<b>EFFECTS OF ABSTINENCE IN EARLY ADDICTION RECOVERY ON FUNCTIONAL BRAIN NETWORKS AND BEHAVIORS</b>
Creators: name: Shen, Yitong
Publisher: name: Purdue University Graduate School
Year: 2024
Subjects: classificationCode: 320999
subject: Neurosciences not elsewhere classified
classificationCode: 520202
subject: Behavioural neuroscience

description: <b>ABSTRACT</b><b>Background</b>Alcohol use disorder (AUD) poses negative health and social consequences, and is costly to affected individuals, loved ones, and society (Whiteford et al., 2013). It is a chronic neuropsychiatric disorder, associated with impaired decision making and altered functional connectivity patterns in the brain. Many studies have shown changes in the brain and behaviors after sustained abstinence using within-participant design or between-participant design comparing participants in recovery versus healthy controls (Muller &amp; Meyerhoff, 2021; Wilcox et al., 2019). The purpose of this study was to investigate brain differences between participants in recovery and participants who are actively drinking. Specifically, this study evaluated within- and between-network resting-state functional connectivity (rsFC) strengths in the context of the triple network model, which focuses on three key networks for complex perceptual, emotional and behavior processing as well as introspection, theory of mind and self-awareness; the salience network (SN), the central executive network (CEN), and the default mode network (DMN) (Menon, 2019). Moreover, this study assessed the relationship between impulsive choices in temporal decision-making and changes in resting-state functional connectivity patterns in these networks.<b>Methods</b>This study included two groups: the Recovery Group and the Drinking Group. The Recovery Group included participants who were starting recovery (within one year), met AUD diagnosis criteria or showed lifetime heavy drinking behaviors during a 12-month period, received treatment for substance use disorder for alcohol and/or illicit drugs, and showed ongoing intentions and efforts to maintain recovery (n=18, 6 females, mean age=32.4±7.4, 17 White, mean years of education=14.5±3.1, average days of abstinence prior to interview days=78.2±45.7). The Drinking Group included participants who were currently drinking that met diagnosis criteria for AUD or showed heavy drinking behaviors (n=49, 24 females, mean age=31.7±6.4, 29 White, mean years of education=13.6±2.3). Participants underwent an initial screen day where structured interviews were conducted to evaluate the number of lifetime AUD criteria and prior drinking patterns. On the study day, participants completed computer tasks and questionnaires prior to their functional Magnetic Resonance Imaging (fMRI) sessions. Participants in the Recovery Group received a virtual reality (VR) intervention targeting future self-continuity where they interacted with avatars that are versions of themselves (present self and future selves in recovery and relapsed) prior to MRI sessions. All participants completed baseline Delay Discounting (DD) to measure intertemporal choice preferences prior to the fMRI sessions and prior to the VR intervention for the Recovery Group.<b>Results</b>This study did not find any significant differences in within- and between-network rsFC strength of regions of interest of this study within the triple networks between participants in recovery and those who were actively drinking. The study found that participants in recovery showed a greater preference for delayed rewards (measured by DD task) compared to participants who are actively drinking. Additionally, measures of self-reported impulsivity and impulsive decision-making were associated with resting state functional connectivity (rsFC) strength between regions within the Salience Network (SN), and between the SN and Central Executive Network (CEN). Specifically, baseline delayed reward preference was positively associated with the rsFC between two SN hubs: left dorsal anterior insula (dAIC) and dorsal anterior cingulate cortex (dACC). The rsFC between the left dACC (SN) and dorsolateral prefrontal cortex (dlPFC; CEN) negatively associated with subscales (including negative urgency, lack of perseverance, and lack of premeditation) of self-reported impulsivity measured by the Urgency-Premeditation-Perseverance-Sensation Seeking-Positive Urgency (UPPS-P) impulsive behavior scale. Together, these results suggested that there was an emerging pattern where enhanced the rsFC strength in these regions associated with higher impulsive tendencies. The exploratory analysis showed that the rsFC strength between the right precuneus and ventromedial prefrontal cortex (vmPFC) was related to abstinence length in participants in recovery.<b>Conclusions</b>These findings indicated that participants in recovery exhibited higher delayed reward preference compared to participants who were actively drinking, alongside a significant relationship between measures of impulsivity and the rsFC within the SN and between the SN and CEN. These results highlighted the importance of the SN and its dynamic interaction with the CEN in self-reported impulsivity and impulsive decision making in addiction. Additionally, this study found that within-network functional connectivity strength in the DMN was related to abstinence length, suggesting that repairment in the rsFC strength within DMN might be integral to the process of addiction recovery.<br>