Table 1.

Summary of primary findings from human studies reporting neurocognitive effects of regular cannabis use in adolescents and emerging adults (organized by cognitive, structural or functional consequences and clustered according to functional category) (Adapted and modified from Lisdahl et al., 2013).

Cited Cannabis Studies	Neuropsychology Findings	Brain Structure Findings	Blood Flow/ Neurochemistry Findings	Brain Function Findings
Takagi et al., 2011	No difference
*Meier et al., 2012	IQ
*Pope et al., 2003	IQ
*Huestegge et al., 2002	visual search
*Fontes et al., 2011	executive functioning
Grant et al., 2012	executive functioning
*Gruber et al., 2012	executive functioning
Gonzales et al., 2012	executive functioning
Schuster et al., 2012	executive functioning; risky sexual behavior
*Solowij et al., 2012	executive functioning
*Tamm et al., 2013	decision making Early onset MJ: executive functioning in sample with and without ADHD
*Ehrenreich et al., 1999	attention
Fried et al., 2005	processing speed verbal memory
Hanson et al., 2010b	complex attention, verbal memory
Harvey et al., 2007	complex attention, verbal memory; executive functioning
Lisdahl & Price, 2012	complex attention processing speed, sequencing ability, cognitive inhibition
Mathias et al., 2011	complex attention, executive functioning
Medina et al., 2007a	complex attention processing speed, verbal memory, sequencing ability
Tapert et al., 2002	complex attention
McCale & Hunt, 2008	verbal memory, executive functioning
Schwartz et al., 1989	verbal memory
Solowij et al., 2011	verbal memory; executive functioning
Tait et al., 2011	verbal memory
Thoma et al., 2011	verbal memory
Bidwell et al., 2013	trait impulsivity in CNR1 C carriers in CB users
Haughey et al., 2008	withdrawal, negative affect, craving with cues CNR1 C carriers withdrawal, negative +affect, craving with cues FAAH C carriers
*Wilson et al., 2000		total GM; total WM
*Churchwell et al., 2010	executive functioning	right medial OFC
*Lopez-Larson et al., 2011		right caudal, PFC, insula; lingual, temporal, inferior parietal, paracentral thickness
Medina et al., 2009	executive functioning	Females: inferior PFC volume
Ashtari et al., 2011	verbal memory	HC volume
Demirakca et al., 2011		HC volume with THC HC GM with CBD
Jarvis et al., 2008		AMYG volume
Medina, et al., 2007b		left HC volume
McQueeny et al., 2011	depressive symptoms	Females: left AMYG
Schacht et al., 2012		HC, AMYG volumes HC in CNR1 G allele
Churchwell et al., 2012	Novelty Seeking in MJ+ methamphetamine users	left putamen volume
Medina et al., 2010	executive functioning	inferior cerebellar vermis volume
Cousijn et al., 2012		GM volume in cerebellum; no WM differences
DeLisi et al., 2006		No WM differences detected
Arnone et al., 2008		WM integrity (CC)
Ashtari et al., 2009		WM integrity (arcuate fasciculus)
Bava et al., 2009		white matter integrity in 10 regions (PFC, parietal cortex); WM integrity in occipital cortex
Bava et al., 2013		WM FA in R PFC, thalmic fibers, plenium, and posterior corona; MD, RD, and AD in 7 regions
*Gruber et al., 2011	impulsivity	WM integrity in PFC
*Gruber et al., 2013	impulsivity	FA in L & R genu of CC, L internal capsule, mean diffusivity in CC
Medina et al., 2007b	depressive symptoms	global WM in MJ users with depressive sx
Jacobus et al., 2012			blood flow in temporal, insular and PFC regions
Prescot et al., 2011			ACC glutamate, N-acetyl aspartate, creatine, myo- inositol
Silveri et al., 2011			subcortical GM myo- inositol/creatine; WM myo-inositol
Abdullaev et al., 2010				PFC BOLD during attentional control task
*Becker et al., 2010a				left superior PFC BOLD during working memory task in early onset
Becker et al., 2010b				left parahippocampal BOLD during learning task
Behan et al., 2013				connectivity in frontal- parietal-cerebellar network in Go/No-Go task; connectivity in parietal and cerebellar in RS fMRI
Clark et al., 2012				PFC and parietal WM FA
Cousijn et al., 2012	problem severity			DLPFC and ACC in heavy users
De Bellis et al., 2013				L superior lobule, lateral occipital cortex, L & R precuneus in risky decision making task
Feldstein Ewing et al., 2013				insula, parahippocampal, caudate, ACC, and IFG in response to change talk, predicting treatment outcomes
Filbey et al., 2009				PFC, ACC, nucleus accumbens in FAAH C carriers
*Gruber et al., 2012				ACC fMRI BOLD during inhibition task in early onset
Harding et al., 2012				PFC and occipitoparietal connectivity as task demands increase
Houck et al., 2013				PFC activation in RS fMRI
Jacobsen et al., 2007				PFC, parietal connectivity during verbal working memory task
Jacobus et al., 2012				CBF in temporal lobe, insula, and PFC
*Jager et al., 2010				PFC BOLD during working memory task
Lopez-Larson et al., 2012				ACC, cerebellar BOLD during finger tapping
Migliorini et al., 2013				bilateral posterior insula, R PFC, anterior insula to interoceptive stimulation
Schweinsburg et al., 2008				PFC, occipital, parietal BOLD during SWM task
Schweinsburg et al., 2010b				PFC, insula, precentral BOLD during SWM task in recent MJ users
Smith et al., 2010				inferior, middle PFC BOLD during SWM task
Tapert et al., 2007				PFC, parietal, occipital BOLD during inhibitory task
Orr et al., 2013				right low-frequency and frontal-cerebellar interhemispheric connectivity in RS fMRI
Vaidya et al., 2012				ventral medial PFC, cerebellar PET rCBF during IGT task

Notes:

^*= analysis revealed that teenage cannabis use age of onset (<16, 17 or 18 years of age) was associated with significantly poorer neurocognitive outcomes. GM= gray matter; WM= white matter; THC= delta9-tetrahydrocannabinol; CBD= cannabidiol; PFC= prefrontal cortex; IFG= inferior frontal gyrus; ACC= anterior cingulate cortex; HC= hippocampus; AMYG= amygdala; OFC= orbitofrontal cortex; CC=corpus callosum; CBF= cerebral blood flow; PET= positron emission tomography; RS= resting state; SWM= spatial working memory; VWM= verbal working memory; IGT= Iowa Gambling task.