2010
The interplay of cannabinoid and NMDA glutamate receptor systems in humans: Preliminary evidence of interactive effects of cannabidiol and ketamine in healthy human subjects
Hallak JE, Dursun SM, Bosi DC, de Macedo LR, Machado-de-Sousa JP, Abrão J, Crippa JA, McGuire P, Krystal JH, Baker GB, Zuardi AW. The interplay of cannabinoid and NMDA glutamate receptor systems in humans: Preliminary evidence of interactive effects of cannabidiol and ketamine in healthy human subjects. Progress In Neuro-Psychopharmacology And Biological Psychiatry 2010, 35: 198-202. PMID: 21062637, DOI: 10.1016/j.pnpbp.2010.11.002.Peer-Reviewed Original ResearchConceptsBrief Psychiatric Rating ScaleHealthy human subjectsGlutamate receptor systemMale healthy volunteersNMDA receptor antagonistEffects of ketamineTreatment of schizophreniaPsychiatric Rating ScaleHuman subjectsWeak partial agonistNon-significant trendKetamine administrationReceptor antagonistEndocannabinoid systemHealthy volunteersPartial agonistActivation subscalePsychiatric conditionsKetamineRandomized orderReceptor systemBehavioral effectsRating ScaleCannabidiolPreliminary evidence
2005
Preliminary evidence for persistent abnormalities in amygdala volumes in adolescents and young adults with bipolar disorder
Blumberg HP, Fredericks C, Wang F, Kalmar JH, Spencer L, Papademetris X, Pittman B, Martin A, Peterson BS, Fulbright RK, Krystal JH. Preliminary evidence for persistent abnormalities in amygdala volumes in adolescents and young adults with bipolar disorder. Bipolar Disorders 2005, 7: 570-576. PMID: 16403182, PMCID: PMC2291299, DOI: 10.1111/j.1399-5618.2005.00264.x.Peer-Reviewed Original ResearchConceptsAmygdala volumeBipolar disorderYoung adultsAmygdala volume abnormalitiesTotal brain volumeHigh-resolution magnetic resonancePreliminary evidenceSubjects longitudinal designPersistent abnormalitiesMixed-model statistical analysisBD IVolume abnormalitiesHealthy comparison participantsBrain volumeHealthy participantsAbnormalitiesAdultsAdolescentsComparison participantsAmygdalaDevelopmental epochsDisordersLongitudinal designParticipantsMagnetic resonancePreliminary evidence for medication effects on functional abnormalities in the amygdala and anterior cingulate in bipolar disorder
Blumberg HP, Donegan NH, Sanislow CA, Collins S, Lacadie C, Skudlarski P, Gueorguieva R, Fulbright RK, McGlashan TH, Gore JC, Krystal JH. Preliminary evidence for medication effects on functional abnormalities in the amygdala and anterior cingulate in bipolar disorder. Psychopharmacology 2005, 183: 308-313. PMID: 16249909, DOI: 10.1007/s00213-005-0156-7.Peer-Reviewed Original ResearchConceptsUnmedicated bipolar disorderMood-stabilizing medicationsBipolar disorderBD participantsPotential treatment targetMagnetic resonance imagingPreliminary evidenceMethodsFunctional magnetic resonance imagingAnterior cingulate activationResultsThe groupMedication effectsFunctional abnormalitiesHealthy comparison participantsObjectivesThe aimAnterior cingulateTreatment targetsResonance imagingMedicationsHC participantsAmygdala activationCingulate activationAmygdala increasesComparison participantsEmotional stimuliAbnormalities
2004
Preliminary evidence of attenuation of the disruptive effects of the NMDA glutamate receptor antagonist, ketamine, on working memory by pretreatment with the group II metabotropic glutamate receptor agonist, LY354740, in healthy human subjects
Krystal JH, Abi-Saab W, Perry E, D’Souza D, Liu N, Gueorguieva R, McDougall L, Hunsberger T, Belger A, Levine L, Breier A. Preliminary evidence of attenuation of the disruptive effects of the NMDA glutamate receptor antagonist, ketamine, on working memory by pretreatment with the group II metabotropic glutamate receptor agonist, LY354740, in healthy human subjects. Psychopharmacology 2004, 179: 303-309. PMID: 15309376, DOI: 10.1007/s00213-004-1982-8.Peer-Reviewed Original ResearchConceptsGroup II metabotropic glutamate receptor agonistMetabotropic glutamate receptor agonistHealthy human subjectsNMDA glutamate receptor antagonistGlutamate receptor agonistsGlutamate receptor antagonistsTest dayCognitive effectsPerceptual changesKetamine infusionReceptor antagonistReceptor agonistDysphoric moodMemory impairmentBehavioral consequencesSignificant dose-related improvementGroup II mGluR agonistReceptor functionHuman subjectsMemoryNegative symptomsDose-related improvementNMDA receptor functionPreliminary evidenceDisruptive effects
2003
Preliminary evidence of hippocampal dysfunction in adolescent MDMA (“ecstasy”) users: possible relationship to neurotoxic effects
Jacobsen LK, Mencl WE, Pugh KR, Skudlarski P, Krystal JH. Preliminary evidence of hippocampal dysfunction in adolescent MDMA (“ecstasy”) users: possible relationship to neurotoxic effects. Psychopharmacology 2003, 173: 383-390. PMID: 14647960, DOI: 10.1007/s00213-003-1679-4.Peer-Reviewed Original ResearchConceptsFunctional magnetic resonance imagingMDMA usersCognitive deficitsMDMA useBrain functionDivided attentionMemory taskMemory loadResultsMDMA usersLeft hippocampusHippocampal dysfunctionSubstance useCognitive impairmentAdolescencePreliminary evidenceReaction timeDevelopmental impactPilot sampleDeficitsMDMAMagnetic resonance imagingIQAttentionMemoryHippocampus
1999
Preliminary Evidence of Low Cortical GABA Levels in Localized 1H-MR Spectra of Alcohol-Dependent and Hepatic Encephalopathy Patients
Behar KL, Rothman DL, Petersen KF, Hooten M, Delaney R, Petroff OA, Shulman GI, Navarro V, Petrakis IL, Charney DS, Krystal JH. Preliminary Evidence of Low Cortical GABA Levels in Localized 1H-MR Spectra of Alcohol-Dependent and Hepatic Encephalopathy Patients. American Journal Of Psychiatry 1999, 156: 952-954. PMID: 10360140, DOI: 10.1176/ajp.156.6.952.Peer-Reviewed Original ResearchConceptsHepatic encephalopathy patientsEncephalopathy patientsGamma-aminobutyric acidHealthy subjectsCortical GABA levelsGABA-ergic systemDetoxified alcohol-dependent patientsAlcohol-dependent patientsNeuroactive amino acidsCerebral cortexGABA levelsOccipital cortexPatientsMetabolite levelsPreliminary evidenceCortexSubjectsLevelsDisease
1996
Preliminary evidence of an association between sensorimotor gating and distractibility in psychosis
Karper LP, Freeman GK, Grillon C, Morgan CA, Charney DS, Krystal JH. Preliminary evidence of an association between sensorimotor gating and distractibility in psychosis. Journal Of Neuropsychiatry 1996, 8: 60-66. PMID: 8845703, DOI: 10.1176/jnp.8.1.60.Peer-Reviewed Original ResearchConceptsSensory gatingChronic psychotic patientsAcoustic startle reflexLateralized attentionImpaired sensory gatingPosner testSensorimotor gatingPsychotic patientsContinuous Performance TestStartle reflexInformation-processing deficitsDistractibility tasksPreliminary evidenceDistractibilityTask scores
1992
Chronic 3,4-Methylenedioxymethamphetamine (MDMA) Use: Effects on Mood and Neuropsychological Function?
Krystal J, Price L, Opsahl C, Ricaurte G, Heninger G. Chronic 3,4-Methylenedioxymethamphetamine (MDMA) Use: Effects on Mood and Neuropsychological Function? The American Journal Of Drug And Alcohol Abuse 1992, 18: 331-341. PMID: 1357957, DOI: 10.3109/00952999209026070.Peer-Reviewed Original ResearchConceptsNeuropsychological functionMDMA useChronic MDMA useWechsler Memory ScaleLeast mild impairmentMemory ScaleNeuropsychological batteryTime of testingMood effectsCognitive functionMemory deficitsMethylenedioxymethamphetamine (MDMA) useDepressed moodMood regulationPreliminary evidenceDeficitsMild impairmentClinical criteriaClinical examinationPreliminary findingsSelective serotoninMoodModerate impairmentAffective disordersPossible detrimental effects