Opioid Addiction
A majority of our research is focused on opioid use disorder (OUD). In 2020, in the midst of the coronavirus pandemic, more than 93,000 people died from drug overdoses, a staggering number that is 30% higher than 2019 (National Center for Health Statistics). The opioid epidemic, in particular, continues to pervade and ravage the United States, accounting for approximately 68% of all drug overdose-related deaths. Although there are effective medications for OUD, adherence to treatment remains poor resulting in frequent relapse to drug use. An even more basic challenge is that many people with OUD and other forms of addiction do not seek out treatment in the first place, in part driven by low perceptions of need or a lack of faith in their ability to achieve sobriety.
In our research, we seek to understand the psychological and brain processes that may prevent people with OUD from seeking and engaging with drug treatment, when doing so could save their life and promote recovery. We use noninvasive brain imaging, especially functional MRI, to visualize the actively thinking brain while people are self-reflecting on their addiction and other kinds of behavior. We also use functional imaging and other biological assays to study basic stress mechanisms in OUD. Stress, which is a known trigger for drug use, is likely to thwart effective self-reflection and related attempts to exert self-control. We hope that a better understanding of the brain and behavior in these contexts will improve treatment outcomes among individuals with OUD and other drug addictions.
Insight
In common language, insight refers to the “aha” moment when something unclear suddenly becomes apparent. In Psychiatry, insight refers to gaining and maintaining self-awareness that one has a mental illness that reduces functioning and requires treatment. It is a concept frequently associated with psychosis and dementia, but more recently has been studied in the context of drug addiction. We study insight in OUD using newly developed functional MRI and behavioral tasks, with special emphasis on brain networks that are involved in self-reflection and self-awareness. Studying and understanding abnormalities in these brain networks can help with the development of new treatments that target affected brain circuits to improve insight in drug addiction.
Metacognition
In common language, metacognition refers to “thinking about thinking.” In the scientific literature, metacognition refers to the ability to monitor one’s own thinking and behavior. Thus, metacognition is related to insight, but it is a broader concept that spans multiple domains beyond one’s addiction. We use functional MRI to understand metacognition in OUD, defined as the correspondence between task accuracy and task confidence. For example, people are said to have higher metacognition when they are highly confident in their performance when they give correct answers and when they are highly unconfident in their performance when they give incorrect answers. We study the brain circuits that underlie these metacognitive processes, as well as their relationships to opioid use and severity.
Stress
Stress is a prominent trigger of drug use. We seek to improve our understanding of biological stress systems in OUD using functional MRI in combination with exposure to drug-related and stressful images. Alongside brain imaging, we obtain laboratory measurements of cortisol and alpha amylase during laboratory stress challenges, and we link these stress markers to drug craving and functional imaging measures.
Smoking Addiction
We also have an ongoing project with cigarette smoking. Although there are effective treatments for smoking cessation, these treatments do not work for everyone. For people who continue to smoke, we need to develop new therapies that address the limitations of existing ones and expand the menu of options. We are therefore studying a neurotransmitter called acetylcholine, which is the main target for nicotine in the brain. To do this, we use positron emission tomography (PET), in combination with a targeted contrast agent, to visualize acetylcholine transmission in the brain. We seek to identify changes in the brain cholinergic system among smokers that can be translated into new clinical therapies.