Technology Enhanced Behavioral Activation for Substance Use
It is often the case that individuals with a substance use disorder no longer experience the same positive feelings from everyday non-substance related activities, and are more also likely to experience negative affect and stress. Our treatment, the Life Enhancement Treatment for Substance Use (LETS ACT), aims to increase engagement in rewarding non-substance using activities. Our recent study demonstrated that LETS ACT increases the likelihood of maintaining abstinence up to 1-year post treatment compared to a control condition. We recently developed a smartphone app for LETS ACT to increase availability to the treatment outside of clinician administered sessions, and are currently evaluating its long term effectiveness (NIH R012DA026424).
Neural Response to Reward and Treatment Response
We are also evaluating how individual differences in neural response to reward are associated with treatment factors. Typically, fMRI behavioral tasks examining response to reward use money as a reward, yet we know that it also important for substance users to experience reward when engaging in substance free daily activities. We modified the Monetary Incentive Delay (MID) reward task to capture environmental reward. In our recent study we found that this task, the Behavioral Incentive Delay (BID) task, successfully produced biomarkers of reward processing that are typically seen in tasks that use money as a reward, and was able to distinguished between opiate users and healthy controls.
Neural Correlates of Distress Tolerance
It is known that stress and other forms of negative affect often precede relapse to substance use. We examine individual differences in the ability to persist in goal directed activity when experiencing negative affect, otherwise known as distress tolerance (DT). What we and our colleagues have collectively demonstrated is that individuals with a substance use disorder who can tolerate the stress and negative affect, or who have high DT, are significantly more likely to stay in substance use treatment and maintain successful abstinence. To better understand how neural functioning contributes to DT, we use fMRI to examine neural activity while substance users are engaging in DT tasks. Our most recent finding demonstrates that during stress, substance users with higher DT exhibit stronger connectivity, or co-occurring neural functioning, within areas of their prefrontal cortex, supporting theory that the impairment in the ability of substance users to exert emotion regulation and cognitive control in the face of distress may be a top down neural mechanism. We are now examining how the neural correlates of DT change over time, as well as how functional connectivity within and between neural networks are associated with DT.
The Effect of Non-Invasive Brain Stimulation on Distress Tolerance among Substance Users
Transcranial alternating current stimulation (tACS) is an emerging investigational treatment modality that has the potential to modulate neural oscillations by targeting a specific region of the brain. Substance users demonstrate aberrant oscillatory activity, compared to healthy controls, that are thought to contribute to behavioral and neural deficits in cognitive and affective processes. Led by graduate student Jennifer Yi, we are examining the feasibility of administering tACS in community based substance use treatment settings, as well as the effect of tACS on phenotypes among treatment-seeking substance users. We hope to build upon the findings of this pilot study in order to utilize tACS as a supplementary treatment modality to ideally improve treatment engagement and outcomes.
Distress Tolerance Trajectories among Treatment Seeking Substance Users
Distress tolerance (DT) is not only impaired in substance users but additionally conveys risk of relapse to use, leading to the development of DT-targeted interventions for substance use. However, there is currently a lack of longitudinal studies testing change in DT over time in relation to substance use. Led by graduate student Elizabeth Reese, we are currently investigating changes in distress tolerance over a 1-year period among substance users entering treatment, and in particular the effect of abstinence on these trajectories.
The Role of Affect Dynamics in Substance Use
Early abstinence is a period of heightened emotional vulnerability for individuals with a substance use disorder, making it very likely that they will relapse. Indeed, an estimated 40% to 60% of individuals treated for substances use disorder relapse within one year following treatment. Postdoctoral Associate Dr. Deepika Anand is aiming to specify the role of emotional dysregulation during early abstinence in increasing risk for post-treatment relapse. To do this, she is focusing on the temporal characteristics of affect (e.g. variability, latency) as well as the dynamic relationship between different types of affect (e.g. emotion network density, emotion differentiation). The goal of these analyses is to use individual differences in emotional functioning to identify and specially target individuals at greater risk for relapse.
Cross Cultural Structural and Item Level Differences in Behavioral Activation (BA) Measures
It has been well established by the literature that the same behavior may carry different meanings across culture. Yun Chen is interested in learning whether the items in two behavioral activation measures, the Behavioral Activation for Depression Scale (Kanter et al., 2007) and the Reward Probability Index (Carvalho et al., 2011), are interpreted differently by individuals from Chinese and U.S. culture. Over 900 college participants were recruited from China, Taiwan, and the United States. Differential item functioning tests based on item response theory and factorial invariance models were conducted to understand this cultural different. Findings so far indicated cultural differences in understanding concepts associated with avoidance behaviors (e.g. rumination) and the difference in functioning of C-BADS in China and Taiwan. The psychometric property of C-RPI is currently being investigated.
Translating LETS ACT into Chinese Language
With the goal of introducing BA into Chinese and Taiwanese populations, Yun Chen is currently working with undergraduate students fluent in both Chinese and English to translate LETS ACT into Chinese. The translated manual will be tested among Chinese international students at UNC-CH to gather preliminary information regarding the efficacy of C-BA treatment.