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Aerobic exercise has been shown to impact brain structure and cognition in children and adults. Exercise-induced activation of a growth protein known as brain derived neurotrophic factor (BDNF) is thought to contribute to such relationships. To date, however, no study has examined how aerobic fitness relates to cortical brain structure during development and if BDNF genotype moderates these relationships. Using structural magnetic resonance imaging (MRI) and FreeSurfer, the current study examined how aerobic fitness relates to volume, thickness, and surface area in 34 male adolescents, 15 to 18 years old. Moreover, we examined if the val66met BDNF genotype moderated these relationships. We hypothesized that aerobic fitness would relate to greater thickness and volumes in frontal, parietal, and motor regions, and that these relationships would be less robust in individuals carrying a Met allele, since this genotype leads to lower BDNF expression. We found that aerobic fitness positively related to right rostral middle frontal cortical volume in all adolescents. However, results also showed BDNF genotype moderated the relationship between aerobic fitness and bilateral medial precuneus surface area, with a positive relationship seen in individuals with the Val/Val allele, but no relationship detected in those adolescents carrying a Met allele. Lastly, using self-reported levels of aerobic activity, we found that higher-fit adolescents showed larger right medial pericalcarine, right cuneus and left precuneus surface areas as compared to their low-fit peers. Our findings suggest that aerobic fitness is linked to cortical brain development in male adolescents, and that more research is warranted to determine how an individual’s genes may influence these relationships.

Abstract Purpose To study clinical profile, neurodevelopmental outcome and its predictors in children with acute symptomatic seizures (ASS). Methods Short-term neurodevelopmental outcome and predictors of poor outcomes were prospectively assessed in 105 consecutive children with ASS aged 3 months-12 years Results Mean age was 51.2+42.2months (3–144 months); 67.2% were males. Central nervous system (CNS) infection in 82%, status epilepticus in 15.2%, abnormal neuroimaging in 62.8% and abnormal electroencephalography in 22.3% were noted. At discharge, 27.6% had poor outcome including death (13%); CNS infections were significantly associated with poor outcome compared to ASS of other aetiologies (32.6% vs 5.2%, p=0.02). Low GCS (OR 4.9, 95%CI 1.2–20.7), abnormal electroencephalograph (OR 4.3, 95%CI 1–16.9) and neuroimaging (OR 12.1, 95%CI 1.4–105.2) were independent predictors of poor outcome. After 6 months, 16% children had delayed neurodevelopment and cognition; 6% had seizure recurrences. Abnormal electroencephalograph (p=0.002; OR 6.8, 95%CI 2.0–23.1), abnormal neuroimaging (p=0.015; OR 9.47, 95%CI 1.18–75.8),>1 anti-epileptic (p=0.00; OR 9.9, 95%CI 2.88–33.9), intubation (p=0.004; OR 6.25, 95%CI 1.79–21.7) and poor outcome at discharge (p=0.02; OR 4.44, 95%CI1.38–14.2) predicted abnormal neurodevelopment. Conclusions CNS infections are the most common cause of ASS in children from developing countries. Abnormal neurodevelopment and seizure recurrences on short-term follow-up are seen in a minority of children.

SummaryIntroductionRespiratory events occurring under non-invasive ventilation (NIV) may produce sleep fragmentation. Alternatives to polysomnography (PSG) should be validated for providing simple monitoring tools for patients treated at home with NIV.ObjectivesTo study the value of pulse wave amplitude (PWA) reduction as a surrogate marker of cortical micro-arousals associated with respiratory events occurring during NIV.Methods27 PSG tracings under NIV recorded in 9 stable patients with Obesity Hypoventilation Syndrome (OHS), under 3 different ventilator modes (no back-up rate, low or high back-up rate) were analyzed. For all respiratory events (obstructive, central, or mixed event), the association with EEG-micro-arousals, PWA reduction of more than 30% and the presence of associated SpO2 desaturation ≥4% was recorded.Results2474 respiratory events during NREM sleep were analyzed. 73.6% were associated with an EEG-MA, 91.4% with a ≥4% decrease in SpO2, and 74.9% with a significant PWA reduction. Sensitivity of PWA for the detection of an EEG-micro-arousal related to a respiratory event was 89.1% [95%CI: 76.7–95.3]. Positive predictive value (PPV) was 87.0% [95%CI: 75.0–94.0]. Sensitivity of PWA was highest in the S mode, compared to both other S/T modes, p = <0.001. Sensitivity of PWA was also higher for central and mixed events, compared to obstructive respiratory events, p = <0.05.ConclusionsPWA reduction is a sensitive marker with a high PPV for the detection of EEG-MA associated with respiratory events during NREM sleep in stable OHS patients treated by NIV. In this situation, PWA could be used to improve scoring of hypopneas and allow an appropriate assessment of sleep fragmentation related to respiratory events.

Diagnosis of the antiphospholipid syndrome (APS) requires that a patient have both a clinical event (thrombosis or pregnancy loss) and persistently positive antiphospholipid antibodies (aPL). Although stroke and transient ischemic attack are the most common neurologic manifestations of APS, both cognitive dysfunction and magnetic resonance imaging (MRI) white matter hyperintensities can occur in aPL-positive patients (with or without APS). Relatively little is known about the cognitive pattern in aPL-positive patients; MRI white matter hyperintensities may be related to underlying attentional and executive cognitive impairment. Studies with sophisticated neuroimaging techniques aimed to better understand MRI white matter hyperintensities may eventually facilitate our understanding of cognitive dysfunction in aPL-positive patients.

Audiovisual speech has a stereotypical rhythm that is between 2 and 7 Hz, and deviations from this frequency range in either modality reduce intelligibility. Understanding how audiovisual speech evolved requires investigating the origins of this rhythmic structure. One hypothesis is that the rhythm of speech evolved through the modification of some pre-existing cyclical jaw movements in a primate ancestor. We tested this hypothesis by investigating the temporal structure of lipsmacks and teeth-grinds of macaque monkeys and the neural responses to these facial gestures in the superior temporal sulcus (STS), a region implicated in the processing of audiovisual communication signals in both humans and monkeys. We found that both lipsmacks and teeth-grinds have consistent but distinct peak frequencies and that both fall well within the 2–7 Hz range of mouth movements associated with audiovisual speech. Single neurons and local field potentials of the STS of monkeys readily responded to such facial rhythms, but also responded just as robustly to yawns, a nonrhythmic but dynamic facial expression. All expressions elicited enhanced power in the delta (0–3Hz), theta (3–8Hz), alpha (8–14Hz) and gamma (> 60 Hz) frequency ranges, and suppressed power in the beta (20–40Hz) range. Thus, STS is sensitive to, but not selective for, rhythmic facial gestures. Taken together, these data provide support for the idea that that audiovisual speech evolved (at least in part) from the rhythmic facial gestures of an ancestral primate and that the STS was sensitive to and thus ‘prepared’ for the advent of rhythmic audiovisual communication.

Alterations in white matter integrity have been well documented in chronic epilepsy and during epileptogenesis. However, the relationship between white matter integrity and a predisposition towards epileptogenesis has been understudied. The FAST rat strain exhibit heightened susceptibility towards kindling epileptogenesis whereas SLOW rats are highly resistant. FAST rats also display behavioral phenotypes reminiscent of those observed in neurodevelopmental disorders that commonly comorbid with epilepsy. In this study, we aim to identify differences in white matter integrity that may contribute to a predisposition towards epileptogenesis and its associated comorbidities in 6 month old FAST (n = 10) and SLOW (n = 10) male rats. Open field and water consumption tests were conducted to confirm the behavioral phenotype difference between FAST and SLOW rats followed by ex-vivo diffusion-weighted magnetic resonance imaging to identify differences in white matter integrity. Diffusion tensor imaging scalar values namely fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity were compared in the anterior commissure, corpus callosum, external capsule, internal capsule, fimbria and optic tract. Electron microscopy was used to evaluate microstructural alterations in myelinated axons. Behavioral phenotyping confirmed higher activity levels (distance moved on days 2–4, p < 0.001; number of rearings on days 2 and 4, p < 0.05 at both days) and polydipsia (p < 0.001) in FAST rats. Comparative analysis of diffusion tensor imaging scalars found a significant decrease in fractional anisotropy in the corpus callosum (p < 0.05) of FAST versus SLOW rats. Using electron microscopy, alterations in myelinated axons including increased axon diameter (p < 0.001) and reduced g-ratio (p < 0.001) in the midline of the corpus callosum in 6 month old FAST (n = 3) versus SLOW (n = 4) male rats. These findings suggest that differences in white matter integrity between FAST and SLOW rats could be a contributing factor to the differential seizure susceptibility and behavioral phenotypes observed in these strains.

BACKGROUND AND PURPOSE: Diffusion-weighted MR imaging studies of the adult brain have shown that contrast between lesions and normal tissue is increased at high b-values. We designed a prospective study to test the hypothesis that diffusion tensor imaging (DTI) obtained at high b-values increases image contrast and lesion conspicuity in the neonatal brain. MATERIALS AND METHODS: We studied 17 neonates, median (range) age of 10 (2–96) days, who were undergoing MR imaging for clinical indications. DTI was performed on a Philips 3T Intera system with b-values of 350, 700, 1500, and 3000 s/mm2. Image contrast and lesion conspicuity at each b-value were visually assessed. In addition, regions of interest were positioned in the central white matter at the level of the centrum semiovale, frontal and occipital white matter, splenium of the corpus callosum, posterior limb of the internal capsule, and the thalamus. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values for these regions were calculated. RESULTS: Isotropic diffusion image contrast and lesion-to-normal-tissue contrast increased with increasing b-value. ADC values decreased with increasing b-value in all regions studied; however, there was no change in FA with increasing b-value. CONCLUSIONS: Diffusion image contrast increased at high b-values may be useful in identifying lesions in the neonatal brain.

To determine structural abnormalities in the brain of patients with schizophrenia by Magnetic Resonance Imaging (MRI).Comparative study.The Departments of Radiology and Psychiatry, the Aga Khan University Hospital, Karachi, from January 2007 to June 2008.Thirty-three cases of schizophrenia (n=33) and thirty-three age-matched controls, (n=33) were enrolled for this study. Screening Magnetic Resonance Imaging (MRI) of brain was done in order to see structural changes in brain matter. Findings were compared among groups using chi-square and Fisher's exact test with significance at p0.05.Among the total of 66 (n=66) MRI films studied for brain abnormalities, brain atrophy, presence of septum pellucidum and enlarged Virchow-Robins spaces were significantly associated with schizophrenia (p0.001). There was no significant difference between cases and controls for ventricular dilatation (p=0.5). Sinusitis was mostly associated with controls and well correlated with their symptoms (p0.001).Brain atrophy was the most commonly seen brain change in the studied sample of patients with schizophrenia. MRI brain can be used to identify structural abnormalities in patients with schizophrenia.

When participants are asked to reproduce an earlier presented duration, EEG recordings typically show a slow potential that develops over the fronto-central regions of the brain and is assumed to be generated in the supplementary motor area (SMA). This contingent negative variation (CNV) has been linked to anticipation, preparation and formation of temporal judgment (Macar, Vidal, and Casini, 1999, Experimental Brain Research, 125(3), 271-80). Although the interpretation of the CNV amplitude is problematic (Kononowicz and Van Rijn, (2011), Frontiers in Integrative Neuroscience, 5(48); Ng, Tobin, and Penney, 2011, Frontiers in Integrative Neuroscience, 5(77)), the observation of this slow potential is extremely robust, and thus one could assume that magnetic recordings of brain activity should show similar activity patterns. However, interval timing studies using durations shorter than one second did not provide unequivocal evidence as to whether CNV has a magnetic counterpart (CMV). As interval timing has been typically associated with durations longer than one second, participants in this study were presented intervals of 2, 3 or 4 s that had to be reproduced in setup similar to the seminal work of Elbert et al. (1991, Psychophysiology, 28(6), 648-55) while co-recording EEG and MEG. The EEG data showed a clear CNV during the standard and the reproduction interval. In the reproduction interval the CNV steadily builds up from the onset of interval for both stimulus and response locked data. The MEG data did not show a CNV-resembling ramping of activity, but only showed a pre-movement magnetic field (preMMF) that originated from the SMA, occurring approximately 0.6 s before the termination of the timed interval. These findings support the notion that signatures of timing are more straightforwardly measured using EEG, and show that the measured MEG signal from the SMA is constrained to the end of reproduction interval, before the voluntary movement. Moreover, we investigated a link between timing behavior and the early iCNV and late CNV amplitudes to evaluate the hypothesis that these amplitudes reflect the accumulation of temporal pulses. Larger iCNV amplitudes predicted shorter reproduced durations. This effect was more pronounced for the 2 s interval reproduction, suggesting that preparatory strategies depend on the length of reproduced interval. Similarly to Elbert et al. (1991, Psychophysiology, 28(6), 648-55), longer reproductions were associated with smaller CNV amplitudes, both between conditions and across participants within the same condition. As the temporal accumulation hypothesis predicts the inverse, these results support the proposal by Van Rijn et al. (2011, Frontiers in Integrative Neuroscience, 5) that the CNV reflects other temporally driven processes such as temporal expectation and preparation rather than temporal accumulation itself. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Carbon monoxide (CO) at low concentrations imparts protective effects in numerous preclinical small animal models of brain injury. Evidence of protection in large animal models of cerebral injury, however, has not been tested. Neurologic deficits following open heart surgery are likely related in part to ischemia reperfusion injury that occurs during cardiopulmonary bypass surgery. Using a model of deep hypothermic circulatory arrest (DHCA) in piglets, we evaluated the effects of CO to reduce cerebral injury. DHCA and cardiopulmonary bypass (CPB) induced significant alterations in metabolic demands, including a decrease in the oxygen/glucose index (OGI), an increase in lactate/glucose index (LGI) and a rise in cerebral blood pressure that ultimately resulted in increased cell death in the neocortex and hippocampus that was completely abrogated in piglets preconditioned with a low, safe dose of CO. Moreover CO-treated animals maintained normal, pre-CPB OGI and LGI and corresponding cerebral sinus pressures with no change in systemic hemodynamics or metabolic intermediates. Collectively, our data demonstrate that inhaled CO may be beneficial in preventing cerebral injury resulting from DHCA and offer important therapeutic options in newborns undergoing DHCA for open heart surgery.