Dorsolateral prefrontal and orbitofrontal cortex interactions during self-control of cigarette craving

Area of Science:

• Neuroscience
• Addiction Research

Background:

• Drug cues trigger craving, perpetuating use and relapse.
• Frontal lobe activity influences cue reactivity, but specific regions remain unclear.

Purpose of the Study:

• To investigate frontal lobe contributions to drug craving under varying drug availability.
• To determine the role of the dorsolateral prefrontal cortex (DLPFC) in regulating craving based on intertemporal availability.

Main Methods:

• Combined transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) in smokers.
• Transiently inactivated the DLPFC using TMS to assess its causal role.
• Examined brain activity in relation to subjective craving and drug availability.

Main Results:

• Subjective craving increased when cigarettes were immediately available; this effect was abolished by DLPFC inactivation.
• Medial orbitofrontal cortex (mOFC) activity correlated with craving, while DLPFC encoded availability information.
• DLPFC inactivation attenuated mOFC craving signals, particularly when drugs were readily available, and reduced signals in the anterior cingulate and ventral striatum.

Conclusions:

• The DLPFC integrates drug availability information to modulate craving.
• Aberrant connectivity between DLPFC and mOFC may underlie addiction.
• DLPFC plays a key role in linking drug availability to craving and subsequent actions.