Table 2.

Neuroimaging of Decision-Making under Uncertainty in Individuals with Drug Use Disorders

Reference	Imaging Method	Task	Participants	Findings
Bolla et al., 2003	H215O PET	IGT	13 Abstinent cocaine users,10 controls	Cocaine users chose risky options more often and earned less money than controls. Cocaine users had greater activity in the putamen and OFC, but less activity in the dlPFC and medial PFC, compared to controls.
Bolla et al., 2005	H215O PET	IGT	11 Abstinent marijuana users (heavy, moderate use), 11 controls	Abstinent marijuana users had less activation in the lateral OFC and dlPFC compared to controls. Brain activation and task performance of moderate marijuana users was more similar to controls than to heavy marijuana users.
Fein et al., 2006	MRI	IGT	43 Abstinent alcohols, 58 controls	Abstinent alcoholics with impairments on the task had smaller amygdala volume than controls.
Wesley et al., 2011	fMRI	IGT	16 Marijuana users, 16 controls	Marijuana users had weaker responses to losses in the ACC and medial frontal cortex, compared to controls. Marijuana users lacked a correlation between task performance and activity in the ACC, vmPFC, and rostral PFC that was demonstrated in controls.
Cousijn et al., 2012	fMRI	IGT	32 Cannabis users, 41 controls	Marijuana users had greater responses to wins vs. losses in the right OFC, superior temporal gyrus, and insula, compared to controls. Superior temporal gyrus activity correlated with higher marijuana use in the 6 months following testing.
Vaidya et al., 2012	H215O PET	IGT (standard + variant with focus on punishment)	46 Marijuana users, 34 controls	Marijuana users had worse performance than controls on the punishment variant of the IGT. Marijuana users had stronger activation than controls in the vmPFC during the standard IGT. vmPFC activation positively correlated with duration of marijuana use.
Crowley et al., 2010	fMRI	BART	20 Abstinent adolescent males at risk for substance use, 20 controls	Adolescents at risk for substance abuse had lower amygdala, insula, and ACC activation compared to controls.
Kohno et al., 2014	fMRI	BART	25 Methamphetamine users, 27 controls	Compared to controls, methamphetamine users had greater modulation of ventral striatal activation, but less modulation of dlPFC activation, by risk and reward. Methamphetamine users had greater RSFC of midbrain with the putamen, amygdala, and hippocampus, and RSFC was inversely related to dlPFC sensitivity to risk.
Kohno et al., 2016	[18F]fallypride PET and fMRI	BART	19 Methamphetamine users, 26 controls	Negative relationship between ventral striatal binding potential and RSFC of midbrain with striatum, OFC, and insula in methamphetamine users, but positive relationship in controls. Positive relationship between midbrain RSFC to ventral striatum and cognitive impulsivity in methamphetamine users, but negative relationship in controls.
Ersehe et al., 2005	H215O PET	Cambridge Risk Task	15 Chronic amphetamine, 15 chronic opiate, 15 former opiate and amphetamine users, 15 controls	Lower ACC activity was related to greater risk propensity in all drug user groups. Activation was greater in left PFC, but lower in right dlPFC of drug users vs. controls
Ersehe et al., 2006	H215O PET	Cambridge Risk Task	9 Methadone-maintained opiate users, 6 heroin users, 5 controls	Activity in the ACC and insula was related to propensity to avoid risk following loss in controls, but not in opiate users. Compared to controls, opiate users had abnormal patterns of OFC activity that was associated with risk preferences.
Fishbein et al., 2005a	H215O PET	Rogers Decision-Making Task	13 Abstinent drug users, 14 controls	ACC activity was lower in drug users vs. controls. Lower ACC activity was related to greater risk propensity.
Bjork et al., 2008	fMRI	Monetary game of Chicken	17 Alcohol and cocaine users, 17 controls	ACC activity on trials that included risk was greater for controls than for drug users. Posterior mesofrontal cortical activity was lower in drug users vs. controls.
Gowin et al., 2014b	fMRI	Risky Gains Task	68 Methamphetamine users, 40 controls	Methamphetamine users had lower insula activity than controls across all trials. Mid-insula activity was greater during risky vs. safe decisions in methamphetamine users. Methamphetamine users had less ACC activity following losses than controls, and were more likely to make risky decisions following losses.
Reske et al., 2015	fMRI	Risky Gains Task	158 Young adult occasional stimulant and marijuana users, 50 controls	Substance users had less activity in the ACC, PFC, insula, and dorsal striatum than controls, and attenuation in ACC activity was inversely related to past drug use. Less neural differentiation between safe and risky trials was exhibited by drug users and was driven by a lack of deactivation in the right dorsal striatum and PFC areas during safe decisions.

Brain regions: ACC: anterior cingulate cortex; dlPFC: dorsolateral PFC; OFC: orbitofrontal cortex; PPC: posterior parietal cortex; PFC: prefrontal cortex; vmPFC: ventromedial PFC; vlPFC: ventrolateral PFC.

Measures: RSFC: resting-state functional connectivity