Brain structural substrates of reward dependence during behavioral performance.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuroimaging

Background:

• Individual variability in reward dependence impacts performance.
• The neuroanatomical basis for this reward dependence remains unclear.
• Understanding reward sensitivity is crucial for various applications, including neurorehabilitation.

Purpose of the Study:

• To investigate the relationship between individual differences in reward dependence and brain structure in healthy adults.
• To identify potential anatomical markers associated with varying sensitivity to reward.
• To explore the neural underpinnings of reward's influence on skill acquisition.

Main Methods:

• Participants underwent a visuomotor skill-acquisition task with performance feedback.
• Reward was provided during specific task phases to assess its impact.
• Reward dependence was quantified by the trial-by-trial relationship between reward and performance.
• Structural magnetic resonance imaging (MRI) was used to analyze regional gray-matter volume.
• Multivoxel pattern analysis (MVPA) was employed to confirm anatomical specificity.

Main Results:

• A significant correlation was found between reward dependence and gray-matter volume in the lateral prefrontal cortex.
• The volume of specific lateral prefrontal cortex regions predicted an individual's level of reward dependence.
• This relationship was specific to reward dependence and not observed with feedback alone.
• MVPA corroborated the anatomical specificity of the findings.

Conclusions:

• Regional gray-matter volume in the lateral prefrontal cortex serves as a potential anatomical marker for reward dependence.
• These findings elucidate the neural basis of individual differences in reward sensitivity.
• The identified marker may have implications for understanding and potentially intervening in neurorehabilitative contexts.