Dataset Information

Attenuated Neural Processing of Risk in Young Adults at Risk for Stimulant Dependence.

ABSTRACT:

Objective

Approximately 10% of young adults report non-medical use of stimulants (cocaine, amphetamine, methylphenidate), which puts them at risk for the development of dependence. This fMRI study investigates whether subjects at early stages of stimulant use show altered decision making processing.

Methods

158 occasional stimulants users (OSU) and 50 comparison subjects (CS) performed a "risky gains" decision making task during which they could select safe options (cash in 20 cents) or gamble them for double or nothing in two consecutive gambles (win or lose 40 or 80 cents, "risky decisions"). The primary analysis focused on risky versus safe decisions. Three secondary analyses were conducted: First, a robust regression examined the effect of lifetime exposure to stimulants and marijuana; second, subgroups of OSU with >1000 (n = 42), or <50 lifetime marijuana uses (n = 32), were compared to CS with <50 lifetime uses (n = 46) to examine potential marijuana effects; third, brain activation associated with behavioral adjustment following monetary losses was probed.

Results

There were no behavioral differences between groups. OSU showed attenuated activation across risky and safe decisions in prefrontal cortex, insula, and dorsal striatum, exhibited lower anterior cingulate cortex (ACC) and dorsal striatum activation for risky decisions and greater inferior frontal gyrus activation for safe decisions. Those OSU with relatively more stimulant use showed greater dorsal ACC and posterior insula attenuation. In comparison, greater lifetime marijuana use was associated with less neural differentiation between risky and safe decisions. OSU who chose more safe responses after losses exhibited similarities with CS relative to those preferring risky options.

Discussion

Individuals at risk for the development of stimulant use disorders presented less differentiated neural processing of risky and safe options. Specifically, OSU show attenuated brain response in regions critical for performance monitoring, reward processing and interoceptive awareness. Marijuana had additive effects by diminishing neural risk differentiation.

SUBMITTER: Reske M

PROVIDER: S-EPMC4468216 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Attenuated Neural Processing of Risk in Young Adults at Risk for Stimulant Dependence.

Reske Martina M Stewart Jennifer L JL Flagan Taru M TM Paulus Martin P MP

PloS one 20150615 6

<h4>Objective</h4>Approximately 10% of young adults report non-medical use of stimulants (cocaine, amphetamine, methylphenidate), which puts them at risk for the development of dependence. This fMRI study investigates whether subjects at early stages of stimulant use show altered decision making processing.<h4>Methods</h4>158 occasional stimulants users (OSU) and 50 comparison subjects (CS) performed a "risky gains" decision making task during which they could select safe options (cash in 20 cen ...[more]

PMID: 26076493

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Dataset Information

Attenuated Neural Processing of Risk in Young Adults at Risk for Stimulant Dependence.

Objective

Methods

Results

Discussion

Publications

Attenuated Neural Processing of Risk in Young Adults at Risk for Stimulant Dependence.

Similar Datasets

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