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 spectrometryPatients
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 dataYears
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
2016
Regional 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 ResearchMeSH KeywordsAdolescentAdultBrainBrain MappingElectroencephalographyEpilepsyFemaleHumansMaleMiddle AgedSleepYoung Adult50 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 ResearchDelta 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 Research
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 durationIctal spread of medial temporal lobe seizures with and without secondary generalization: An intracranial electroencephalography analysis
Yoo JY, Farooque P, Chen WC, Youngblood MW, Zaveri HP, Gerrard JL, Spencer DD, Hirsch LJ, Blumenfeld H. Ictal spread of medial temporal lobe seizures with and without secondary generalization: An intracranial electroencephalography analysis. Epilepsia 2014, 55: 289-295. PMID: 24417694, PMCID: PMC4103687, DOI: 10.1111/epi.12505.Peer-Reviewed Original ResearchConceptsSecondary generalizationTemporal lobe seizuresFocal seizuresTemporal cortexMedial temporal lobe seizuresCortical regionsLow-voltage fast activityProminent activationAnteromedial temporal lobe resectionTonic-clonic seizuresSeizure-onset patternsTemporal lobe resectionLateral temporal cortexQuality of lifePosterior lateral temporal cortexTemporal lobe areasIntracranial electroencephalography studyMedial temporal lobe areasMedial temporal lobePosterior lateral temporal regionsIctal spreadHippocampal sclerosisSeizure spreadLobe resectionTemporal lobe
2013
Intracranially recorded interictal spikes: Relation to seizure onset area and effect of medication and time of day
Goncharova II, Spencer SS, Duckrow RB, Hirsch LJ, Spencer DD, Zaveri HP. Intracranially recorded interictal spikes: Relation to seizure onset area and effect of medication and time of day. Clinical Neurophysiology 2013, 124: 2119-2128. PMID: 23856192, DOI: 10.1016/j.clinph.2013.05.027.Peer-Reviewed Original ResearchIntracranial EEG evaluation of relationship within a resting state network
Duncan D, Duckrow RB, Pincus SM, Goncharova I, Hirsch LJ, Spencer DD, Coifman RR, Zaveri HP. Intracranial EEG evaluation of relationship within a resting state network. Clinical Neurophysiology 2013, 124: 1943-1951. PMID: 23790525, DOI: 10.1016/j.clinph.2013.03.028.Peer-Reviewed Original ResearchConceptsDefault mode networkIntracranial EEG evaluationMode networkLocalization-related epilepsyCross-approximate entropyNeuronal involvementHemodynamic measurementsIntracranial EEG recordingsEEG evaluationBackground activityGamma powerFMRI studyIntracranial EEGBrain activityPatientsEEG recordingsLow levelsT2EpilepsyMagnitude squared coherenceT1
2010
Impaired consciousness in temporal lobe seizures: role of cortical slow activity
Englot DJ, Yang L, Hamid H, Danielson N, Bai X, Marfeo A, Yu L, Gordon A, Purcaro MJ, Motelow JE, Agarwal R, Ellens DJ, Golomb JD, Shamy MC, Zhang H, Carlson C, Doyle W, Devinsky O, Vives K, Spencer DD, Spencer SS, Schevon C, Zaveri HP, Blumenfeld H. Impaired consciousness in temporal lobe seizures: role of cortical slow activity. Brain 2010, 133: 3764-3777. PMID: 21081551, PMCID: PMC2995886, DOI: 10.1093/brain/awq316.Peer-Reviewed Original ResearchConceptsTemporal lobe seizuresSlow wave activityTemporal lobe epilepsySimple partial seizuresSubcortical arousal systemsImpaired consciousnessSeizure activityTemporal lobeLobe epilepsyArousal systemCortical functionFocal temporal lobe seizuresHz slow wave activityMesial temporal lobe epilepsyCortical slow activityDepressed cortical functionNetwork inhibition hypothesisTemporal lobe disordersComplex partial seizuresBilateral temporal lobesLanguage-dominant temporal lobeSlow wavesCortical-subcortical networksPowerful inhibitory effectIntracranial electroencephalography recordingsPatient and caregiver perspectives on seizure prediction
Arthurs S, Zaveri HP, Frei MG, Osorio I. Patient and caregiver perspectives on seizure prediction. Epilepsy & Behavior 2010, 19: 474-477. PMID: 20851054, DOI: 10.1016/j.yebeh.2010.08.010.Peer-Reviewed Original Research