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 cannabis
2017
Tetrahydrocannabinol (THC) impairs encoding but not retrieval of verbal information
Ranganathan M, Radhakrishnan R, Addy PH, Schnakenberg-Martin AM, Williams AH, Carbuto M, Elander J, Pittman B, Sewell R, Skosnik PD, D'Souza DC. Tetrahydrocannabinol (THC) impairs encoding but not retrieval of verbal information. Progress In Neuro-Psychopharmacology And Biological Psychiatry 2017, 79: 176-183. PMID: 28642081, DOI: 10.1016/j.pnpbp.2017.06.019.Peer-Reviewed Original ResearchConceptsRey Auditory Verbal Learning TestVerbal informationInfluence of tetrahydrocannabinolVerbal Learning TestMemory-impairing effectsTotal immediate recallNon-verbal informationImpairs memory consolidationAdministration of tetrahydrocannabinolAcute memory impairmentPrincipal psychoactive constituentVerbal memoryImmediate recallIntravenous tetrahydrocannabinolLearning TestMemory consolidationComponent processesNeural synchronyMemory impairmentInformation processingUse of cannabisCannabis intoxicationRecallPsychoactive constituentEncodingMinimal effects of prolonged smoking abstinence or resumption on cognitive performance challenge the “self-medication” hypothesis in schizophrenia
Boggs DL, Surti TS, Esterlis I, Pittman B, Cosgrove K, Sewell RA, Ranganathan M, D'Souza DC. Minimal effects of prolonged smoking abstinence or resumption on cognitive performance challenge the “self-medication” hypothesis in schizophrenia. Schizophrenia Research 2017, 194: 62-69. PMID: 28392208, PMCID: PMC5630481, DOI: 10.1016/j.schres.2017.03.047.Peer-Reviewed Original ResearchConceptsProcessing speedMultiple cognitive domainsCognitive test performancePro-cognitive effectsSelf-medication hypothesisNicotine-dependent smokersVerbal memoryVerbal recallCognitive batteryCognitive domainsExecutive functionVerbal fluencyBehavioral measuresTest batteryCognitive deficitsTest performanceSmoking cessationSmoking abstinenceNegative symptomsConflict resolutionAbstinenceCognitionDepressive symptomsSchizophreniaSmoke cigarettes