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John Matochik

Publications and source records attributed to John Matochik.

2 recordsLinked to original sources

Cognitive performance and autonomic reactivity in abstinent drug abusers and nonusers.

In this study the authors compared the performance of abstinent drug abusers (n = 21) and nonuser control participants (n = 20) in neurocognitive and emotional functions by use of the Rogers Decision Making Task, Gambling Task, Emotional Stroop, impulsivity continuous performance task (CPT), and vigilance CPT. Skin conductance (SC) and heart rate (HR) monitoring was synchronized with task performance. Groups showed similar performance for vigilance, impulsivity, and emotional interference; however, drug abusers showed stronger SC responses. Drug abusers performed more poorly on the Gambling and Rogers Decision Making Tasks. When making risky decisions, drug abusers showed significantly less increase in SC activity than controls and exhibited lower HRs throughout performance on all tasks. In conclusion, complex tasks involving decision making, sensitivity to consequences, and emotional regulation discriminated between drug abusers and controls.

Adult↗

Prefrontal cortical dysfunction in abstinent cocaine abusers.

The anterior cingulate cortex (ACC) and lateral prefrontal (LPFC) cortex are brain regions important to executive cognitive functions (ECF). We determined ACC and LPFC function in 23-day abstinent cocaine abusers using positron emission tomography (PET H(2)(15)O) during performance of a modified version of the Stroop Task. Cocaine abusers showed less activation than non-drug-using comparison subjects in the left ACC and the right LPFC and greater activation in the right ACC. Average amount of cocaine used per week was negatively correlated with activity in the rostral ACC and right LPFC. Disruption of ECF in substance abusers could interfere with attempts to stop drug use and undermine treatment. Since impairment in ECF may be a common feature of various neuropsychiatric disorders, these findings have applicability beyond the neurobiology of addiction.

Adult↗