2023
Auditory evoked response to an oddball paradigm in children wearing cochlear implants
Deroche M, Wolfe J, Neumann S, Manning J, Towler W, Alemi R, Bien A, Koirala N, Hanna L, Henry L, Gracco V. Auditory evoked response to an oddball paradigm in children wearing cochlear implants. Clinical Neurophysiology 2023, 149: 133-145. PMID: 36965466, DOI: 10.1016/j.clinph.2023.02.179.Peer-Reviewed Original ResearchConceptsMismatch negativityCochlear implantsLow languageOddball paradigmPositive componentHigh languageNormal hearingReliable mismatch negativityLate positive componentN1-P2 complexAge-appropriate skillsHigh-density electroencephalographySecond positive componentP3 responseAuditory processingNH childrenP3 componentLanguage delayDifference waveformsDifferentiated childrenImplanted childrenEarly P3Better literacy skillsDevelopmental outcomesLiteracy skills
2022
Sensorimotor Cortical Activity during Respiratory Arousals in Obstructive Sleep Apnea
Bahr-Hamm K, Koirala N, Hanif M, Gouveris H, Muthuraman M. Sensorimotor Cortical Activity during Respiratory Arousals in Obstructive Sleep Apnea. International Journal Of Molecular Sciences 2022, 24: 47. PMID: 36613490, PMCID: PMC9820672, DOI: 10.3390/ijms24010047.Peer-Reviewed Original ResearchConceptsModerate OSA patientsSevere OSASensorimotor cortical activityOSA patientsRespiratory arousalsCortical activityObstructive sleep apnea patientsSevere OSA patientsObstructive sleep apneaSignificant decreaseSleep apnea patientsSleep stagesRaw electroencephalography dataModerate OSASleep apneaRespiratory eventsApnea patientsDifferential diagnosisSleep stage N1PatientsAutonomic activationStage N1Cortical arousalPathophysiologic traitsOSAMachine learning aided classification of tremor in multiple sclerosis
Hossen A, Anwar A, Koirala N, Ding H, Budker D, Wickenbrock A, Heute U, Deuschl G, Groppa S, Muthuraman M. Machine learning aided classification of tremor in multiple sclerosis. EBioMedicine 2022, 82: 104152. PMID: 35834887, PMCID: PMC9287478, DOI: 10.1016/j.ebiom.2022.104152.Peer-Reviewed Original Research
2021
Widespread effects of dMRI data quality on diffusion measures in children
Koirala N, Kleinman D, Perdue MV, Su X, Villa M, Grigorenko EL, Landi N. Widespread effects of dMRI data quality on diffusion measures in children. Human Brain Mapping 2021, 43: 1326-1341. PMID: 34799957, PMCID: PMC8837592, DOI: 10.1002/hbm.25724.Peer-Reviewed Original ResearchFrequency-specific network activity predicts bradykinesia severity in Parkinson’s disease
Muthuraman M, Palotai M, Jávor-Duray B, Kelemen A, Koirala N, Halász L, Erőss L, Fekete G, Bognár L, Deuschl G, Tamás G. Frequency-specific network activity predicts bradykinesia severity in Parkinson’s disease. NeuroImage Clinical 2021, 32: 102857. PMID: 34662779, PMCID: PMC8526781, DOI: 10.1016/j.nicl.2021.102857.Peer-Reviewed Original ResearchConceptsSlope of changeContralateral stimulationPremotor cortexParkinson's diseasePrimary motorPresent cross-sectional studyBasal ganglia-thalamoBilateral subthalamic stimulationCross-sectional studyHigh beta frequency bandBeta frequency bandsParkinsonian patientsSubthalamic stimulationContralateral sideScreening periodSubthalamic nucleusBradykinesia severityCortical circuitsGamma frequency bandBradykinesiaDiseaseHigh-gamma frequency bandStimulation levelsStimulationCortexNeurite density and arborization is associated with reading skill and phonological processing in children
Koirala N, Perdue MV, Su X, Grigorenko EL, Landi N. Neurite density and arborization is associated with reading skill and phonological processing in children. NeuroImage 2021, 241: 118426. PMID: 34303796, PMCID: PMC8539928, DOI: 10.1016/j.neuroimage.2021.118426.Peer-Reviewed Original ResearchStructural brain network characteristics in patients with episodic and chronic migraine
Michels L, Koirala N, Groppa S, Luechinger R, Gantenbein A, Sandor P, Kollias S, Riederer F, Muthuraman M. Structural brain network characteristics in patients with episodic and chronic migraine. The Journal Of Headache And Pain 2021, 22: 8. PMID: 33657996, PMCID: PMC7927231, DOI: 10.1186/s10194-021-01216-8.Peer-Reviewed Original Research
2020
Mapping of subthalamic nucleus using microelectrode recordings during deep brain stimulation
Koirala N, Serrano L, Paschen S, Falk D, Anwar A, Kuravi P, Deuschl G, Groppa S, Muthuraman M. Mapping of subthalamic nucleus using microelectrode recordings during deep brain stimulation. Scientific Reports 2020, 10: 19241. PMID: 33159098, PMCID: PMC7648837, DOI: 10.1038/s41598-020-74196-5.Peer-Reviewed Original ResearchConceptsMicroelectrode recordingsBackground activityStereotactic magnetic resonance imagingLow beta frequency rangeDeep brain stimulation surgeryBilateral STN-DBSSide effect ratioDeep brain stimulationBeta frequency rangeMagnetic resonance imagingSTN-DBSAwake patientsLead placementSubthalamic nucleusIntraoperative decisionAnatomical sitesBrain stimulationDBS electrodesOptimal target localizationResonance imagingMaximum spike rateBeta rangeSpike ratePatientsImplantationCross-frequency coupling between gamma oscillations and deep brain stimulation frequency in Parkinson’s disease
Muthuraman M, Bange M, Koirala N, Ciolac D, Pintea B, Glaser M, Tinkhauser G, Brown P, Deuschl G, Groppa S. Cross-frequency coupling between gamma oscillations and deep brain stimulation frequency in Parkinson’s disease. Brain 2020, 143: 3393-3407. PMID: 33150359, PMCID: PMC7116448, DOI: 10.1093/brain/awaa297.Peer-Reviewed Original ResearchConceptsDeep brain stimulationBrain stimulationParkinson's diseaseStimulation frequencyCross-frequency couplingMotor symptomsSubthalamic nucleusGamma oscillationsDeep Brain Stimulation FrequencyOscillatory activityPhysiological neural activityMotor function recoveryEffective deep brain stimulationHigh-frequency stimulationPathological oscillatory activityCross-frequency interactionsCortico-subcortical networksDifferent oscillatory activitiesSymptom controlParietal cortex regionsClinical effectsFunction recoverySymptom alleviationMotor impairmentSubcortical regionsCovarying patterns of white matter lesions and cortical atrophy predict progression in early MS
Muthuraman M, Fleischer V, Kroth J, Ciolac D, Radetz A, Koirala N, Gonzalez-Escamilla G, Wiendl H, Meuth S, Zipp F, Groppa S. Covarying patterns of white matter lesions and cortical atrophy predict progression in early MS. Neurology Neuroimmunology & Neuroinflammation 2020, 7: e681. PMID: 32024782, PMCID: PMC7051213, DOI: 10.1212/nxi.0000000000000681.Peer-Reviewed Original ResearchConceptsCortical atrophyDisability progressionLesion distributionWM lesionsEarly relapsing-remitting MSShort-term disability progressionWhite matter lesion distributionDisability Status Scale scoreRapid clinical deteriorationRelapsing-remitting MSStatus Scale scoreWhite matter lesionsIndividual patient outcomesLeft-lateralized patternClinical worseningClinical deteriorationClinical disabilityFunctional disabilityStudy cohortMatter lesionsEarly MSPatient outcomesHigh riskIndependent cohortSecond cohort
2019
Gray matter integrity predicts white matter network reorganization in multiple sclerosis
Radetz A, Koirala N, Krämer J, Johnen A, Fleischer V, Gonzalez‐Escamilla G, Cerina M, Muthuraman M, Meuth S, Groppa S. Gray matter integrity predicts white matter network reorganization in multiple sclerosis. Human Brain Mapping 2019, 41: 917-927. PMID: 32026599, PMCID: PMC7268008, DOI: 10.1002/hbm.24849.Peer-Reviewed Original ResearchConceptsDeep gray matter volumesGray matter volumeMultiple sclerosisGray matter integrityMatter volumeWhite matter networksEarly relapsing-remitting multiple sclerosisRelapsing-remitting multiple sclerosisTime pointsGray matter atrophyDeep gray matter structuresCognitive performanceMiddle temporal cortexGray matter structuresGray matter regionsDisability progressionBrain stemMatter damageSignificant atrophyMatter atrophyDeep gray matter regionsCortical thicknessTemporal cortexTissue damageAtrophyInterictal Hyperperfusion in the Higher Visual Cortex in Patients With Episodic Migraine
Michels L, Villanueva J, O’Gorman R, Muthuraman M, Koirala N, Büchler R, Gantenbein A, Sandor P, Luechinger R, Kollias S, Riederer F. Interictal Hyperperfusion in the Higher Visual Cortex in Patients With Episodic Migraine. Headache The Journal Of Head And Face Pain 2019, 59: 1808-1820. PMID: 31680242, DOI: 10.1111/head.13646.Peer-Reviewed Original ResearchConceptsCerebral blood flowCohen's d effect sizesEpisodic migraineD effect sizesHealthy controlsSuperior temporal gyrusASL-MRIVisual cortexInterictal cerebral blood flowInterictal stateTemporal gyrusHigher-order visual cortexNeuro-functional abnormalitiesEffect sizeFunctional brain imaging studiesNon-invasive imaging methodMagnetic resonance imagingHigher visual cortexBrain imaging studiesInterictal hyperperfusionCBF changesSubcortical alterationsMigraine pathophysiologyParietal operculumBlood flowCortical network fingerprints predict deep brain stimulation outcome in dystonia
Gonzalez‐Escamilla G, Muthuraman M, Reich M, Koirala N, Riedel C, Glaser M, Lange F, Deuschl G, Volkmann J, Groppa S. Cortical network fingerprints predict deep brain stimulation outcome in dystonia. Movement Disorders 2019, 34: 1537-1546. PMID: 31433874, DOI: 10.1002/mds.27808.Peer-Reviewed Original ResearchConceptsDeep brain stimulationModerate-outcome groupDystonia patientsEffective evidence-based therapySuperior-outcome groupGlobus pallidus internusGrey matter atrophy patternsEvidence-based therapiesBrain network organizationClinical responseCortical atrophyDBS outcomesIndependent predictorsMotor improvementMulticenter cohortDBS implantationAtrophy patternsPreoperative MRITherapy responseVisuomotor areasCortical thicknessBrain stimulationCortical mantlePatientsUnequivocal predictorsSelective Brain Network and Cellular Responses Upon Dimethyl Fumarate Immunomodulation in Multiple Sclerosis
Ciolac D, Luessi F, Gonzalez-Escamilla G, Koirala N, Riedel C, Fleischer V, Bittner S, Krämer J, Meuth S, Muthuraman M, Groppa S. Selective Brain Network and Cellular Responses Upon Dimethyl Fumarate Immunomodulation in Multiple Sclerosis. Frontiers In Immunology 2019, 10: 1779. PMID: 31417557, PMCID: PMC6682686, DOI: 10.3389/fimmu.2019.01779.Peer-Reviewed Original ResearchConceptsCortical atrophyDisease activityMultiple sclerosisDMF groupDeep GM volumesDimethyl fumarate treatmentT-cell depletionDisease-modifying drugsWhite matter damageImmune cell dynamicsDMF therapyNAT patientsStrong CD8Lymphocyte subsetsDisease durationDisease courseMS patientsCell depletionMatter damageLess atrophyFumarate treatmentTreatment paradigmBrain network responsesLesion volumeTherapy responseLarge-scale network architecture and associated structural cortico-subcortical abnormalities in patients with sleep/awake-related seizures
Chiosa V, Ciolac D, Groppa S, Koirala N, Pintea B, Vataman A, Winter Y, Gonzalez-Escamilla G, Muthuraman M, Groppa S. Large-scale network architecture and associated structural cortico-subcortical abnormalities in patients with sleep/awake-related seizures. Sleep 2019, 42: zsz006. PMID: 30753617, DOI: 10.1093/sleep/zsz006.Peer-Reviewed Original ResearchConceptsAwake seizuresSleep seizuresHealthy controlsAwake stateSex-matched healthy controlsRight middle temporal cortexDifferent epilepsy typesVolume of hippocampusBrain networksMiddle temporal cortexEpilepsy typePathophysiological alterationsSubcortical abnormalitiesPatientsTemporal cortexSeizuresSubcortical regionsSuperior temporalBilateral insulaOrbitofrontal cortexSleepParietal regionsAbnormalitiesRight hemisphereStructural correlates
2018
Cerebello-cortical network fingerprints differ between essential, Parkinson’s and mimicked tremors
Muthuraman M, Raethjen J, Koirala N, Anwar A, Mideksa K, Elble R, Groppa S, Deuschl G. Cerebello-cortical network fingerprints differ between essential, Parkinson’s and mimicked tremors. Brain 2018, 141: 1770-1781. PMID: 29701820, DOI: 10.1093/brain/awy098.Peer-Reviewed Original ResearchConceptsEssential tremorSensorimotor cortexCerebral cortexHealthy controlsPremotor cortexParkinson's diseaseVoluntary rhythmic movementsPrimary sensorimotor cortexSex-matched groupPrimary sensorimotor regionsEEG-EMG coherenceMotor performance measuresParkinson's tremorEMG oscillationsCortical efferentsSensorimotor regionsCerebellar involvementTremor severityFunctional MRICortexCerebellumDiseaseAdditional studiesTremorMulti-channel EMG
2017
Increased cerebrospinal fluid albumin and immunoglobulin A fractions forecast cortical atrophy and longitudinal functional deterioration in relapsing-remitting multiple sclerosis
Kroth J, Ciolac D, Fleischer V, Koirala N, Krämer J, Muthuraman M, Luessi F, Bittner S, Gonzalez-Escamilla G, Zipp F, Meuth S, Groppa S. Increased cerebrospinal fluid albumin and immunoglobulin A fractions forecast cortical atrophy and longitudinal functional deterioration in relapsing-remitting multiple sclerosis. Multiple Sclerosis Journal 2017, 25: 338-343. PMID: 29226779, DOI: 10.1177/1352458517748474.Peer-Reviewed Original ResearchConceptsMultiple sclerosisCortical atrophyRelapsing-remitting multiple sclerosisBlood-brain barrier integrityLongitudinal magnetic resonance imagingCerebrospinal fluid markersGray matter pathologyHigher functional disabilityCerebrospinal fluid albuminQuotient of albuminMagnetic resonance imagingCumulative disabilityClinical disabilityWidespread atrophyFunctional disabilityCSF concentrationsCSF markersDisease progressionFunctional deteriorationImmunoglobulin AAtrophy measurementsFluid markersUnequivocal predictorsBarrier integrityDisease evolutionFrontal Lobe Connectivity and Network Community Characteristics are Associated with the Outcome of Subthalamic Nucleus Deep Brain Stimulation in Patients with Parkinson’s Disease
Koirala N, Fleischer V, Glaser M, Zeuner K, Deuschl G, Volkmann J, Muthuraman M, Groppa S. Frontal Lobe Connectivity and Network Community Characteristics are Associated with the Outcome of Subthalamic Nucleus Deep Brain Stimulation in Patients with Parkinson’s Disease. Brain Topography 2017, 31: 311-321. PMID: 28986718, DOI: 10.1007/s10548-017-0597-4.Peer-Reviewed Original ResearchConceptsDeep brain stimulationDiffusion-weighted imagingPostoperative clinical outcomesClinical responseParkinson's diseaseSTN-DBSClinical outcomesSubthalamic nucleusBrain stimulationSubthalamic nucleus deep brain stimulationNon-motor symptomsOptimal clinical responseConnectivity profilesPre-intervention predictorsEvidence-based stateIndependent predictorsPD patientsTherapy optionsClinical effectivenessCingulate gyrusFrontal lobe connectivityCerebral regionsT MRI scannerCerebral networksPrefrontal cortexBreakdown of Thalamo-Cortical Connectivity Precedes Spike Generation in Focal Epilepsies
Chiosa V, Groppa S, Ciolac D, Koirala N, Mişina L, Winter Y, Moldovanu M, Muthuraman M, Groppa S. Breakdown of Thalamo-Cortical Connectivity Precedes Spike Generation in Focal Epilepsies. Brain Connectivity 2017, 7: 309-320. PMID: 28494616, DOI: 10.1089/brain.2017.0487.Peer-Reviewed Original ResearchConceptsFrontal lobeVentral anterior nucleusThalamo-cortical connectivityFuture therapeutic approachesSpike generationFocal epileptic seizuresMedial dorsalThalamic volumeFocal epilepsyAnterior nucleusFrontal cortexTherapeutic approachesEpileptic seizuresCerebral networksCortical integrityThalamusEEG recordingsWidespread areasDistinct patternsLobeEpileptogenesisPatientsEpilepsySeizuresCortexCombining transcranial magnetic stimulation and subdural electrodes for pain modulation
Chirumamilla V, Koirala N, Groppa S. Combining transcranial magnetic stimulation and subdural electrodes for pain modulation. Clinical Neurophysiology 2017, 128: 1041-1042. PMID: 28359653, DOI: 10.1016/j.clinph.2017.03.003.Peer-Reviewed Original Research