2018
Brain serotonin synthesis capacity in obsessive-compulsive disorder: effects of cognitive behavioral therapy and sertraline
Lissemore J, Sookman D, Gravel P, Berney A, Barsoum A, Diksic M, Nordahl T, Pinard G, Sibon I, Cottraux J, Leyton M, Benkelfat C. Brain serotonin synthesis capacity in obsessive-compulsive disorder: effects of cognitive behavioral therapy and sertraline. Translational Psychiatry 2018, 8: 82. PMID: 29666372, PMCID: PMC5904107, DOI: 10.1038/s41398-018-0128-4.Peer-Reviewed Original ResearchConceptsSerotonin synthesis capacitySelective serotonin reuptake inhibitorsCognitive behavioral therapyObsessive-compulsive disorderPartial respondersTreatment modalitiesMedication-free OCD patientsBehavioral therapyOCD patientsSerotonin reuptake inhibitorsWeeks of treatmentRegional tracer uptakePost-treatment changesPositron emission tomographySynthesis capacityClinical improvementSSRI treatmentReuptake inhibitorsSertraline treatmentSymptom improvementRaphe nucleusNeurochemical changesSerotonergic toneSymptom responseEffective treatment
2017
Posterior dopamine D2/3 receptors and brain network functional connectivity
Nagano‐Saito A, Lissemore J, Gravel P, Leyton M, Carbonell F, Benkelfat C. Posterior dopamine D2/3 receptors and brain network functional connectivity. Synapse 2017, 71 PMID: 28700819, DOI: 10.1002/syn.21993.Peer-Reviewed Original ResearchConceptsDefault mode networkNetwork functional connectivityFunctional connectivity strengthPositron emission tomographyFunctional connectivityPosterior portionReceptor distributionPosteromedial cortexResting-state functional magnetic resonance imagingConnectivity strengthBrain network functional connectivityPosterior default mode networkMode networkDopamine D2/3 receptorsDopamine receptor distributionResting-state connectivityBrain networksFunctional magnetic resonance imagingMagnetic resonance imagingMultiple brain networksFallypride bindingDorsal attention networkMean BPBrain dopamineD2/3 receptors
2014
Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study
Booij L, Soucy J, Young S, Regoli M, Gravel P, Diksic M, Leyton M, Pihl R, Benkelfat C. Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study. Journal Of Neurochemistry 2014, 131: 634-644. PMID: 25041501, DOI: 10.1111/jnc.12826.Peer-Reviewed Original ResearchConceptsMDMA polydrug usersMDMA usePolydrug usersLong-term neurotoxic effectsBrain serotonin synthesisSerotonin synthesis capacityDistal brain regionsNeurotoxicity of MDMAPositron emission tomographySynthesis capacityTracer alphaSerotonin synthesisNeurotoxic effectsPre-frontal regionsTemporal areaBrain regionsEmission tomographyCompensatory mechanismsTryptophan studiesParietal regionsMethylenedioxymethamphetamine (MDMA) useLonger durationBrainstemMDMA users
2013
Grey matter density and GABAA binding potential show a positive linear relationship across cortical regions
Duncan N, Gravel P, Wiebking C, Reader A, Northoff G. Grey matter density and GABAA binding potential show a positive linear relationship across cortical regions. Neuroscience 2013, 235: 226-231. PMID: 23380503, DOI: 10.1016/j.neuroscience.2012.12.075.Peer-Reviewed Original Research
2012
External awareness and GABA—A multimodal imaging study combining fMRI and [18F]flumazenil‐PET
Wiebking C, Duncan N, Qin P, Hayes D, Lyttelton O, Gravel P, Verhaeghe J, Kostikov A, Schirrmacher R, Reader A, Bajbouj M, Northoff G. External awareness and GABA—A multimodal imaging study combining fMRI and [18F]flumazenil‐PET. Human Brain Mapping 2012, 35: 173-184. PMID: 22996793, PMCID: PMC6869063, DOI: 10.1002/hbm.22166.Peer-Reviewed Original ResearchConceptsNeuronal activity changesInhibitory neurotransmitter GABANegative BOLD responseFunctional magnetic resonance imaging paradigmCortical midline regionsSame healthy subjectsGABAA receptorsHealthy subjectsNeurotransmitter GABAPsychiatric disordersBiochemical mechanismsPET imagingExtrinsic systemMidline regionBOLD responseExternal awarenessNeuronal networksUnderlying neuronal networksImaging paradigmGABAActivity changesStimulus typeSame paradigmAwarenessPrecuneus
2011
Brain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder
Berney A, Leyton M, Gravel P, Sibon I, Sookman D, Neto P, Diksic M, Nakai A, Pinard G, Todorov C, Okazawa H, Blier P, Nordahl T, Benkelfat C. Brain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder. JAMA Psychiatry 2011, 68: 732-741. PMID: 21383250, PMCID: PMC3677917, DOI: 10.1001/archgenpsychiatry.2011.16.Peer-Reviewed Original ResearchConceptsL-tryptophan trappingObsessive-compulsive disorderMedication-free patientsHealthy controlsMcGill University Health CentreGlucose metabolic disturbancesAdults meeting criteriaMain outcome measuresUniversity Health CentrePositron emission tomographyDepartment of PsychiatryStatistical parametric mappingTemporal lobe activityMontreal Neurological InstituteSerotonergic componentReuptake inhibitorsSerotonin dysfunctionClinical efficacySerotonergic abnormalitiesMetabolic disturbancesPostsynaptic changesSymptomatic stateSerotonergic systemHealth centersOutcome measures