2024
Mapping the structure-function relationship along macroscale gradients in the human brain
Collins E, Chishti O, Obaid S, McGrath H, King A, Shen X, Arora J, Papademetris X, Constable R, Spencer D, Zaveri H. Mapping the structure-function relationship along macroscale gradients in the human brain. Nature Communications 2024, 15: 7063. PMID: 39152127, PMCID: PMC11329792, DOI: 10.1038/s41467-024-51395-6.Peer-Reviewed Original Research
2021
Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain
Ong C, Damisah EC, Gruenbaum SE, Dhaher R, Deng Y, Sandhu MRS, Zaveri HP, Spencer DD, Eid T. Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain. Epilepsia 2021, 62: e88-e97. PMID: 33949690, PMCID: PMC11259155, DOI: 10.1111/epi.16920.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAmino Acids, Branched-ChainBrain ChemistryChildChild, PreschoolChromatography, High Pressure LiquidDrug Resistant EpilepsyElectrocorticographyElectroencephalographyEpilepsies, PartialExtracellular SpaceFemaleGlutamic AcidHumansIsoleucineMaleMicrodialysisMiddle AgedSeizuresTandem Mass SpectrometryYoung AdultConceptsSpontaneous seizuresDrug-resistant focal epilepsyExtracellular brain glutamateHuman epileptic brainBranched-chain amino acidsBranched chain amino acids valineRefractory epilepsyBrain microdialysisGlutamatergic neurotransmissionFocal epilepsySeizure onsetBrain glutamateEpileptic brainHuman patientsSeizuresBrain regionsDialysis samplesMammalian targetEpilepsyLiquid chromatography-tandem mass spectrometryBaselineBCAAIntracranial electroencephalographyChromatography-tandem mass spectrometryPatientsNetwork-Related Changes in Neurotransmitters and Seizure Propagation During Rodent Epileptogenesis
Dhaher R, Gruenbaum SE, Sandhu MRS, Ottestad-Hansen S, Tu N, Wang Y, Lee TW, Deshpande K, Spencer DD, Danbolt NC, Zaveri HP, Eid T. Network-Related Changes in Neurotransmitters and Seizure Propagation During Rodent Epileptogenesis. Neurology 2021, 96: e2261-e2271. PMID: 33722994, PMCID: PMC8166437, DOI: 10.1212/wnl.0000000000011846.Peer-Reviewed Original ResearchConceptsSpontaneous seizuresSeizure propagationSeizure focusMesial temporal lobe epilepsyExtracellular brain levelsTemporal lobe epilepsyExtracellular glutamate levelsRelevant rodent modelsGlutamine synthetase inhibitor methionine sulfoximineTransporter subtype 1Contralateral hippocampusLobe epilepsyBrain levelsBrain microdialysisExtracellular GABANeurotransmitter levelsSeizure initiationGlutamate levelsSeizure onsetEpilepsy networkRodent modelsSubtype 1EpileptogenesisHippocampusBrain regions
2020
Beyond implantation effect? Long-term seizure reduction and freedom following intracranial monitoring without additional surgical interventions
Percy J, Zaveri H, Duckrow RB, Gerrard J, Farooque P, Hirsch LJ, Spencer DD, Sivaraju A. Beyond implantation effect? Long-term seizure reduction and freedom following intracranial monitoring without additional surgical interventions. Epilepsy & Behavior 2020, 111: 107231. PMID: 32615416, DOI: 10.1016/j.yebeh.2020.107231.Peer-Reviewed Original ResearchConceptsLong-term seizure freedomSeizure freedomSeizure frequencyElectrode implantationIntracranial studiesLong-term seizure reductionAdditional surgical interventionSeizure onset localizationIntracranial electroencephalogram monitoringSeizure reductionConsecutive patientsSurgical interventionEpileptogenic networksElectroencephalogram monitoringNeuromodulatory effectsRetrospective analysisIntracranial monitoringTransient improvementDepth electrodesPatientsYear 4ImplantationAdequate dataYearsOral glutamine supplementation increases seizure severity in a rodent model of mesial temporal lobe epilepsy
Dhaher R, Chen EC, Perez E, Rapuano A, Sandhu MRS, Gruenbaum SE, Deshpande K, Dai F, Zaveri HP, Eid T. Oral glutamine supplementation increases seizure severity in a rodent model of mesial temporal lobe epilepsy. Nutritional Neuroscience 2020, 25: 64-69. PMID: 31900092, PMCID: PMC8970572, DOI: 10.1080/1028415x.2019.1708568.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyOral glutamine supplementationSeverity of seizuresTemporal lobe epilepsyGlutamine supplementationSeizure severityLobe epilepsyRefractory mesial temporal lobe epilepsyMale Sprague-DawleySeizure frequencyConvulsive seizuresSeizure propagationEpilepsy modelSprague-DawleyEffective treatmentRodent modelsSeizuresSupplementationSeverityPotential roleEpilepsyFunction mutationsHippocampusGlutamine synthetaseDays
2019
Slowing less than 1 Hz is decreased near the seizure onset zone
Lundstrom BN, Boly M, Duckrow R, Zaveri HP, Blumenfeld H. Slowing less than 1 Hz is decreased near the seizure onset zone. Scientific Reports 2019, 9: 6218. PMID: 30996228, PMCID: PMC6470162, DOI: 10.1038/s41598-019-42347-y.Peer-Reviewed Original ResearchConceptsSeizure onset zoneOnset zoneFocal slowingFocal cerebral dysfunctionLocation of dysfunctionFocal epilepsy patientsSlow wave activitySlow oscillationsLocal synaptic strengthsSlow oscillation activityCerebral dysfunctionReduced inhibitory activityPostictal statePostictal slowingEpilepsy patientsModulatory effectsSynaptic strengthDelta frequencyCortical mechanismsIntracranial recordingsDistinct neural mechanismsIntracranial electroencephalographyNeural mechanismsDysfunctionSleep
2018
Resting state connectivity in neocortical epilepsy: The epilepsy network as a patient-specific biomarker
Marino AC, Yang GJ, Tyrtova E, Wu K, Zaveri HP, Farooque P, Spencer DD, Bandt SK. Resting state connectivity in neocortical epilepsy: The epilepsy network as a patient-specific biomarker. Clinical Neurophysiology 2018, 130: 280-288. PMID: 30605890, DOI: 10.1016/j.clinph.2018.11.016.Peer-Reviewed Original ResearchConceptsLocalization related epilepsyEpilepsy networkSeizure onset locationSingle-patient levelCorrelated network activityPatient-specific biomarkersRelated epilepsyConnectivity patternsNeocortical epilepsyPatient levelSeizure onsetInterictal periodAnatomic locationPatientsPossible biomarkersState connectivityCortical regionsSingle-subject levelTopographic distributionCohortNetwork disorderBrain networksEpilepsyNetwork activityBiomarkersSeizure susceptibility and infraslow modulatory activity in the intracranial electroencephalogram
Joshi RB, Duckrow RB, Goncharova II, Gerrard JL, Spencer DD, Hirsch LJ, Godwin DW, Zaveri HP. Seizure susceptibility and infraslow modulatory activity in the intracranial electroencephalogram. Epilepsia 2018, 59: 2075-2085. PMID: 30187919, DOI: 10.1111/epi.14559.Peer-Reviewed Original ResearchConceptsAED taperYale-New Haven HospitalAdult epilepsy patientsSeizure forecasting algorithmsElectrode contact pairsSeizure onset areaSeizure susceptibilityClinical recordsDrug taperElectrophysiological changesEpilepsy patientsIntracranial electroencephalographic dataMagnitude-squared coherenceModulatory activitySeizuresPatientsOnset areaPreseizurePostseizureProgressive desynchronizationIntracranial electroencephalogramDaysIctogenesisEffect of timeHospital
2017
Disruption of Brain–Heart Coupling in Sepsis
Admiraal MM, Gilmore EJ, Van Putten MJAM, Zaveri HP, Hirsch LJ, Gaspard N. Disruption of Brain–Heart Coupling in Sepsis. Journal Of Clinical Neurophysiology 2017, 34: 413-420. PMID: 28520632, DOI: 10.1097/wnp.0000000000000381.Peer-Reviewed Original ResearchNetwork evolution in mesial temporal lobe epilepsy revealed by diffusion tensor imaging
Wang H, Huang Y, Coman D, Munbodh R, Dhaher R, Zaveri HP, Hyder F, Eid T. Network evolution in mesial temporal lobe epilepsy revealed by diffusion tensor imaging. Epilepsia 2017, 58: 824-834. PMID: 28378878, PMCID: PMC5429866, DOI: 10.1111/epi.13731.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyDiffusion tensor imagingTemporal lobe epilepsyFractional anisotropyLobe epilepsyAstroglial glutamine synthetaseEntorhinal-hippocampal areaEpileptogenic hippocampal formationNumerous brain regionsMultiple brain areasBrain diffusion tensor imagingLater time pointsInfused ratsEpileptogenic processCorpus callosumEpileptogenesisHippocampal formationBrain areasImaging biomarkersEarly identificationBrain regionsRatsTensor imagingFA changesTime points
2016
Progressive neuronal activation accompanies epileptogenesis caused by hippocampal glutamine synthetase inhibition
Albright B, Dhaher R, Wang H, Harb R, Lee TW, Zaveri H, Eid T. Progressive neuronal activation accompanies epileptogenesis caused by hippocampal glutamine synthetase inhibition. Experimental Neurology 2016, 288: 122-133. PMID: 27769717, PMCID: PMC5547560, DOI: 10.1016/j.expneurol.2016.10.007.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyNeuronal activationHippocampal formationHuman mesial temporal lobe epilepsyAnterior olfactory areaEntorhinal-hippocampal areaProcess of epileptogenesisC-Fos immunohistochemistryTemporal lobe epilepsyTypes of seizuresGlutamine synthetase inhibitionSurgical resectionPiriform cortexSeizure severityLobe epilepsyHippocampal astrocytesEpilepsy developmentEpileptogenic processElectroencephalogram monitoringOlfactory areasPharmacological interventionsSeizure phenotypeBed nucleusMidline thalamusStria terminalisRegional and network relationship in the intracranial EEG second spectrum
Joshi RB, Gaspard N, Goncharova II, Duckrow RB, Duncan D, Gerrard JL, Spencer DD, Hirsch LJ, Zaveri HP. Regional and network relationship in the intracranial EEG second spectrum. Clinical Neurophysiology 2016, 127: 3485-3491. PMID: 27692590, DOI: 10.1016/j.clinph.2016.09.003.Peer-Reviewed Original ResearchThe relationship between seizures, interictal spikes and antiepileptic drugs
Goncharova II, Alkawadri R, Gaspard N, Duckrow RB, Spencer DD, Hirsch LJ, Spencer SS, Zaveri HP. The relationship between seizures, interictal spikes and antiepileptic drugs. Clinical Neurophysiology 2016, 127: 3180-3186. PMID: 27292227, DOI: 10.1016/j.clinph.2016.05.014.Peer-Reviewed Original ResearchConceptsFirst seizureSeizure occurrenceAED taperSpike rateEEG monitoringMarker of inhibitionIntracranial EEG monitoringOccurrence of seizuresScalp EEG monitoringConsecutive patientsAntiepileptic drugsDrug taperHigh spike ratesInterictal spikesSeizuresDay 4Intracranial electrodesPatientsAEDsSignificant relationshipProgressive change in sleep over multiple nights of intracranial EEG monitoring
Joshi RB, Gaspard N, Goncharova II, Pavlova M, Duckrow RB, Gerrard JL, Spencer DD, Hirsch LJ, Zaveri HP. Progressive change in sleep over multiple nights of intracranial EEG monitoring. Clinical Neurophysiology 2016, 127: 2302-2307. PMID: 27072103, DOI: 10.1016/j.clinph.2016.02.018.Peer-Reviewed Original Research50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate
Cavus I, Widi GA, Duckrow RB, Zaveri H, Kennard JT, Krystal J, Spencer DD. 50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate. Epilepsia 2016, 57: 288-297. PMID: 26749134, DOI: 10.1111/epi.13269.Peer-Reviewed Original ResearchConceptsBasal glutamate levelsRefractory epilepsyGlutamate effluxBasal glutamateGlutamate levelsElectrical stimulationEpileptic hippocampusGlutamate releaseSeizure groupHz stimulationBrain glutamate releaseHippocampus of patientsStimulation-induced increaseEpilepsy monitoring unitStimulation-induced changesEpileptogenic hippocampusInduced seizuresSeizure inductionSpontaneous seizuresInterictal levelsGlutamate increaseAtrophic hippocampusElectroencephalography evaluationHippocampal stimulationHippocampal electrodes
2015
A comparison of the power spectral density of scalp EEG and subjacent electrocorticograms
Petroff OA, Spencer DD, Goncharova II, Zaveri HP. A comparison of the power spectral density of scalp EEG and subjacent electrocorticograms. Clinical Neurophysiology 2015, 127: 1108-1112. PMID: 26386645, DOI: 10.1016/j.clinph.2015.08.004.Peer-Reviewed Original ResearchInhibition of glutamine synthetase in the central nucleus of the amygdala induces anhedonic behavior and recurrent seizures in a rat model of mesial temporal lobe epilepsy
Gruenbaum SE, Wang H, Zaveri HP, Tang AB, Lee TS, Eid T, Dhaher R. Inhibition of glutamine synthetase in the central nucleus of the amygdala induces anhedonic behavior and recurrent seizures in a rat model of mesial temporal lobe epilepsy. Epilepsy & Behavior 2015, 51: 96-103. PMID: 26262937, PMCID: PMC4663049, DOI: 10.1016/j.yebeh.2015.07.015.Peer-Reviewed Original ResearchMeSH KeywordsAmygdalaAnalysis of VarianceAnhedoniaAnimalsBrainCentral Amygdaloid NucleusComorbidityDepressive DisorderDisease Models, AnimalElectroencephalographyEnzyme InhibitorsEpilepsy, Temporal LobeGlutamate-Ammonia LigaseHippocampusMaleMethionine SulfoximineNeuronsRatsRats, Sprague-DawleySeizuresConceptsMesial temporal lobe epilepsyTemporal lobe epilepsyRecurrent seizuresLobe epilepsyCentral nucleusMale Sprague-Dawley ratsPrevalence of depressionSprague-Dawley ratsGlutamine synthetase inhibitor methionine sulfoximineMeasures of anhedoniaRight CeA.Seizure activityAnhedonic behaviorDentate gyrusMedial amygdalaSucrose preferenceRat modelCommon causeAstrocytic enzymeBasolateral amygdalaLateral amygdalaOsmotic pumpPatientsEpilepsyAmygdalaDelta rhythm in wakefulness: evidence from intracranial recordings in human beings
Sachdev RN, Gaspard N, Gerrard JL, Hirsch LJ, Spencer DD, Zaveri HP. Delta rhythm in wakefulness: evidence from intracranial recordings in human beings. Journal Of Neurophysiology 2015, 114: 1248-1254. PMID: 26084904, PMCID: PMC4725112, DOI: 10.1152/jn.00249.2015.Peer-Reviewed Original ResearchEffects of site-specific infusions of methionine sulfoximine on the temporal progression of seizures in a rat model of mesial temporal lobe epilepsy
Dhaher R, Wang H, Gruenbaum SE, Tu N, Lee TS, Zaveri HP, Eid T. Effects of site-specific infusions of methionine sulfoximine on the temporal progression of seizures in a rat model of mesial temporal lobe epilepsy. Epilepsy Research 2015, 115: 45-54. PMID: 26220375, PMCID: PMC4677790, DOI: 10.1016/j.eplepsyres.2015.05.005.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyTemporal lobe epilepsyRecurrent seizuresLateral ventricleLobe epilepsyDentate gyrusEntorhinal cortexDeep entorhinal cortexEntorhinal-hippocampal areaWeek recording periodSite-specific infusionPhosphate-buffered salineDays of infusionAdult laboratory ratsRecording periodMethionine sulfoximineSeizure severitySeizure activitySevere seizuresMetabolism of glutamateRat modelSynaptic transmissionAnatomical distributionHippocampal formationAngular bundle
2014
The spatial and signal characteristics of physiologic high frequency oscillations
Alkawadri R, Gaspard N, Goncharova II, Spencer DD, Gerrard JL, Zaveri H, Duckrow RB, Blumenfeld H, Hirsch LJ. The spatial and signal characteristics of physiologic high frequency oscillations. Epilepsia 2014, 55: 1986-1995. PMID: 25470216, PMCID: PMC5123742, DOI: 10.1111/epi.12851.Peer-Reviewed Original ResearchConceptsPhysiologic high-frequency oscillationsSeizure onsetEpileptic networkNon-rapid eye movement sleepComprehensive Epilepsy CenterMesial temporal structuresEye movement sleepHighest HFO ratesHigh-frequency oscillationsFirst seizureInvasive evaluationEpilepsy centersIntracranial evaluationMovement sleepPerirolandic regionEpileptiform dischargesParietooccipital regionOccipital lobeEpileptic sitesPatientsNonepileptic regionsPhysiologic eventsFast ripplesHFO ratesLonger duration