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Rubem Carlos Araújo Guedes - One of the best experts on this subject based on the ideXlab platform.
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Hypercaloric high-lipid diet and Brain development: Effects on cortical spreading depression in adult rats
Nutritional neuroscience, 2013Co-Authors: Paula Catirina Pereira Da Silva Germano, Débora De Lima E Silva, Geórgia De Sousa Ferreira Soares, Ângela Amâncio Dos Santos, Rubem Carlos Araújo GuedesAbstract:Nutritional conditions early in life constitute one of the environmental factors that can influence Brain Electrophysiology, as evaluated through the phenomenon denominated as cortical spreading depression (CSD). Objective To evaluate the effects of hypercaloric diet intake in different phases of life on CSD features in adult rats. Methods Newborn Wistar rats were suckled by dams fed a high-lipid (cafeteria) hypercaloric diet during the lactation period. After suckling, part of the pups remained in the high-lipid diet until the end of the experiment in adulthood (group ‘full-life’ FL), and the other part received the control (lab chow) diet (group L). A third group received the hypercaloric diet only at adulthood (group Ad). When the animals reached 90–93 days of life, CSD was recorded. Results CSD propagation velocities (in mm/minute) and CSD amplitudes (in mV) were reduced (P
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Aging-dependent Brain electrophysiological effects in rats after distinct lactation conditions, and treadmill exercise: a spreading depression analysis.
Experimental gerontology, 2012Co-Authors: Manuella Batista-de-oliveira, Rosângela Figueiredo Mendes-da-silva, Andréia Lopes, Rubem Carlos Araújo GuedesAbstract:Abstract Aging-related neurophysiological alterations are a matter of growing concern in gerontology. Physical exercise has been therapeutically employed to ameliorate aging-associated deleterious neurological changes. The aging process, as well as the effects of treadmill exercise on Brain excitability, can be influenced by nutritional demands during lactation. In this study we investigated whether physical exercise, lactation conditions, and aging interact and modulate Brain Electrophysiology as indexed by the excitability-related phenomenon known as cortical spreading depression (CSD). Wistar male rats were suckled in litters of 12 or 6 pups (constituting two groups named L12 and L6), with different lactation conditions. Each group was subdivided into exercised (treadmill) and sedentary. CSD was recorded immediately after the exercise period for young, adult, and aged groups (respectively 45–60, 120–130, and 600–700 days old). In L6 groups, the mean CSD velocity (in mm/min) ranged from 2.57 ± 0.24 in aged rats to 3.67 ± 0.13 in young rats, indicating an aging-related CSD deceleration. The L12 condition accelerated CSD (velocities ranging from 3.11 ± 0.21 to 4.35 ± 0.16 in aged and young rats, respectively) while treadmill exercise decelerated it in both L6 groups (range: 3.02 ± 0.19 to 2.57 ± 0.24) and L12 groups (3.32 ± 0.16 to 3.11 ± 0.21), with an observed interaction between factors in the aged group. Furthermore, aging led to a significant failure of CSD propagation. These results contribute to the understanding of underlying mechanisms by which exercise and aging influence Brain electrophysiological functioning, previously associated with distinct lactation conditions during the period of Brain development.
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Early malnutrition, but not age, modulates in the rat the l-Arginine facilitating effect on cortical spreading depression
Neuroscience letters, 2008Co-Authors: Marília Ferreira Frazão, Luciana Maria Silva De Seixas Maia, Rubem Carlos Araújo GuedesAbstract:Nutritional factors acting during Brain development can permanently alter Brain Electrophysiology. L-Arginine is the precursor of nitric oxide synthesis, which can modulate Brain function. Here we investigated the effect of early-in-life administration (during postnatal days 7-28) of L-Arginine (300 mg/(kg day)) on cortical spreading depression (CSD), recorded in well-nourished and malnourished (large litters technique) rats aged 30-40 days (young) and 90-110 days (adult). Compared to water-treated controls, well-nourished L-Arginine-treated rats, but not the malnourished ones, displayed higher CSD velocities (P
Anup Patel - One of the best experts on this subject based on the ideXlab platform.
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Brain Electrophysiology reveals intact processing of speech sounds in deformational plagiocephaly
Plastic and Reconstructive Surgery, 2014Co-Authors: Peter W Hashim, Roberto Travieso, Marika C Coffman, Cora E Mukerji, Adam J Naples, Rachael M Tillman, Jordan Terner, Nicole Landi, John A. Persing, Anup PatelAbstract:BACKGROUND: The prevalence of deformational plagiocephaly has risen dramatically in recent years, now affecting 15 percent or more of infants. Prior research using developmental scales suggests that these children may be at elevated risk for developmental delays. However, the low positive predictive value of such instruments in identifying long-term impairment, coupled with their poor reliability in infants, warrants the development of methods to more precisely measure Brain function in craniofacial patients. Event-related potentials offer a direct measure of cortical activity that is highly applicable to young populations and has been implemented in other disorders to predict long-term cognitive functioning. The current study used event-related potentials to contrast neural correlates of auditory perception in infants with deformational plagiocephaly and typically developing children. METHODS: Event-related potentials were recorded while 16 infants with deformational plagiocephaly and 18 nonaffected controls passively listened to speech sounds. Given prior research suggesting their association with subsequent functioning, analyses focused on the P150 and N450 event-related potential components. RESULTS: Deformational plagiocephaly patients and normal controls showed comparable cortical responses to speech sounds at both auditory event-related potential components. CONCLUSIONS: Children with deformational plagiocephaly demonstrate neural responses to language that are consistent with normative expectations and comparable to those of typical children. These results indicate that head shape deformity secondary to supine sleep is not associated with impairments in auditory processing. The applicability of the current methods in early infancy suggests that electrophysiologic Brain recordings represent a promising method of monitoring Brain development in children with cranial disorders. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.
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Brain Electrophysiology reveals intact processing of speech sounds in deformational plagiocephaly.
Plastic and reconstructive surgery, 2014Co-Authors: Peter W Hashim, Roberto Travieso, Marika C Coffman, Cora E Mukerji, Adam J Naples, Rachael M Tillman, Jordan Terner, Nicole Landi, John A. Persing, Anup PatelAbstract:Background:The prevalence of deformational plagiocephaly has risen dramatically in recent years, now affecting 15 percent or more of infants. Prior research using developmental scales suggests that these children may be at elevated risk for developmental delays. However, the low positive predictive
Eleanor A. Maguire - One of the best experts on this subject based on the ideXlab platform.
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Towards OPM-MEG in a virtual reality environment
NeuroImage, 2019Co-Authors: Gillian Roberts, Niall Holmes, Nicholas Alexander, Elena Boto, James Leggett, Ryan M. Hill, Vishal Shah, Molly Rea, Richard Vaughan, Eleanor A. MaguireAbstract:Virtual reality (VR) provides an immersive environment in which a participant can experience a feeling of presence in a virtual world. Such environments generate strong emotional and physical responses and have been used for wide-ranging applications. The ability to collect functional neuroimaging data whilst a participant is immersed in VR would represent a step change for experimental paradigms; unfortunately, traditional Brain imaging requires participants to remain still, limiting the scope of naturalistic interaction within VR. Recently however, a new type of magnetoencephalography (MEG) device has been developed, that employs scalp-mounted optically-pumped magnetometers (OPMs) to measure Brain Electrophysiology. Lightweight OPMs, coupled with precise control of the background magnetic field, enables participant movement during data acquisition. Here, we exploit this technology to acquire MEG data whilst a participant uses a virtual reality head-mounted display (VRHMD). We show that, despite increased magnetic interference from the VRHMD, we were able to measure modulation of alpha-band oscillations, and the visual evoked field. Moreover, in a VR experiment in which a participant had to move their head to look around a virtual wall and view a visual stimulus, we showed that the measured MEG signals map spatially in accordance with the known organisation of primary visual cortex. This technique could transform the type of neuroscientific experiment that can be undertaken using functional neuroimaging.
Sylvain Baillet - One of the best experts on this subject based on the ideXlab platform.
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Magnetoencephalography for Brain Electrophysiology and imaging
Nature Neuroscience, 2017Co-Authors: Sylvain BailletAbstract:We review the aspects that uniquely characterize magnetoencephalography (MEG) among the techniques available to explore and resolve Brain function and dysfunction. While emphasizing its specific strengths in terms of millisecond source imaging, we also identify and discuss current practical challenges, in particular in signal extraction and interpretation. We also take issue with some perceived disadvantages of MEG, including the misconception that the technique is redundant with electroencephalography. Overall, MEG contributes uniquely to our deeper comprehension of both regional and large-scale Brain dynamics: from the functions of neural oscillations and the nature of event-related Brain activation, to the mechanisms of functional connectivity between regions and the emergence of modes of network communication in Brain systems. We expect MEG to play an increasing and pivotal role in the elucidation of these grand mechanistic principles of cognitive, systems and clinical neuroscience. Magnetoencephalography (MEG) tracks the millisecond electrical activity of the Brain noninvasively. This review emphasizes MEG's unique assets, especially in terms of imaging and resolving the mechanisms underlying the apparent complexity of polyrhythmic Brain dynamics. It also identifies practical challenges and clarifies misconceptions about the technique.
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magnetoencephalography for Brain Electrophysiology and imaging
Nature Neuroscience, 2017Co-Authors: Sylvain BailletAbstract:We review the aspects that uniquely characterize magnetoencephalography (MEG) among the techniques available to explore and resolve Brain function and dysfunction. While emphasizing its specific strengths in terms of millisecond source imaging, we also identify and discuss current practical challenges, in particular in signal extraction and interpretation. We also take issue with some perceived disadvantages of MEG, including the misconception that the technique is redundant with electroencephalography. Overall, MEG contributes uniquely to our deeper comprehension of both regional and large-scale Brain dynamics: from the functions of neural oscillations and the nature of event-related Brain activation, to the mechanisms of functional connectivity between regions and the emergence of modes of network communication in Brain systems. We expect MEG to play an increasing and pivotal role in the elucidation of these grand mechanistic principles of cognitive, systems and clinical neuroscience.
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Time-resolved phase-amplitude coupling in neural oscillations
NeuroImage, 2017Co-Authors: Soheila Samiee, Sylvain BailletAbstract:Abstract Cross-frequency coupling between neural oscillations is a phenomenon observed across spatial scales in a wide range of preparations, including human non-invasive Electrophysiology. Although the functional role and mechanisms involved are not entirely understood, the concept of interdependent neural oscillations drives an active field of research to comprehend the ubiquitous polyrhythmic activity of the Brain, beyond empirical observations. Phase-amplitude coupling, a particular form of cross-frequency coupling between bursts of high-frequency oscillations and the phase of lower frequency rhythms, has recently received considerable attention. However, the measurement methods have relatively poor sensitivity and require long segments of experimental data. This obliterates the resolution of fast changes in coupling related to behavior, and more generally, to the non-stationary dynamics of Brain Electrophysiology. We propose a new measure of phase-amplitude coupling that can resolve up to one, optimally two, cycles of the underlying slow frequency component. The method also provides a measure of the coupling strength, for augmented insight into the mechanisms involved. We demonstrate the technique with synthesized data and compare its performances with existing methods. We also show that the method reveals rapid changes in coupling parameters in data from the entorhinal cortex of a free-behaving rat. The time-resolved changes revealed are compatible with behavior and complement observed modulations of oscillatory power. We anticipate that this new measure of dynamic phase-amplitude coupling will contribute to accelerate research into the dynamics of inter-dependent oscillatory components related to Brain functions and dysfunctions.
Peter W Hashim - One of the best experts on this subject based on the ideXlab platform.
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Brain Electrophysiology reveals intact processing of speech sounds in deformational plagiocephaly
Plastic and Reconstructive Surgery, 2014Co-Authors: Peter W Hashim, Roberto Travieso, Marika C Coffman, Cora E Mukerji, Adam J Naples, Rachael M Tillman, Jordan Terner, Nicole Landi, John A. Persing, Anup PatelAbstract:BACKGROUND: The prevalence of deformational plagiocephaly has risen dramatically in recent years, now affecting 15 percent or more of infants. Prior research using developmental scales suggests that these children may be at elevated risk for developmental delays. However, the low positive predictive value of such instruments in identifying long-term impairment, coupled with their poor reliability in infants, warrants the development of methods to more precisely measure Brain function in craniofacial patients. Event-related potentials offer a direct measure of cortical activity that is highly applicable to young populations and has been implemented in other disorders to predict long-term cognitive functioning. The current study used event-related potentials to contrast neural correlates of auditory perception in infants with deformational plagiocephaly and typically developing children. METHODS: Event-related potentials were recorded while 16 infants with deformational plagiocephaly and 18 nonaffected controls passively listened to speech sounds. Given prior research suggesting their association with subsequent functioning, analyses focused on the P150 and N450 event-related potential components. RESULTS: Deformational plagiocephaly patients and normal controls showed comparable cortical responses to speech sounds at both auditory event-related potential components. CONCLUSIONS: Children with deformational plagiocephaly demonstrate neural responses to language that are consistent with normative expectations and comparable to those of typical children. These results indicate that head shape deformity secondary to supine sleep is not associated with impairments in auditory processing. The applicability of the current methods in early infancy suggests that electrophysiologic Brain recordings represent a promising method of monitoring Brain development in children with cranial disorders. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.
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Brain Electrophysiology reveals intact processing of speech sounds in deformational plagiocephaly.
Plastic and reconstructive surgery, 2014Co-Authors: Peter W Hashim, Roberto Travieso, Marika C Coffman, Cora E Mukerji, Adam J Naples, Rachael M Tillman, Jordan Terner, Nicole Landi, John A. Persing, Anup PatelAbstract:Background:The prevalence of deformational plagiocephaly has risen dramatically in recent years, now affecting 15 percent or more of infants. Prior research using developmental scales suggests that these children may be at elevated risk for developmental delays. However, the low positive predictive