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Updated: Jun 10, 2026
06:11
A Conflict Model of Reward-seeking Behavior in Male Rats
Published on: February 20, 2019
A genetically modulated, intrinsic cingulate circuit supports human nicotine addiction
L Elliot Hong1, Colin A Hodgkinson, Yihong Yang
1Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA. ehong@mprc.umaryland.edu
Summary
Genetic variants linked to smoking affect brain circuit connectivity. This specific neural circuit
Area of Science:
- Neuroscience
- Genetics
- Psychiatry
Background:
- Nicotinic acetylcholine receptor (nAChR) gene variants are associated with smoking behavior.
- The neural mechanisms linking these genetic predispositions to smoking addiction are not well understood.
Purpose of the Study:
- To investigate how a specific alpha5 gene variant influences brain circuit function related to smoking.
- To identify neural circuitry biomarkers for smoking addiction.
Main Methods:
- Examined the association between the alpha5 gene variant (Asp398Asn) and resting-state functional connectivity in a specific brain circuit.
- Analyzed circuit strength in smokers, nonsmokers, and individuals with mental illnesses.
Main Results:
- The "risk allele" of the alpha5 gene variant was associated with decreased functional connectivity in the dorsal anterior cingulate-ventral striatum/extended amygdala circuit.
- This circuit's strength was a trait-like biomarker, distinguishing smokers from nonsmokers and predicting addiction severity.
- The circuit was also found to be impaired in individuals with mental illnesses, who exhibit high smoking rates.
Conclusions:
- A specific alpha5 gene variant impacts brain circuit connectivity, offering a potential neural basis for smoking addiction.
- The dorsal anterior cingulate-ventral striatum/extended amygdala circuit serves as a trait-like biomarker for smoking behavior and addiction.
- Identifying these gene-circuitry links provides targets for novel smoking cessation treatments.
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