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Disrupted functional connectivity with dopaminergic midbrain in cocaine abusers
Dardo Tomasi1, Nora D Volkow, Ruiliang Wang
1National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, USA. tomasi@bnl.gov
Plos One
|June 4, 2010
Summary
Chronic cocaine use disrupts brain connectivity, impacting sustained attention. Cocaine abusers show reduced midbrain functional connectivity, affecting attention networks and cognitive control.
Area of Science:
- Neuroscience
- Neuroimaging
- Addiction Research
Background:
- Chronic cocaine use disrupts dopaminergic neurotransmission.
- The impact of this disruption on overall brain function beyond reward pathways remains under-investigated.
Purpose of the Study:
- To investigate disrupted functional connectivity in cocaine-addicted individuals.
- To examine midbrain connectivity with cortical and subcortical regions during sustained attention tasks.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used to measure brain activation and functional connectivity.
- 20 cocaine abusers and 20 matched controls participated in the study.
Main Results:
- Cocaine abusers exhibited lower positive functional connectivity between the midbrain and thalamus, cerebellum, and rostral cingulate compared to controls.
- This reduced connectivity correlated with decreased activation in the thalamus and cerebellum, and enhanced deactivation in the rostral cingulate.
Conclusions:
- Decreased midbrain functional connectivity in cocaine addicts interferes with neural signals for sustained attention.
- Findings highlight the broader cognitive deficits associated with cocaine addiction beyond reward circuitry.
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