Working memory deficits affect risky decision-making in methamphetamine users with attention-deficit/hyperactivity...

Area of Science:

• Neuroscience
• Psychiatry
• Psychology

Background:

• Methamphetamine (MA) use and Attention-Deficit/Hyperactivity Disorder (ADHD) frequently co-occur.
• Both conditions are linked to impaired frontostriatal circuits and risky decision-making.
• The combined impact of MA use and ADHD on decision-making remains unclear.

Purpose of the Study:

• To investigate whether comorbid MA dependence and ADHD exacerbates risky decision-making compared to MA dependence alone or healthy controls.
• To explore the role of working memory deficits in moderating decision-making in individuals with MA use and ADHD.

Main Methods:

• A cohort of 23 participants with MA dependence and ADHD (MA+ADHD+), 25 with MA dependence only (MA+ADHD-), and 22 healthy controls (MA-ADHD-) were recruited.
• Participants completed the Iowa Gambling Task (IGT) to assess decision-making.
• Neuropsychiatric and cognitive assessments were conducted.

Main Results:

• A significant interaction was found between ADHD, MA use, and working memory capacity.
• Individuals with both MA dependence and ADHD, particularly those with working memory deficits, showed a heightened tendency towards disadvantageous choices on the IGT.
• This effect was independent of other psychiatric, substance use, or cognitive factors.

Conclusions:

• Working memory deficits may significantly moderate the expression of risky decision-making in individuals with comorbid MA use and ADHD.
• Findings suggest specific cognitive vulnerabilities contribute to impaired decision-making in this population.
• This research underscores the complex interplay between substance use, neurodevelopmental disorders, and executive functions in behavioral outcomes.