Featured Publications
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 differencesCognitionCompared to high and low cannabis use, moderate use is associated with fewer cognitive deficits in psychosis
Martin A, Bonfils KA, Davis BJ, Smith EA, Schuder K, Lysaker PH. Compared to high and low cannabis use, moderate use is associated with fewer cognitive deficits in psychosis. Schizophrenia Research Cognition 2016, 6: 15-21. PMID: 28740820, PMCID: PMC5514308, DOI: 10.1016/j.scog.2016.09.001.Peer-Reviewed Original ResearchLifetime cannabisCannabis useLess impairmentGroup of patientsDose related responsePoor levelCannabis/Assessment of neurocognitionLifetime cannabis usePoor cognitionSevere impairmentCognitive deficitsCognitive functionLower cannabisModerate cannabisCannabisSchizophreniaImpairmentHigher cannabisNeurocognition
2022
The Relationship Between Cannabinoids and Neural Oscillations: How Cannabis Disrupts Sensation, Perception, and Cognition
Syed S, Martin A, Cortes-Briones J, Skosnik P. The Relationship Between Cannabinoids and Neural Oscillations: How Cannabis Disrupts Sensation, Perception, and Cognition. Clinical EEG And Neuroscience 2022, 54: 359-369. PMID: 36426543, DOI: 10.1177/15500594221138280.Peer-Reviewed Original ResearchConceptsNeural oscillationsNeural synchronyImportant clinical implicationsExcitatory balanceTheta frequency rangeClinical studiesClinical implicationsNeural circuitsCannabis useBrain functionOscillatory disruptionsNeural activityCannabinoidsSensationPotential relationshipCritical mechanismElectroencephalographyDisruptionSchizophreniaThe relationship between cannabis use and taurine: A MRS and metabolomics study
Newman S, Martin A, Raymond D, Cheng H, Wilson L, Barnes S, O’Donnell B. The relationship between cannabis use and taurine: A MRS and metabolomics study. PLOS ONE 2022, 17: e0269280. PMID: 35653401, PMCID: PMC9162360, DOI: 10.1371/journal.pone.0269280.Peer-Reviewed Original ResearchConceptsTaurine levelsCB useBody compositionLow-BMI individualsDorsal anterior cingulateMagnetic resonance spectroscopyNon-user groupNeuroprotective effectsBMI individualsNeurotoxic effectsMRS studiesUrine analysisAnterior cingulateCannabis useSimilar findingsUrine samplesTaurineEssential amino acidsMetabolomic analysisMetabolomics studiesGlutamateCurrent studyGroupBMILevels
2021
Altered cerebellar-cortical resting-state functional connectivity in cannabis users
Martin A, Kim DJ, Newman SD, Cheng H, Hetrick WP, Mackie K, O’Donnell B. Altered cerebellar-cortical resting-state functional connectivity in cannabis users. Journal Of Psychopharmacology 2021, 35: 823-832. PMID: 34034553, PMCID: PMC8813046, DOI: 10.1177/02698811211019291.Peer-Reviewed Original ResearchConceptsResting-state functional connectivityNon-using peersCannabis usersCannabis useFunctional connectivityRegular cannabis usersPosterior cingulate cortexAnterior cerebellar regionsNon-motor phenomenaCingulate cortexCerebellar regionsBrain regionsAge of initiationCerebral regionsCerebellar lobulesCortexPeersLifetime useUnbiased atlas templateIndividual voxelsCerebral cortexReceptor densityCognitionCerebellumAtlas template
2019
Individuals with psychosis and a lifetime history of cannabis use show greater deficits in emotional experience compared to non-using peers
Martin A, Lysaker PH. Individuals with psychosis and a lifetime history of cannabis use show greater deficits in emotional experience compared to non-using peers. Journal Of Mental Health 2019, 29: 77-83. PMID: 30822177, DOI: 10.1080/09638237.2018.1487540.Peer-Reviewed Original ResearchConceptsEmotional Expressivity ScaleEmotional experienceSocial Functioning ScaleEmotional expressionAnticipatory pleasureLifetime cannabisSocial functioningGreater deficitsSocial functionCannabis useNon-using peersAnticipation of pleasureExperience of pleasurePoor social functionEmotional expressivityLifetime historyAnticipatory anhedoniaProsocial activitiesActive cannabisPleasure ScaleTemporal experienceHistory of cannabisFunctioning ScaleEarly psychosisPrevious research
2018
Aberrant structural–functional coupling in adult cannabis users
Kim D, Martin A, Shin Y, Jo HJ, Cheng H, Newman SD, Sporns O, Hetrick WP, Calkins E, O'Donnell BF. Aberrant structural–functional coupling in adult cannabis users. Human Brain Mapping 2018, 40: 252-261. PMID: 30203892, PMCID: PMC6289814, DOI: 10.1002/hbm.24369.Peer-Reviewed Original ResearchConceptsStructural-functional couplingSC-FC couplingResting-state functional imagingCB usersPrimary outcome measureCannabis usersCB1 receptor densityRegion-specific disruptionCB useChronic cannabis useFunctional brain connectivityRich-club organizationOutcome measuresReceptor densitySynaptic plasticityRich-club analysisCannabis useFunctional connectivityBrain connectivityFunctional imagingAdult cannabis usersFunctional couplingBrain networksPositive associationHippocampus
2017
The positive link between executive function and lifetime cannabis use in schizophrenia is not explained by current levels of superior social cognition
Helle S, Løberg EM, Gjestad R, Martin A, Lysaker PH. The positive link between executive function and lifetime cannabis use in schizophrenia is not explained by current levels of superior social cognition. Psychiatry Research 2017, 250: 92-98. PMID: 28152399, DOI: 10.1016/j.psychres.2017.01.047.Peer-Reviewed Original ResearchConceptsSocial cognitionTheory of mindExecutive functionCannabis useBell-Lysaker Emotion Recognition TestEmotion Recognition TestExecutive Functioning ScaleBetter executive functionRegular cannabis useStructural equation modelingHinting testIllicit substancesNeurocognitive vulnerabilityRecognition testNeurocognitive performanceNeurocognitive deficitsCognitionEquation modelingFlexibility componentsAlcohol useFunctioning ScaleLifetime cannabisIndirect effectsPositive linkSchizophrenia
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