2022
Associations Between Cannabis Use, Polygenic Liability for Schizophrenia, and Cannabis-related Experiences in a Sample of Cannabis Users
Johnson E, Colbert S, Jeffries P, Tillman R, Bigdeli T, Karcher N, Chan G, Kuperman S, Meyers J, Nurnberger J, Plawecki M, Degenhardt L, Martin N, Kamarajan C, Schuckit M, Murray R, Dick D, Edenberg H, D’Souza D, Di Forti M, Porjesz B, Nelson E, Agrawal A. Associations Between Cannabis Use, Polygenic Liability for Schizophrenia, and Cannabis-related Experiences in a Sample of Cannabis Users. Schizophrenia Bulletin 2022, 49: 778-787. PMID: 36545904, PMCID: PMC10154717, DOI: 10.1093/schbul/sbac196.Peer-Reviewed Original ResearchConceptsCannabis useAlcohol use disorderCognitive difficultiesSchizophrenia polygenic risk scoresFirst cannabis useDaily cannabis useCannabis usersSocial withdrawalUnusual experiencesCannabis involvementPolygenic risk scoresExpected directionGenetic riskUse disordersIndependent replication sampleLike experiencesGenetic liabilityCannabisSchizophreniaPolygenic riskPolygenic liabilityReplication sampleExperienceAnalytic sampleDisorders
2021
Differential Cognitive Performance in Females and Males with Regular Cannabis Use
Martin A, D’Souza D, Newman SD, Hetrick WP, O’Donnell B. Differential Cognitive Performance in Females and Males with Regular Cannabis Use. Journal Of The International Neuropsychological Society 2021, 27: 570-580. PMID: 34261548, PMCID: PMC8830784, DOI: 10.1017/s1355617721000606.Peer-Reviewed Original ResearchConceptsRegular cannabis useCannabis useCognitive measuresPsychomotor speedBiological sexHopkins Verbal Learning TestDifferential cognitive performanceNon-using peersVerbal Learning TestMeasures of intelligenceWechsler Abbreviated ScaleDigit symbol testGreatest group differencesVerbal learningDigit spanLearning TestCognitive performanceAbbreviated ScaleNeurocognitive deficitsCognitive deficitsSymbol testCannabis exposurePsychomotor performanceGroup differencesCognitionAssociation of Cannabis Use During Adolescence With Neurodevelopment
Albaugh MD, Ottino-Gonzalez J, Sidwell A, Lepage C, Juliano A, Owens MM, Chaarani B, Spechler P, Fontaine N, Rioux P, Lewis L, Jeon S, Evans A, D’Souza D, Radhakrishnan R, Banaschewski T, Bokde ALW, Quinlan EB, Conrod P, Desrivières S, Flor H, Grigis A, Gowland P, Heinz A, Ittermann B, Martinot JL, Martinot M, Nees F, Orfanos D, Paus T, Poustka L, Millenet S, Fröhner JH, Smolka MN, Walter H, Whelan R, Schumann G, Potter A, Garavan H. Association of Cannabis Use During Adolescence With Neurodevelopment. JAMA Psychiatry 2021, 78: 1031-1040. PMID: 34132750, PMCID: PMC8209561, DOI: 10.1001/jamapsychiatry.2021.1258.Peer-Reviewed Original ResearchCannabis useAltered neurodevelopmentAge-related cortical thinningBaseline cortical thicknessAge-related thinningDose-dependent fashionRight prefrontal cortexMR imagesEuropean School Survey ProjectCortical thickness developmentCohort studyCortical thinningStudy baselineCIVET pipelineEndocannabinoid signalingMAIN OUTCOMECortical thicknessAdolescent brain developmentAnimal studiesSignificant associationBrain developmentPrefrontal cortexAdolescent brainBehavioral effectsCortex
2019
Characterizing psychosis-relevant phenomena and cognitive function in a unique population with isolated, chronic and very heavy cannabis exposure
D'Souza DC, Ganesh S, Cortes-Briones J, Campbell MH, Emmanuel MK. Characterizing psychosis-relevant phenomena and cognitive function in a unique population with isolated, chronic and very heavy cannabis exposure. Psychological Medicine 2019, 50: 2452-2459. PMID: 31615592, DOI: 10.1017/s0033291719002721.Peer-Reviewed Original ResearchConceptsSchizotypal Personality QuestionnaireCognitive performanceCannabis exposureTests of attentionComputerized cognitive batteryVisuo-spatial processingHigher SPQ scoresSubstance use/misuseWorse cognitive performanceHeavy cannabis exposureLarge effect sizesUse/misuseCognitive flexibilityVerbal memoryCognitive batteryCognitive functioningPsychomotor speedSPQ scoresCognitive functionCognitive deficitsCannabis usersPersonality QuestionnaireCannabis useUse of cannabisEarly cannabisGrey Matter Volume Differences Associated with Extremely Low Levels of Cannabis Use in Adolescence
Orr C, Spechler P, Cao Z, Albaugh M, Chaarani B, Mackey S, D'Souza D, Allgaier N, Banaschewski T, Bokde ALW, Bromberg U, Büchel C, Quinlan E, Conrod P, Desrivières S, Flor H, Frouin V, Gowland P, Heinz A, Ittermann B, Martinot JL, Martinot MP, Nees F, Orfanos D, Paus T, Poustka L, Millenet S, Fröhner JH, Radhakrishnan R, Smolka MN, Walter H, Whelan R, Schumann G, Potter A, Garavan H. Grey Matter Volume Differences Associated with Extremely Low Levels of Cannabis Use in Adolescence. Journal Of Neuroscience 2019, 39: 1817-1827. PMID: 30643026, PMCID: PMC6407302, DOI: 10.1523/jneurosci.3375-17.2018.Peer-Reviewed Original ResearchConceptsGray matter volumeCannabis useCannabis usersPerceptual Reasoning IndexGreater gray matter volumeMedial temporal lobeBilateral posterior cingulateGeneralized anxiety symptomsBilateral medial temporal lobesInitiation of cannabisRates of cannabisLong-term neurocognitive effectsGray matter volume differencesCognitive effectsHuman adolescentsNeurocognitive effectsAnxiety symptomsVoxel-based morphometryLingual gyrusPosterior cingulateRecreational cannabis useAdolescent periodTemporal regionsHeavy patternNeural maturation
2018
Efficacy and safety of a fatty acid amide hydrolase inhibitor (PF-04457845) in the treatment of cannabis withdrawal and dependence in men: a double-blind, placebo-controlled, parallel group, phase 2a single-site randomised controlled trial
D'Souza DC, Cortes-Briones J, Creatura G, Bluez G, Thurnauer H, Deaso E, Bielen K, Surti T, Radhakrishnan R, Gupta A, Gupta S, Cahill J, Sherif MA, Makriyannis A, Morgan PT, Ranganathan M, Skosnik PD. Efficacy and safety of a fatty acid amide hydrolase inhibitor (PF-04457845) in the treatment of cannabis withdrawal and dependence in men: a double-blind, placebo-controlled, parallel group, phase 2a single-site randomised controlled trial. The Lancet Psychiatry 2018, 6: 35-45. PMID: 30528676, DOI: 10.1016/s2215-0366(18)30427-9.Peer-Reviewed Original ResearchConceptsPF-04457845Cannabis withdrawal symptomsFatty acid amide hydrolaseCannabis withdrawalPlacebo groupAdverse eventsCannabis useWithdrawal symptomsFatty acid amide hydrolase inhibitorSerious adverse eventsPhase 2a trialWeeks of treatmentTreatment of cannabisCannabis use disorderSelf-reported cannabis useDSM-IV criteriaTreatment-related differencesTHC-COOH concentrationsAnandamide concentrationsTreat populationPrimary endpointPill countHospital admissionNovel FAAH inhibitorsSelf-reported cannabisThe Association Between Cannabinoids and Psychosis
Tikka S, D’Souza D. The Association Between Cannabinoids and Psychosis. 2018, 127-155. DOI: 10.1007/978-3-319-90365-1_14.Peer-Reviewed Original ResearchChronic psychotic disordersPsychotic disordersClinical interventionsPsychosis outcomesEmergency department visitsOnset of psychosisPotent synthetic cannabinoidCannabinoid receptor agonistsSignificant clinical interventionHigh rateDuration of intoxicationCannabinoid exposureDepartment visitsCumulative doseReceptor agonistCannabinoid hypothesisClinical significancePeriod of intoxicationCannabinoid productsCannabis useEarly onsetPsychosisPotency of cannabisCannabinoidsRecreational cannabisThe Psychiatric Consequences of Cannabinoids
De Aquino JP, Sherif M, Radhakrishnan R, Cahill JD, Ranganathan M, D'Souza D. The Psychiatric Consequences of Cannabinoids. Clinical Therapeutics 2018, 40: 1448-1456. PMID: 29678279, DOI: 10.1016/j.clinthera.2018.03.013.Peer-Reviewed Original ResearchConceptsPsychiatric effectsPsychiatric disordersPre-existing psychiatric disordersCannabis useLong-term brain changesRates of cannabisNegative psychiatric outcomesNegative psychiatric effectsDose-dependent effectPublic mental healthCannabinoid exposureWithdrawal syndromeCannabis exposureAcute effectsBrain changesMood disordersPsychiatric outcomesGeneral populationPsychomotor functionHealthy individualsMedical cannabisPsychiatric consequencesChronic exposureSignificant impairmentMental healthCannabinoid receptor-mediated disruption of sensory gating and neural oscillations: A translational study in rats and humans
Skosnik PD, Hajós M, Cortes-Briones JA, Edwards CR, Pittman BP, Hoffmann WE, Sewell AR, D'Souza DC, Ranganathan M. Cannabinoid receptor-mediated disruption of sensory gating and neural oscillations: A translational study in rats and humans. Neuropharmacology 2018, 135: 412-423. PMID: 29604295, PMCID: PMC6091633, DOI: 10.1016/j.neuropharm.2018.03.036.Peer-Reviewed Original ResearchConceptsLocal field potentialsSensory gatingCP 55940AM 251Dual-click paradigmNeural oscillationsCannabinoid receptor 1P50 gating ratioGating ratioCannabinoid administrationCB1R agonistEndocannabinoid systemOutcome measuresTranslational studiesReceptor 1Brain regionsAnimal dataCannabis useRatsCannabidiolPlaceboTHC conditionsField potentialsTest dayHuman subjects
2017
Opposing Effects of Cannabis Use on Electroencephalographic Measures of Auditory Repetition Suppression in Schizophrenia and Healthy Controls
Skosnik PD, D’Souza D. Opposing Effects of Cannabis Use on Electroencephalographic Measures of Auditory Repetition Suppression in Schizophrenia and Healthy Controls. Biological Psychiatry Cognitive Neuroscience And Neuroimaging 2017, 2: 209-211. PMID: 29528290, DOI: 10.1016/j.bpsc.2017.03.004.Peer-Reviewed Original Research
2014
Gone to Pot – A Review of the Association between Cannabis and Psychosis
Radhakrishnan R, Wilkinson ST, D’Souza D. Gone to Pot – A Review of the Association between Cannabis and Psychosis. Frontiers In Psychiatry 2014, 5: 54. PMID: 24904437, PMCID: PMC4033190, DOI: 10.3389/fpsyt.2014.00054.BooksPsychotic disordersFamily historyEmergence of psychosisPolymorphisms of COMTPublic health policySymptoms of schizophreniaTrigger relapsePsychosis outcomesHigh riskEpidemiological studiesAcute exposurePsychotomimetic symptomsPsychophysiological abnormalitiesPersistent effectsCognitive deficitsCannabis useHealth policyCannabinoidsSymptomsGenetic factorsCannabisChildhood traumaDisordersStandard criteriaWarrants serious considerationImpact of Cannabis Use on the Development of Psychotic Disorders
Wilkinson ST, Radhakrishnan R, D’Souza D. Impact of Cannabis Use on the Development of Psychotic Disorders. Current Addiction Reports 2014, 1: 115-128. PMID: 25767748, PMCID: PMC4352721, DOI: 10.1007/s40429-014-0018-7.BooksAcute psychosisPsychotic disordersCannabis useAcute intoxicationPersistent psychotic disordersLater psychotic disorderPersistence of psychosisPersistent psychosisHealthy volunteersCognitive symptomsCannabis intoxicationCannabinoid usePsychosisVulnerable populationsComponent causesCannabisIntoxicationGenetic vulnerabilityDose responseSynthetic cannabinoidsChildhood abuseDisordersCannabinoidsPotential riskMore research
2012
Acute effects of THC on time perception in frequent and infrequent cannabis users
Sewell RA, Schnakenberg A, Elander J, Radhakrishnan R, Williams A, Skosnik PD, Pittman B, Ranganathan M, D’Souza D. Acute effects of THC on time perception in frequent and infrequent cannabis users. Psychopharmacology 2012, 226: 401-413. PMID: 23179965, PMCID: PMC3581701, DOI: 10.1007/s00213-012-2915-6.Peer-Reviewed Original ResearchConceptsCannabis smokersAcute effectsFrequent cannabis smokersPlacebo-controlled studyCannabis usersChronic cannabis smokersInfrequent cannabis usersWhole-plant cannabisChronic cannabis useResultsAll dosesVariable pharmacokineticsBlunted responseSubjects three timesHigh dosesTHC effectsFrequent cannabis usersCannabis useInternal clock speedΔ9-tetrahydrocannabinolSmall sample sizeDosesFrequent cannabisThree timesTest daySmokers
2009
Cannabis and psychosis/schizophrenia: human studies
D’Souza D, Sewell RA, Ranganathan M. Cannabis and psychosis/schizophrenia: human studies. European Archives Of Psychiatry And Clinical Neuroscience 2009, 259: 413-431. PMID: 19609589, PMCID: PMC2864503, DOI: 10.1007/s00406-009-0024-2.Peer-Reviewed Original ResearchConceptsPsychotic disordersRole of cannabinoidsPsychosis/schizophreniaTransient psychotic symptomsComponent causesCannabinoid receptor functionCauses of schizophreniaWarrants further studyDuration of exposureCannabinoid exposureTrigger relapsePsychotic illnessPsychotic symptomsGeneral populationCognitive symptomsHealthy individualsHuman studiesReceptor functionCannabis useNeurodevelopmental processesCannabinoidsFirst exposureSymptomsDisordersGenetic factorsCannabinoids and psychosis
Sewell RA, Ranganathan M, D'Souza DC. Cannabinoids and psychosis. International Review Of Psychiatry 2009, 21: 152-162. PMID: 19367509, DOI: 10.1080/09540260902782802.Peer-Reviewed Original ResearchConceptsGeneral populationPsychotic disordersTrigger relapseCannabis usersCognitive symptomsCross-sectional studyIndividual vulnerabilityCannabis useCannabinoid receptor functionLongitudinal studyCase seriesPsychotic illnessPsychotic symptomsCannabisHealthy individualsSchizophreniaPharmacological studiesReceptor functionAutobiographical accountsPsychosisEarly exposureSymptomsTwo-fold increaseConsiderable evidenceComponent causes
2008
Blunted Psychotomimetic and Amnestic Effects of Δ-9-Tetrahydrocannabinol in Frequent Users of Cannabis
D'Souza DC, Ranganathan M, Braley G, Gueorguieva R, Zimolo Z, Cooper T, Perry E, Krystal J. Blunted Psychotomimetic and Amnestic Effects of Δ-9-Tetrahydrocannabinol in Frequent Users of Cannabis. Neuropsychopharmacology 2008, 33: 2505-2516. PMID: 18185500, PMCID: PMC3799954, DOI: 10.1038/sj.npp.1301643.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAmnesiaAttentionBrainDose-Response Relationship, DrugDouble-Blind MethodDronabinolDrug Administration ScheduleDrug ToleranceFemaleHallucinationsHallucinogensHumansHydrocortisoneMaleMarijuana AbuseMiddle AgedPerceptual DisordersProlactinPsychoses, Substance-InducedTachycardiaYoung AdultConceptsAmnestic effectsPerceptual alterationsDelta-9-TetrahydrocannabinolCannabis useSubjective effectsFrequent usersCannabisEffects of cannabinoidsIllicit substancesPsychotomimetic effectsEuphoric effectsHealthy controlsHealthy individualsMemoryImpairingPsychosisDose-related effectsIndividualsCortisolPsychotomimeticsAttentionPeopleUsersPlacebo-controlled studyEffect