the last decade. In the general population, traffic-related air pollution (TRAP) exposure has been associated with adverse effects on cognitive, behavior, and psychomotor development in children, and with cognitive decline and higher risk of dementia in the elderly. Recently, studies have interfaced environmental epidemiology with magnetic resonance imaging to investigate in vivo the effects of TRAP on the human brain. The aim of this systematic review was to describe and synthesize the findings from these studies. The bibliographic search was carried out in PubMed with ad hoc keywords. RECENT FINDINGS: The selected studies revealed that cerebral white matter, cortical gray matter, and basal ganglia might be the targets of TRAP. The detected brain damages could be involved in cognition changes. The effect of TRAP on cognition appears to be biologically plausible. Interfacing environmental epidemiology and neuroimaging is an emerging field with room for improvement. Future studies, together with inputs from experimental findings, should provide more relevant and detailed knowledge about the nature of the relationship between TRAP exposure and cognitive, behavior, and psychomotor disorders observed in the general population.Marion Mortamais is supported by a Marie Skłodowska-Curie Individual Fellowship (H2020-MSCA-IF-2014; EU project 656294)

Interaction between airborne copper exposure and ATP7B polymorphisms on inattentiveness in scholar children

Recent research indicates that airborne copper exposure in scholar children negatively affects brain functioning. These effects are likely to be influenced by the efficiency of copper metabolism, which is partly regulated by the ATPase copper transporting beta (ATP7B) gene. We investigated whether indoor and outdoor airborne copper exposure is differentially associated with child inattentiveness depending on genetic variation within the ATP7B gene in 1645 scholar children from the BREATHE project. Outdoor (courtyard) and indoor (classroom) air pollution levels were measured during class hours in each school. Inattentiveness was assessed through a follow-up with four measurements via the Attentional Network Test (4475 observations). Linear mixed models considering repeated measures were conducted to assess genetic and exposure main and interaction effects. Two interactions were detected indicating that ATP7B-rs1061472 (P for interaction 0.016) and ATP7B-rs1801243 (P for interaction 0.003) polymorphisms modified the association between indoor copper exposure and inattentiveness. Stratified analysis by genotypes revealed that both outdoor and indoor copper exposure increased inattentiveness in rs1061472-CC and rs1801243-CC carriers. These findings suggest that the genetic background promotes the association between airborne copper exposure at school with inattentiveness in children.The research leading to these results has received funding from the European Research Council under the ERC Grant Agreement number 268479- the BREATHE project. S. Alemany thanks the ‘Instituto de Salud Carlos III’ for her postdoctoral grant (CD14/00214). N. Vilor-Tejedor is funded by a pre-doctoral grant from the Agència de Gestió d’Ajuts Universitaris i de Recerca (2015 FI_B 00636) Generalitat de Catalunya

Altered gesture imitation and brain anatomy in adult prader-willi syndrome patients

Objective: To explore motor praxis in adults with Prader-Willi syndrome (PWS) in comparison with a control group of people with intellectual disability (ID) and to examine the relationship with brain structural measurements. Method: Thirty adult participants with PWS and 132 with ID of nongenetic etiology (matched by age, sex, and ID level) were assessed using a comprehensive evaluation of the praxis function, which included pantomime of tool use, imitation of meaningful and meaningless gestures, motor sequencing, and constructional praxis. Results: Results support specific praxis difficulties in PWS, with worse performance in the imitation of motor actions and better performance in constructional praxis than ID peers. Compared with both control groups, PWS showed increased gray matter volume in sensorimotor and subcortical regions. However, we found no obvious association between these alterations and praxis performance. Instead, praxis scores correlated with regional volume measures in distributed apparently normal brain areas. Conclusions: Our findings are consistent in showing significant impairment in gesture imitation abilities in PWS and, otherwise, further indicate that the visuospatial praxis domain is relatively preserved. Praxis disability in PWS was not associated with a specific, focal alteration of brain anatomy. Altered imitation gestures could, therefore, be a consequence of widespread brain dysfunction. However, the specific contribution of key brain structures (e.g., areas containing mirror neurons) should be more finely tested in future research

Cerebellar dysfunction in adults with prader Willi syndrome

Severe hypotonia during infancy is a hallmark feature of Prader Willi syndrome (PWS). Despite its transient expression, moto development is delayed and deficiencies in motor coordination are present at older ages, with no clear pathophysiological mechanism yet identified. The diverse motor coordination symptoms present in adult PWS patients could be, in part, the result of a common alteration(s) in basic motor control systems. We aimed to examine the motor system in PWS using functional MRI (fMRI) during motor challenge. Twenty-three adults with PWS and 22 matched healthy subjects participated in the study. fMRI testing involved three hand motor tasks of different complexity. Additional behavioral measurements of motor function were obtained by evaluating hand grip strength, functional mobility, and balance. Whole brain activation maps were compared between groups and correlated with behavioral measurements. Performance of the motor tasks in PWS engaged the neural elements typically involved in motor processing. While our data showed no group differences in the simplest task, increasing task demands evoked significantly weaker activation in patients in the cerebellum. Significant interaction between group and correlation pattern with measures of motor function were also observed. Our study provides novel insights into the neural substrates of motor control in PWS by demonstrating reduced cerebellar activation during movement coordination

Brain imaging of pain sensitization in patients with knee osteoarthritis

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)

Hunger and satiety peptides: is there a pattern to classify patients with prader-Willi syndrome?

Hyperphagia is one of the main problems of patients with Prader-Willi syndrome (PWS) to cope with everyday life. The underlying mechanisms are not yet well understood. Gut-brain hormones are an interrelated network that may be at least partially involved. We aimed to study the hormonal profile of PWS patients in comparison with obese and healthy controls. Thirty adult PWS patients (15 men; age 27.5 ± 8.02 years; BMI 32.4 ± 8.14 kg/m2), 30 obese and 30 healthy controls were studied before and after eating a hypercaloric liquid diet. Plasma brain-derived neurotrophic factor (BDNF), leptin, total and active ghrelin, peptide YY (PYY), pancreatic polypeptide (PP), Glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and amylin were determined at times 0', 30', 60' and 120'. Cluster analysis was used. When considering all peptides together, two clusters were established according to fasting hormonal standardized concentrations. Cluster 1 encompassed most of obese (25/30) and healthy controls (28/30). By contrast, the majority of patients with PWS were located in Cluster 2 (23/27) and presented a similar fasting profile with hyperghrelinemia, high levels of leptin, PYY, GIP and GLP-1, compared to Cluster 1; that may reflect a dysfunction of these hunger/satiety hormones. When peptide behavior over the time was considered, PP concentrations were not sustained postprandially from 60 min onwards in Cluster 2. BDNF and amylin did not help to differentiate the two clusters. Thus, cluster analysis could be a good tool to distinguish and characterize the differences in hormone responses between PWS and obese or healthy controls

Strategies for integrated analysis in imaging genetics studies

Imaging Genetics (IG) integrates neuroimaging and genomic data from the same individual, deepening our knowledge of the biological mechanisms behind neurodevelopmental domains and neurological disorders. Although the literature on IG has exponentially grown over the past years, the majority of studies have mainly analyzed associations between candidate brain regions and individual genetic variants. However, this strategy is not designed to deal with the complexity of neurobiological mechanisms underlying behavioral and neurodevelopmental domains. Moreover, larger sample sizes and increased multidimensionality of this type of data represents a challenge for standardizing modeling procedures in IG research. This review provides a systematic update of the methods and strategies currently used in IG studies, and serves as an analytical framework for researchers working in this field. To complement the functionalities of the Neuroconductor framework, we also describe existing R packages that implement these methodologies. In addition, we present an overview of how these methodological approaches are applied in integrating neuroimaging and genetic data.Natalia Vilor-Tejedor was funded by a pre-doctoral grant from theAgència de Gestió d’Ajuts Universitaris i de Recerca (2017 FI_B 00636),Generalitatde Catalunya–Fons Social Europeu. This work has beenpartially supported by a STSM Grant from EU COST Action 15120 OpenMultiscale Systems Medicine (OpenMultiMed) and Centro deInvestigación Biomédica en Red de Epidemiología y Salud Pública(CIBERESP). Silvia Alemany thanks the Institute of Health Carlos III forher Sara Borrell postdoctoral grant (CD14/00214). The researchleading to these results has also received funding from the EuropeanResearch Council under the ERC Grant Agreement number 268479–the BREATHE project and by grant MTM2015-68140-R from theMinisterio de Economía e Innovación (Spain). ISGlobal is a member ofthe CERCA Programme, Generalitat de Catalunya

Airborne copper exposure in school environments associated with poorer motor performance and altered basal ganglia.

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