Reward-system effect (BAS rating), left hemispheric "unbalance" (alpha band oscillations) and decisional impairments in drug addiction.

The current research explored the impact of cortical frontal asymmetry (left-lateralization effect) and Behavioral Activation System (BAS) on Substance Use Disorder (SUD) in decisional processes using the Iowa Gambling Task (IGT). Forty SUD participants and forty-two controls (CG) were tested using the IGT. Behavioral responses (gain/loss options), BIS/BAS scores and lateralized alpha band modulation (LTA) were considered. The SUD group increased the tendency to opt in favor of the immediate reward (loss strategy) more than the long-term option (win strategy) compared to the CG. Secondly, higher reward-subscale scores were observed in SUD. Thirdly, SUD showed an increase in left-hemisphere activation in response to losing (with immediate reward) choices in comparison with the CG. An imbalanced left hemispheric effect related to higher BAS trait could explain this "reward bias," because these components were found to explain (through the regression analysis) the main behavioral deficits.

Balconi M ，Finocchiaro R ，Canavesio Y 《-》

Left Hemispheric Imbalance and Reward Mechanisms Affect Gambling Behavior: The Contribution of the Metacognition and Cortical Brain Oscillations.

The present research used the Iowa Gambling Task to test the effect of the reward-sensitivity Behavioral Activation System-Reward (BAS-Reward) construct on the ability to distinguish between high- and low-risk decisions. To elucidate the individual differences that influence the decisional processes, making the strategies more or less advantageous, we considered the impact of the BAS motivational system and the frontal left and right cortical activity on subjects' decisions. More specifically, the lateralization effect, which is related to the increased activation of the left (BAS-Reward-related) hemisphere, was explored by using frequency band analysis. Specifically, behavioral responses (gain/loss options), metacognition, and delta, theta, alpha, and beta band modulation (asymmetry index) were considered. Thirty subjects were divided into high-BAS and low-BAS groups. In comparison with low-BAS, the high-BAS group showed an increased tendency to opt in favor of the immediate reward (losing strategy) instead of the long-term option (winning strategy), and members of this group were more impaired in metacognitive monitoring of their strategies and showed an increased left hemisphere activation when they responded to losing choices. A "reward bias" effect was hypothesized to act for high BAS, based on a left-hemisphere hyperactivation.

Balconi M ，Finocchiaro R ，Canavesio Y 《CLINICAL EEG AND NEUROSCIENCE》

Decisional impairments in cocaine addiction, reward bias, and cortical oscillation "unbalance".

Balconi M ，Finocchiaro R 《Neuropsychiatric Disease and Treatment》

Reward bias and lateralization in gambling behavior: behavioral activation system and alpha band analysis.

The present research explored the main factors that can influence subjects' choices in the case of decisions. In order to elucidate the individual differences that influence the decisional processes, making their strategies more or less advantageous, we tested the effect of a reward sensitivity in the behavioral activation system (BAS-Reward) constructed on the ability to distinguish between high- and low-risk decisions. Secondly, the lateralization effect, related to increased activation of the left (BAS-related) hemisphere, was explored. Thirty-one subjects were tested using the Iowa Gambling Task, and the BAS-Reward measure was applied to distinguish between high-BAS and low-BAS groups. Behavioral responses (gain/loss options) and alpha-band modulation were considered. It was found that high-BAS group increased their tendency to opt in favor of the immediate reward (loss strategy) rather than the long-term option (win strategy). Secondly, high-BAS subjects showed an increased left-hemisphere activation in response to losing (with immediate reward) choices in comparison with low-BAS subjects. A "reward bias" effect was supposed to explain both the bad strategy and the unbalanced hemispheric activation for high-BAS and more risk-taking subjects.

Balconi M ，Finocchiaro R ，Canavesio Y ，Messina R ... -  《-》

Reward sensitivity, decisional bias, and metacognitive deficits in cocaine drug addiction.

Balconi M ，Finocchiaro R ，Campanella S 《-》