2022
Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis
D’Souza D, DiForti M, Ganesh S, George TP, Hall W, Hjorthøj C, Howes O, Keshavan M, Murray RM, Nguyen TB, Pearlson GD, Ranganathan M, Selloni A, Solowij N, Spinazzola E. Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis. The World Journal Of Biological Psychiatry 2022, 23: 719-742. PMID: 35315315, DOI: 10.1080/15622975.2022.2038797.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsWFSBP Task ForceRisk of psychosisAge of exposureRates of psychosisRecurrent psychosisTask ForceEndocannabinoid systemPsychosis outcomesConsensus paperHigh riskPsychotic disordersPsychotic statesPsychosisPotency of cannabisCriteria of causalityCannabisCannabinoidsLines of evidenceCannabis lawsRiskExposureDisordersEvidenceConfoundersIllness
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 cannabisEffects of haloperidol on the delta-9-tetrahydrocannabinol response in humans: a responder analysis
Gupta S, De Aquino JP, D’Souza D, Ranganathan M. Effects of haloperidol on the delta-9-tetrahydrocannabinol response in humans: a responder analysis. Psychopharmacology 2019, 236: 2635-2640. PMID: 30919005, PMCID: PMC6697616, DOI: 10.1007/s00213-019-05235-x.Peer-Reviewed Original ResearchConceptsDissociative Symptoms ScalePANSS positive scalePsychotomimetic effectsHuman laboratory studiesRole of dopaminePsychosis-like effectsHaloperidol conditionNegative Syndrome ScalePANSS positive scoreDopaminergic antagonismPositive scalePlacebo conditionResponder analysisSyndrome ScaleSymptom ScaleDouble-blind studyEffects of haloperidolDopaminergic signalingOral haloperidolIndividualsOnly respondersPositive scoreIntravenous administrationHealthy individualsHaloperidol
2018
The 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 ResearchMeSH KeywordsAffectBrainCannabinoidsCannabisCognitionEndocannabinoidsHumansMarijuana AbuseMarijuana UseMemoryPsychomotor PerformancePsychotic DisordersConceptsPsychiatric 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 health
2015
The early identification of psychosis: can lessons be learnt from cardiac stress testing?
Gupta S, Ranganathan M, D’Souza D. The early identification of psychosis: can lessons be learnt from cardiac stress testing? Psychopharmacology 2015, 233: 19-37. PMID: 26566609, PMCID: PMC4703558, DOI: 10.1007/s00213-015-4143-3.Peer-Reviewed Original ResearchMeSH KeywordsEarly DiagnosisExercise TestHumansLearningPsychotic DisordersRisk FactorsSchizophreniaSchizophrenic PsychologyConceptsCardiac stress testingCoronary artery diseaseMyocardial infarctionOutcome measuresPsychotic disordersDetection of CADManagement of schizophreniaStress testingManagement of anginaDiagnosis of schizophreniaStress testArtery diseasePsychotic episodePsychiatric disordersPredictive valueEarly identificationEarly detectionSchizophreniaPsychosisDisordersTarget populationRiskSafe stimuliRange of risksUrgent needMarijuana Legalization: Impact on Physicians and Public Health
Wilkinson ST, Yarnell S, Radhakrishnan R, Ball SA, D'Souza DC. Marijuana Legalization: Impact on Physicians and Public Health. Annual Review Of Medicine 2015, 67: 1-14. PMID: 26515984, PMCID: PMC4900958, DOI: 10.1146/annurev-med-050214-013454.BooksConceptsNausea/vomitingRobust clinical evidenceCertain public health issuesPublic health impactPublic health issuePublic healthHigh rateMarijuana useDependence/addictionLegitimate medical useNeuropathic painOpioid useClinical evidenceMultiple sclerosisPulmonary disordersUnintentional ingestionHealth problemsTherapeutic promiseAcute marijuana intoxicationHealth issuesMarijuana intoxicationRecreational useHealth impactsMarijuana productsCannabinoidsRole of GABA Deficit in Sensitivity to the Psychotomimetic Effects of Amphetamine
Ahn KH, Sewell A, Elander J, Pittman B, Ranganathan M, Gunduz-Bruce H, Krystal J, D'Souza DC. Role of GABA Deficit in Sensitivity to the Psychotomimetic Effects of Amphetamine. Neuropsychopharmacology 2015, 40: 2822-2831. PMID: 25953357, PMCID: PMC4864658, DOI: 10.1038/npp.2015.132.Peer-Reviewed Original ResearchConceptsGABA deficitHealthy subjectsPsychotomimetic effectsIntravenous infusionSchizophrenia patientsPANSS positive symptoms subscaleDouble-blind crossover designStriatal dopamine releasePositive symptom subscaleAdministration of drugsDose of AMPHPartial inverse agonistSubclinical responsePharmacokinetic interactionsSubthreshold doseDopamine releaseBenzodiazepine receptorsSymptom subscalesCrossover designCADSS scoresPositive symptomsAMPHInverse agonistSubjective effectsTest dayThe Psychosis-like Effects of Δ9-Tetrahydrocannabinol Are Associated With Increased Cortical Noise in Healthy Humans
Cortes-Briones JA, Cahill JD, Skosnik PD, Mathalon DH, Williams A, Sewell RA, Roach BJ, Ford JM, Ranganathan M, D’Souza D. The Psychosis-like Effects of Δ9-Tetrahydrocannabinol Are Associated With Increased Cortical Noise in Healthy Humans. Biological Psychiatry 2015, 78: 805-813. PMID: 25913109, PMCID: PMC4627857, DOI: 10.1016/j.biopsych.2015.03.023.Peer-Reviewed Original ResearchConceptsPsychosis-like effectsPsychosis-like symptomsPsychotomimetic effectsNegative-like symptomsActive drug conditionsNeural noiseDose-related effectsDose-related mannerRandom neural activityDose-dependent mannerPrincipal active constituentHealthy humansPsychotic disordersCortical noiseDrug conditionsSymptomsΔ9-tetrahydrocannabinolBaseline periodDisorganization symptomsNeural activityCounterbalanced designTest dayActive constituentsOddball taskTHCGABA Deficits Enhance the Psychotomimetic Effects of Δ9-THC
Radhakrishnan R, Skosnik PD, Cortes-Briones J, Sewell RA, Carbuto M, Schnakenberg A, Cahill J, Bois F, Gunduz-Bruce H, Pittman B, Ranganathan M, D'Souza DC. GABA Deficits Enhance the Psychotomimetic Effects of Δ9-THC. Neuropsychopharmacology 2015, 40: 2047-2056. PMID: 25728472, PMCID: PMC4839528, DOI: 10.1038/npp.2015.58.Peer-Reviewed Original Research
2012
Glycine treatment of the risk syndrome for psychosis: Report of two pilot studies
Woods SW, Walsh BC, Hawkins KA, Miller TJ, Saksa JR, D'Souza DC, Pearlson GD, Javitt DC, McGlashan TH, Krystal JH. Glycine treatment of the risk syndrome for psychosis: Report of two pilot studies. European Neuropsychopharmacology 2012, 23: 931-940. PMID: 23089076, PMCID: PMC4028140, DOI: 10.1016/j.euroneuro.2012.09.008.Peer-Reviewed Original ResearchConceptsPilot studyRisk syndromeSyndrome patientsNegative symptomsShort-term pilot studyEffect sizeAdjunctive antipsychotic medicationOpen-label studyPatients meeting criteriaNMDA receptor functionDurability of effectPsychosis risk symptomsGlycine site agonistsGroup effect sizesWeeks of evaluationAntipsychotic medicationSyndrome subjectsPromising effect sizesTreatment needsLarge effect sizesMeeting criteriaCognitive impairmentReduced symptomsReceptor functionSymptomsFeasibility and pilot efficacy results from the multisite Cognitive Remediation in the Schizophrenia Trials Network (CRSTN) randomized controlled trial.
Keefe RS, Vinogradov S, Medalia A, Buckley PF, Caroff SN, D'Souza DC, Harvey PD, Graham KA, Hamer RM, Marder SM, Miller DD, Olson SJ, Patel JK, Velligan D, Walker TM, Haim AJ, Stroup TS. Feasibility and pilot efficacy results from the multisite Cognitive Remediation in the Schizophrenia Trials Network (CRSTN) randomized controlled trial. The Journal Of Clinical Psychiatry 2012, 73: 1016-22. PMID: 22687548, PMCID: PMC3746329, DOI: 10.4088/jcp.11m07100.Peer-Reviewed Original Research
2010
Clinical significance of neurological soft signs in schizophrenia: Factor analysis of the Neurological Evaluation Scale
Sewell RA, Perry EB, Karper LP, Bell MD, Lysaker P, Goulet JL, Brenner L, Erdos J, d'Souza DC, Seibyl JP, Krystal JH. Clinical significance of neurological soft signs in schizophrenia: Factor analysis of the Neurological Evaluation Scale. Schizophrenia Research 2010, 124: 1-12. PMID: 20855185, DOI: 10.1016/j.schres.2010.08.036.Peer-Reviewed Original ResearchConceptsNeurological Evaluation ScaleAbnormal Involuntary Movement ScaleDigit Symbol Substitution TaskWisconsin Card Sorting TestNeurologic deficitsClinical significanceExtrapyramidal Symptom Rating ScaleMore extrapyramidal symptomsBarnes Akathisia ScaleDetailed clinical assessmentNeurological soft signsSymptom Rating ScaleNegative Syndrome ScaleHigher AIMS scoresEvaluation ScaleNeurological deficitsExtrapyramidal symptomsClinical correlatesDeficit syndrome schizophreniaClinical evaluationClinical assessmentAIMS scoresLower PANSSMovement ScaleSoft signsEfeitos comportamentais, cognitivos e psicofisiológicos dos canabinoides: relevância para a psicose e a esquizofrenia
Sewell RA, Skosnik PD, Garcia-Sosa I, Ranganathan M, D'Souza DC. Efeitos comportamentais, cognitivos e psicofisiológicos dos canabinoides: relevância para a psicose e a esquizofrenia. Brazilian Journal Of Psychiatry 2010, 32: 515-530. PMID: 20512267, DOI: 10.1590/s1516-44462010000500005.Peer-Reviewed Original ResearchMeSH KeywordsCannabinoidsCognition DisordersDisease ProgressionHumansMarijuana AbusePsychotic DisordersRisk FactorsSchizophreniaConceptsPsychotic disordersCannabis exposureComponent causesCannabinoid receptor functionCauses of schizophreniaHeavy cannabis exposurePublic health policyCannabinoid exposureTrigger relapsePsychophysiological deficitsCognitive symptomsReceptor functionSchizophreniaHealth policyCannabinoidsLines of evidenceDisordersFurther studiesCannabisSymptomsPsychosisBiological mechanismsExposureIndividual vulnerabilityCause
2009
Modelling psychosis
Curran HV, D’Souza D, Robbins TW, Fletcher P. Modelling psychosis. Psychopharmacology 2009, 206: 513-514. PMID: 19756521, DOI: 10.1007/s00213-009-1663-8.Peer-Reviewed Original ResearchCannabis 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 ResearchMeSH KeywordsAssociationCannabisCognition DisordersHumansMarijuana AbuseNeurotransmitter AgentsPsychotic DisordersSchizophreniaConceptsPsychotic 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 ResearchMeSH KeywordsAnimalsCannabinoidsCannabisHumansMarijuana AbuseMarijuana SmokingPsychotic DisordersReceptors, CannabinoidRisk FactorsSchizophreniaConceptsGeneral populationPsychotic disordersTrigger relapseCannabis usersCognitive symptomsCross-sectional studyIndividual vulnerabilityCannabis useCannabinoid receptor functionLongitudinal studyCase seriesPsychotic illnessPsychotic symptomsCannabisHealthy individualsSchizophreniaPharmacological studiesReceptor functionAutobiographical accountsPsychosisEarly exposureSymptomsTwo-fold increaseConsiderable evidenceComponent causes
2007
Cannabinoids and Psychosis
D'Souza DC. Cannabinoids and Psychosis. International Review Of Neurobiology 2007, 78: 289-326. PMID: 17349865, DOI: 10.1016/s0074-7742(06)78010-2.Peer-Reviewed Original ResearchConceptsReceptor dysfunctionPsychotic disordersTransient psychotic symptomsRecent epidemiological studiesComponent causesRates of cannabisRates of schizophreniaCauses of schizophreniaWarrants further studyAcute psychosisLung cancerCannabis exposureCannabinoid functionHigh riskPsychotic symptomsEpidemiological studiesPeriod of intoxicationPsychosisAvailable evidenceSchizophreniaCannabinoidsGenetic riskBiological plausibilityFurther studiesDysfunction
2006
Revisiting cycloid psychosis: A case of an acute, transient and recurring psychotic disorder
Srihari VH, Lee TS, Rohrbaugh RM, D'Souza DC. Revisiting cycloid psychosis: A case of an acute, transient and recurring psychotic disorder. Schizophrenia Research 2006, 82: 261-264. PMID: 16442782, DOI: 10.1016/j.schres.2005.11.022.Peer-Reviewed Original ResearchConceptsPsychotic disordersCycloid psychosisTransient psychotic disordersICD-10 categoriesIV-TR criteriaMinimal functional impairmentFavorable prognosisRecurrent psychosisUnknown incidenceDistinct pathophysiologyFunctional impairmentClinical attentionPsychosisDisordersFurther investigationPrognosisPathophysiologyIncidenceCasesImpairment
2005
Delta-9-tetrahydrocannabinol effects in schizophrenia: Implications for cognition, psychosis, and addiction
D’Souza D, Abi-Saab WM, Madonick S, Forselius-Bielen K, Doersch A, Braley G, Gueorguieva R, Cooper TB, Krystal JH. Delta-9-tetrahydrocannabinol effects in schizophrenia: Implications for cognition, psychosis, and addiction. Biological Psychiatry 2005, 57: 594-608. PMID: 15780846, DOI: 10.1016/j.biopsych.2004.12.006.Peer-Reviewed Original ResearchMeSH KeywordsAdultAkathisia, Drug-InducedArousalCognitionDose-Response Relationship, DrugDouble-Blind MethodDronabinolEndocrine SystemFemaleHumansInjections, IntravenousMaleMental RecallMiddle AgedMotor ActivityNeuropsychological TestsPerceptionPsychiatric Status Rating ScalesPsychotic DisordersPsychotropic DrugsSchizophreniaVerbal LearningConceptsSchizophrenia patientsAntipsychotic-treated schizophrenia patientsDelta-9-tetrahydrocannabinol effectsLong-term adverse eventsCognitive deficitsPlacebo-controlled studyDelta-9-THCTransient exacerbationAdverse eventsReceptor dysfunctionEndocrine effectsHealthy subjectsStudy participationPsychotic disordersPlasma prolactinSchizophrenia symptomsPatientsSchizophreniaCognitive effectsPerceptual alterationsDeficitsCannabisSubjectsAkathisiaExacerbation