3 recherche sur le mot-clé 'Alpha Rhythm'

Divergent aperiodic slope and alpha dynamics expose cortical excitability gradients in fragile X syndrome / Rana ELMAGHRABY in Molecular Autism, 16 (2025)  

Public ISBD [article]  inMolecular Autism > 16 (2025) . - 49 Titre : Divergent aperiodic slope and alpha dynamics expose cortical excitability gradients in fragile X syndrome Type de document : texte imprimé Auteurs : Rana ELMAGHRABY, Auteur ; Yanchen LIU, Auteur ; Priya RAMESH, Auteur ; Grace WESTERKAMP, Auteur ; Meredith A. NELSON, Auteur ; Travis LARSH, Auteur ; Elizabeth SMITH, Auteur ; Donald L. GILBERT, Auteur ; Steve W. WU, Auteur ; Craig ERICKSON, Auteur ; Ernest V. PEDAPATI, Auteur ; Rana ELMAGHRABY, Auteur ; Yanchen LIU, Auteur ; Priya RAMESH, Auteur ; Grace WESTERKAMP, Auteur ; Meredith A. NELSON, Auteur ; Travis LARSH, Auteur ; Elizabeth SMITH, Auteur ; Donald L. GILBERT, Auteur ; Steve W. WU, Auteur ; Craig ERICKSON, Auteur ; Ernest V. PEDAPATI, Auteur Article en page(s) : 49 Langues : Anglais (eng) Mots-clés : Humans  Fragile X Syndrome/physiopathology  Male  Female  Cortical Excitability/physiology  Young Adult  Adult  Electroencephalography  Adolescent  Alpha Rhythm  Case-Control Studies  Aperiodic slope  Cortical excitability  Eeg  Fragile X syndrome  Sex differences  Source localization  SpecParam Index. décimale : PER Périodiques Résumé : BACKGROUND: Fragile X syndrome (FXS) is characterized by cortical hyperexcitability, a core neurophysiological feature that contributes to sensory hypersensitivity, cognitive dysfunction, and other disabling symptoms. This disruption in excitatory-inhibitory balance is a key pharmacological target, yet reliable biomarkers to quantify it noninvasively remain limited. Spectral slope, derived from the aperiodic component of the EEG power spectrum, has emerged as a potential index of cortical excitability. Here, we evaluated spectral slope and theta-alpha peak frequency in individuals with FXS to assess their utility as candidate neurophysiological biomarkers. METHODS: Five minutes of resting state EEG data were collected from 70 subjects with FXS (mean age 20.5 ± 10 years; 32 females) and 71 age-matched controls (mean age 22.2 ± 10.7 years; 30 females). The Spectral Parameterization toolbox (SpecParam) was used to separate periodic and aperiodic components of the source localized power spectra and characterize aperiodic slope and theta-alpha peak frequency. RESULTS: Statistical modeling of aperiodic slope revealed a significant two-way interaction between sex and diagnostic group, but no interaction with brain lobe. Among males, the aperiodic slope was significantly decreased in FXS, indicating greater cortical excitability, compared to typically developing controls (TDC), whereas no difference was observed between FXS and TDC females. For peak alpha frequency, statistical modeling identified significant two-way interactions between sex and diagnostic group, and between brain lobe and diagnostic group, but no significant three-way interaction. LIMITATIONS: This study is limited by the absence of non-invasive measures of cortical fragile X mental retardation protein (FMRP). Additionally, participants were not stratified by mosaic status and FMRP levels were not quantified, which could affect variability and interpretation. CONCLUSION: Compared to traditional band-limited power measures, aperiodic slope provides a more direct and validated index of excitation-inhibition balance. Our findings of reduced aperiodic slope in male subjects with FXS align with preclinical circuit-level evidence of increased excitability in FXS and are consistent with previous findings of reduced individual alpha peak frequency, supporting with thalamocortical dysrhythmia models of FXS. Importantly, aperiodic slope measurements can be applied directly to various modalities of local field potential data, enabling more robust cross-species and translational comparisons. En ligne : https://dx.doi.org/10.1186/s13229-025-00682-0 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=569 [article] Divergent aperiodic slope and alpha dynamics expose cortical excitability gradients in fragile X syndrome [texte imprimé] / Rana ELMAGHRABY, Auteur ; Yanchen LIU, Auteur ; Priya RAMESH, Auteur ; Grace WESTERKAMP, Auteur ; Meredith A. NELSON, Auteur ; Travis LARSH, Auteur ; Elizabeth SMITH, Auteur ; Donald L. GILBERT, Auteur ; Steve W. WU, Auteur ; Craig ERICKSON, Auteur ; Ernest V. PEDAPATI, Auteur ; Rana ELMAGHRABY, Auteur ; Yanchen LIU, Auteur ; Priya RAMESH, Auteur ; Grace WESTERKAMP, Auteur ; Meredith A. NELSON, Auteur ; Travis LARSH, Auteur ; Elizabeth SMITH, Auteur ; Donald L. GILBERT, Auteur ; Steve W. WU, Auteur ; Craig ERICKSON, Auteur ; Ernest V. PEDAPATI, Auteur . - 49. Langues : Anglais (eng) in Molecular Autism > 16 (2025) . - 49 Mots-clés : Humans  Fragile X Syndrome/physiopathology  Male  Female  Cortical Excitability/physiology  Young Adult  Adult  Electroencephalography  Adolescent  Alpha Rhythm  Case-Control Studies  Aperiodic slope  Cortical excitability  Eeg  Fragile X syndrome  Sex differences  Source localization  SpecParam Index. décimale : PER Périodiques Résumé : BACKGROUND: Fragile X syndrome (FXS) is characterized by cortical hyperexcitability, a core neurophysiological feature that contributes to sensory hypersensitivity, cognitive dysfunction, and other disabling symptoms. This disruption in excitatory-inhibitory balance is a key pharmacological target, yet reliable biomarkers to quantify it noninvasively remain limited. Spectral slope, derived from the aperiodic component of the EEG power spectrum, has emerged as a potential index of cortical excitability. Here, we evaluated spectral slope and theta-alpha peak frequency in individuals with FXS to assess their utility as candidate neurophysiological biomarkers. METHODS: Five minutes of resting state EEG data were collected from 70 subjects with FXS (mean age 20.5 ± 10 years; 32 females) and 71 age-matched controls (mean age 22.2 ± 10.7 years; 30 females). The Spectral Parameterization toolbox (SpecParam) was used to separate periodic and aperiodic components of the source localized power spectra and characterize aperiodic slope and theta-alpha peak frequency. RESULTS: Statistical modeling of aperiodic slope revealed a significant two-way interaction between sex and diagnostic group, but no interaction with brain lobe. Among males, the aperiodic slope was significantly decreased in FXS, indicating greater cortical excitability, compared to typically developing controls (TDC), whereas no difference was observed between FXS and TDC females. For peak alpha frequency, statistical modeling identified significant two-way interactions between sex and diagnostic group, and between brain lobe and diagnostic group, but no significant three-way interaction. LIMITATIONS: This study is limited by the absence of non-invasive measures of cortical fragile X mental retardation protein (FMRP). Additionally, participants were not stratified by mosaic status and FMRP levels were not quantified, which could affect variability and interpretation. CONCLUSION: Compared to traditional band-limited power measures, aperiodic slope provides a more direct and validated index of excitation-inhibition balance. Our findings of reduced aperiodic slope in male subjects with FXS align with preclinical circuit-level evidence of increased excitability in FXS and are consistent with previous findings of reduced individual alpha peak frequency, supporting with thalamocortical dysrhythmia models of FXS. Importantly, aperiodic slope measurements can be applied directly to various modalities of local field potential data, enabling more robust cross-species and translational comparisons. En ligne : https://dx.doi.org/10.1186/s13229-025-00682-0 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=569

White matter microstructure as a potential contributor to differences in resting state alpha activity between neurotypical and autistic children: a longitudinal multimodal imaging study / Heather L. GREEN ; Marybeth MCNAMEE ; Rose E. FRANZEN ; Marissa A. DIPIERO ; Jeffrey I. BERMAN ; Matthew KU ; Luke BLOY ; Song LIU ; Megan AIREY ; Sophia GOLDIN ; Lisa BLASKEY ; Emily S. KUSCHNER ; Mina KIM ; Kimberly KONKA ; Gregory A. MILLER ; J. Christopher EDGAR in Molecular Autism, 16 (2025)  

Public ISBD [article]  inMolecular Autism > 16 (2025) . - 19 Titre : White matter microstructure as a potential contributor to differences in resting state alpha activity between neurotypical and autistic children: a longitudinal multimodal imaging study Type de document : texte imprimé Auteurs : Heather L. GREEN, Auteur ; Marybeth MCNAMEE, Auteur ; Rose E. FRANZEN, Auteur ; Marissa A. DIPIERO, Auteur ; Jeffrey I. BERMAN, Auteur ; Matthew KU, Auteur ; Luke BLOY, Auteur ; Song LIU, Auteur ; Megan AIREY, Auteur ; Sophia GOLDIN, Auteur ; Lisa BLASKEY, Auteur ; Emily S. KUSCHNER, Auteur ; Mina KIM, Auteur ; Kimberly KONKA, Auteur ; Gregory A. MILLER, Auteur ; J. Christopher EDGAR, Auteur Article en page(s) : 19 Langues : Anglais (eng) Mots-clés : Humans  White Matter/diagnostic imaging/pathology  Child  Male  Female  Longitudinal Studies  Magnetoencephalography  Diffusion Tensor Imaging  Multimodal Imaging  Autism Spectrum Disorder/diagnostic imaging/physiopathology  Rest  Alpha Rhythm  Autistic Disorder/diagnostic imaging/physiopathology  Brain/diagnostic imaging/physiopathology/pathology  Autism spectrum disorder  Dti  Maturation  Peak alpha frequency  Human ethics: This study was approved by the Institutional Review Board of  Children?s Hospital of Philadelphia (IRB 15-012531) and performed in accordance  with the Declaration of Helsinki. Parents gave written informed consent and the  children gave verbal and written assent. Index. décimale : PER Périodiques Résumé : We and others have demonstrated the resting-state (RS) peak alpha frequency (PAF) as a potential clinical marker for young children with autism spectrum disorder (ASD), with previous studies observing a higher PAF in school-age children with ASD versus typically developing (TD) children, as well as an association between the RS PAF and measures of processing speed in TD but not ASD. The brain mechanisms associated with these findings are unknown. A few studies have found that in children more mature optic radiation white matter is associated with a higher PAF. Other studies have reported white matter and neural activity associations in TD but not ASD. The present study hypothesized that group differences in the RS PAF are due, in part, to group differences in optic radiation white matter and PAF associations. The maturation of the RS PAF (measured using magnetoencephalography(MEG)), optic radiation white matter (measured using diffusion tensor imaging(DTI)), and associations with processing speed were assessed in a longitudinal cohort of TD and ASD children. Time 1 MEG and DTI measures were obtained at 6-8 years old (59TD and 56ASD) with follow-up brain measures collected?~ 1.5 and ~ 3 years later. The parietal-occipital PAF increased with age in both groups by 0.13 Hz/year, with a main effect of group showing the expected higher PAF in ASD than TD (an average of 0.26 Hz across the 3 time points). Across age, the RS PAF predicted processing speed in TD but not ASD. Finally, more mature optic radiation white matter measures (FA, RD, MD, AD) were associated with a higher PAF in both groups. Present findings provide additional evidence supporting the use of the RS PAF as a brain marker in children with ASD 6-10 years old, and replicate findings of an association between the RS PAF and processing speed in TD but not ASD. The hypothesis that the RS PAF group differences (with ASD leading TD by about 2 years) would be explained by group differences in optic radiation white matter was not supported, with brain structure-function associations indicating that more mature optic radiation white matter is associated with a higher RS PAF in both groups. En ligne : https://dx.doi.org/10.1186/s13229-025-00646-4 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=555 [article] White matter microstructure as a potential contributor to differences in resting state alpha activity between neurotypical and autistic children: a longitudinal multimodal imaging study [texte imprimé] / Heather L. GREEN, Auteur ; Marybeth MCNAMEE, Auteur ; Rose E. FRANZEN, Auteur ; Marissa A. DIPIERO, Auteur ; Jeffrey I. BERMAN, Auteur ; Matthew KU, Auteur ; Luke BLOY, Auteur ; Song LIU, Auteur ; Megan AIREY, Auteur ; Sophia GOLDIN, Auteur ; Lisa BLASKEY, Auteur ; Emily S. KUSCHNER, Auteur ; Mina KIM, Auteur ; Kimberly KONKA, Auteur ; Gregory A. MILLER, Auteur ; J. Christopher EDGAR, Auteur . - 19. Langues : Anglais (eng) in Molecular Autism > 16 (2025) . - 19 Mots-clés : Humans  White Matter/diagnostic imaging/pathology  Child  Male  Female  Longitudinal Studies  Magnetoencephalography  Diffusion Tensor Imaging  Multimodal Imaging  Autism Spectrum Disorder/diagnostic imaging/physiopathology  Rest  Alpha Rhythm  Autistic Disorder/diagnostic imaging/physiopathology  Brain/diagnostic imaging/physiopathology/pathology  Autism spectrum disorder  Dti  Maturation  Peak alpha frequency  Human ethics: This study was approved by the Institutional Review Board of  Children?s Hospital of Philadelphia (IRB 15-012531) and performed in accordance  with the Declaration of Helsinki. Parents gave written informed consent and the  children gave verbal and written assent. Index. décimale : PER Périodiques Résumé : We and others have demonstrated the resting-state (RS) peak alpha frequency (PAF) as a potential clinical marker for young children with autism spectrum disorder (ASD), with previous studies observing a higher PAF in school-age children with ASD versus typically developing (TD) children, as well as an association between the RS PAF and measures of processing speed in TD but not ASD. The brain mechanisms associated with these findings are unknown. A few studies have found that in children more mature optic radiation white matter is associated with a higher PAF. Other studies have reported white matter and neural activity associations in TD but not ASD. The present study hypothesized that group differences in the RS PAF are due, in part, to group differences in optic radiation white matter and PAF associations. The maturation of the RS PAF (measured using magnetoencephalography(MEG)), optic radiation white matter (measured using diffusion tensor imaging(DTI)), and associations with processing speed were assessed in a longitudinal cohort of TD and ASD children. Time 1 MEG and DTI measures were obtained at 6-8 years old (59TD and 56ASD) with follow-up brain measures collected?~ 1.5 and ~ 3 years later. The parietal-occipital PAF increased with age in both groups by 0.13 Hz/year, with a main effect of group showing the expected higher PAF in ASD than TD (an average of 0.26 Hz across the 3 time points). Across age, the RS PAF predicted processing speed in TD but not ASD. Finally, more mature optic radiation white matter measures (FA, RD, MD, AD) were associated with a higher PAF in both groups. Present findings provide additional evidence supporting the use of the RS PAF as a brain marker in children with ASD 6-10 years old, and replicate findings of an association between the RS PAF and processing speed in TD but not ASD. The hypothesis that the RS PAF group differences (with ASD leading TD by about 2 years) would be explained by group differences in optic radiation white matter was not supported, with brain structure-function associations indicating that more mature optic radiation white matter is associated with a higher RS PAF in both groups. En ligne : https://dx.doi.org/10.1186/s13229-025-00646-4 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=555

Atypical neural variability in carriers of 16p11.2 copy number variants / Reem AL-JAWAHIRI in Autism Research, 12-9 (September 2019)  

Public ISBD [article]  inAutism Research > 12-9 (September 2019) . - p.1322-1333 Titre : Atypical neural variability in carriers of 16p11.2 copy number variants Type de document : texte imprimé Auteurs : Reem AL-JAWAHIRI, Auteur ; Myles JONES, Auteur ; Elizabeth MILNE, Auteur Article en page(s) : p.1322-1333 Langues : Anglais (eng) Mots-clés : alpha rhythm  cognitive neuroscience  copy number variation/copy number variants  electroencephalography  event-related potentials  gene-dosage effect  genetic/genomic syndromes Index. décimale : PER Périodiques Résumé : Copy number variations (CNVs) at the 16p11.2 chromosomal region are associated with myriad clinical features including intellectual disability and autism spectrum disorder. The aim of this study is to determine whether 16p11.2 deletion (DEL) and duplication (DUP) carriers demonstrate a distinct and reciprocal pattern of electroencephalography (EEG) activity as represented by neural variability measures. EEG data were previously collected as part of the Simons Variation in Individuals Project. Variability measures, as estimated by single-trial ERP and spectral power analyses in the alpha and beta frequency bands, in addition to signal-to-noise ratios (SNRs), were analyzed in DEL (n = 20), DUP (n = 8), and typical (n = 11) groups. We also analyzed mean visual evoked potentials and spectral power (alpha and beta power) to facilitate comparisons with other studies of associated disorders and CNVs. From measures of single-trial variability, we found higher intraparticipant variability in P1 amplitude and timecourse amplitude in DEL compared to controls. Compared to DUP, DEL showed higher variability in absolute alpha and absolute beta power but lower variability in P1 latency. SNRs did not differ between the groups. From measures of amplitude, latency, and spectral power, DUP showed lower relative alpha power compared to controls. Although it is yet unclear whether 16p11.2 CNV dosage impacts neural activity in an opposing manner, findings suggest that 16p11.2 DEL impacts the level of variability of neural responses. Higher neural variability may play a role in a range of cognitive processes in 16p11.2 CNV carriers. Autism Res 2019, 12: 1322-1333. (c) 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The study analyzed the consistency of patterns of brain waves and rhythms in those affected with a loss or gain of DNA material in the 16p11.2 region. Compared with typical individuals, 16p11.2 deletion carriers showed greater inconsistency in the way the brain responds to the same visual event. This high inconsistency in brain activity may play a role in some core symptoms in 16p11.2 copy number variation carriers. En ligne : http://dx.doi.org/10.1002/aur.2166 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=406 [article] Atypical neural variability in carriers of 16p11.2 copy number variants [texte imprimé] / Reem AL-JAWAHIRI, Auteur ; Myles JONES, Auteur ; Elizabeth MILNE, Auteur . - p.1322-1333. Langues : Anglais (eng) in Autism Research > 12-9 (September 2019) . - p.1322-1333 Mots-clés : alpha rhythm  cognitive neuroscience  copy number variation/copy number variants  electroencephalography  event-related potentials  gene-dosage effect  genetic/genomic syndromes Index. décimale : PER Périodiques Résumé : Copy number variations (CNVs) at the 16p11.2 chromosomal region are associated with myriad clinical features including intellectual disability and autism spectrum disorder. The aim of this study is to determine whether 16p11.2 deletion (DEL) and duplication (DUP) carriers demonstrate a distinct and reciprocal pattern of electroencephalography (EEG) activity as represented by neural variability measures. EEG data were previously collected as part of the Simons Variation in Individuals Project. Variability measures, as estimated by single-trial ERP and spectral power analyses in the alpha and beta frequency bands, in addition to signal-to-noise ratios (SNRs), were analyzed in DEL (n = 20), DUP (n = 8), and typical (n = 11) groups. We also analyzed mean visual evoked potentials and spectral power (alpha and beta power) to facilitate comparisons with other studies of associated disorders and CNVs. From measures of single-trial variability, we found higher intraparticipant variability in P1 amplitude and timecourse amplitude in DEL compared to controls. Compared to DUP, DEL showed higher variability in absolute alpha and absolute beta power but lower variability in P1 latency. SNRs did not differ between the groups. From measures of amplitude, latency, and spectral power, DUP showed lower relative alpha power compared to controls. Although it is yet unclear whether 16p11.2 CNV dosage impacts neural activity in an opposing manner, findings suggest that 16p11.2 DEL impacts the level of variability of neural responses. Higher neural variability may play a role in a range of cognitive processes in 16p11.2 CNV carriers. Autism Res 2019, 12: 1322-1333. (c) 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The study analyzed the consistency of patterns of brain waves and rhythms in those affected with a loss or gain of DNA material in the 16p11.2 region. Compared with typical individuals, 16p11.2 deletion carriers showed greater inconsistency in the way the brain responds to the same visual event. This high inconsistency in brain activity may play a role in some core symptoms in 16p11.2 copy number variation carriers. En ligne : http://dx.doi.org/10.1002/aur.2166 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=406