The Relationship Between Behavioral Inhibition and Approach Motivation Systems (BIS/BAS) and Intrinsic Brain Network Connectivity in Adult Cannabis Users

Functional connectivity changes in males with nicotine addiction: A triple network model study

BACKGROUND

Nicotine addiction (NA) is recognized as a significant neurobehavioral disorder that affects both individuals and society. It is suggested that alterations in functional network connectivity (FNC) within specific brain networks underlie its neurobiological basis.

METHODS

The default mode network (DMN), executive control network (ECN), and salience network (SN) are identified using data from the Human Connectome Project. The study includes 47 individuals with NA and 35 normal controls (NC), all of whom undergo resting-state fMRI alongside smoking-related clinical assessments. A sliding window analysis is employed to assess connectivity metrics, including static functional network connectivity (FNC), standard deviation (SD), and coefficient of variation (CV), to compare information integration between the groups. Participants with NA are classified based on longitudinal changes in Fagerström Test for Nicotine Dependence (FTND) scores over six years into three categories: addiction tendency (AT), withdrawal tendency (WT), and stable tendency (ST). Correlation analyses are conducted to explore relationships between FNC abnormalities and clinical assessments.

RESULTS

Individuals with NA exhibit reduced static FNC (p_FDR = 0.029) between the dorsal DMN and the right ECN, accompanied by increased SD (p_FDR = 0.029) and CV (p_FDR = 0.029). A significant increase in SD (p_FDR = 0.049) is also observed in the dorsal DMN and left ECN. Correlations indicate that the SD of the dorsal DMN and right ECN relates to the pharmacological dimension of the Russell Smoking Reasons Questionnaire (RRSQ) scale (r = 0.416, p_FDR = 0.044), while CV correlates with changes in the FTND over six years (r = -0.391, p_FDR = 0.044) and the pharmacological dimension of the RRSQ scale (r = 0.402, p_FDR = 0.044). Post-hoc subgroup analyses reveal that these FNC intensity changes are present among WT patients (p_FDR < 0.05).

CONCLUSIONS

Alterations in brain network function within the DMN and ECN are suggested to precede behavioral changes in NA. These findings are interpreted as potential neurobiological markers of nicotine addiction.

From individual motivation to substance use initiation: A longitudinal cohort study assessing the associations between reward sensitivity and subsequent risk of substance use initiation among US adolescents

BACKGROUND

Substance use in youth remains a pressing problem in the United States. Existing studies have shown the importance of neuropathways responsible for affective response and reward motivation in adolescents' substance use initiation and maintenance. However, limited observational studies have explored the relationship between aspects of behavioral motivation traits and the likelihood of substance use initiation in adolescents. In this prospective cohort study, we assessed the associations between behavioral motivation traits based on the Behavioral Inhibition and Approach Systems (BIS-BAS) Scale and substance use initiation using data from the Adolescent Brain Cognitive Development (ABCD) study.

METHOD

In the 9216 eligible sample population, we assessed the associations between mean Behavioral Inhibition System (BIS) / Behavioral Approach System (BAS) scores measured at year 2 of the ABCD study and substance use initiation at year 3 of the ABCD study using multivariable logistic regressions adjusting for ABCD study site, sampling weights, as well as sociodemographic characteristics.

RESULTS

We found that higher BIS mean score was associated with higher odds of initiating substance use at year 3 (AOR=1.20, 95 % CI: 1.03, 1.40). Out of three BAS measure categories, only BAS Fun-seeking mean score was positively associated with higher odds of initiating substance use at year 3 (AOR=1.23, 95 % CI: 1.07, 1.43).

CONCLUSION

Our study showed that inhibitory and fun-seeking behavioral tendencies are associated with an increased likelihood of substance use initiation in adolescents. Our findings suggest a potential pathway linking emotional traits to early substance initiation in adolescents.

Resting state functional connectivity in dependent cannabis users: The moderating role of cannabis attitudes

BACKGROUND

The global increase in lenient cannabis policy has been paralleled by reduced harm perception, which has been associated with cannabis use initiation and persistent use. However, it is unclear how cannabis attitudes might affect the brain processes underlying cannabis use.

METHODS

Resting state functional connectivity (RSFC) within and between the executive control network (ECN), salience network (SN), and default mode network (DMN) was assessed in 110 near-daily cannabis users with cannabis use disorder (CUD) and 79 controls from The Netherlands and Texas, USA. Participants completed a questionnaire assessing the perceived benefits and harms of cannabis use from their personal, friends-family's, and country-state's perspectives and reported on their cannabis use (gram/week), CUD severity, and cannabis-related problems.

RESULTS

RSFC within the dorsal SN was lower in cannabis users than controls, while no group differences in between-network RSFC were observed. Furthermore, heavier cannabis use was associated with lower dorsal SN RSFC in the cannabis group. Perceived benefits and harms of cannabis - from personal, friends-family's, and country-state's perspectives - moderated associations of cannabis use, CUD severity, and cannabis use-related problems with within-network RSFC of the SN, ECN, and DMN. Personal perceived benefits and country-state perceived harms moderated the association between CUD severity and RSFC between the ventral and dorsal DMN.

CONCLUSIONS

This study highlights the importance of considering individual differences in the perceived harms and benefits of cannabis use as a factor in the associations between brain functioning and cannabis use, CUD severity, and cannabis use-related problems.