By Tirthankar Sinha, Ph.D., April 14, 2021
Our theme for April is “Alcohol Awareness Month”. Substance use disorders are a significant public health problem and are extremely difficult to treat. Furthermore, the variability in symptoms and outcomes of these complex conditions make it exceedingly difficult to apply the same treatment option to multiple patients. Thus, tailored treatment, like precision medicine and therapy is the need of the hour. Studying individual differences in neurobehavioral biomarkers can help identify mechanisms of treatment to both improve current treatments and to improve patient-specific-precision-treatment. Two very talented postdocs, Dr. Heather E. Webber and Dr. Constanza Inez C. de Dios, who have been working at the very core of this research area for more than two years at UTHealth, are our Featured Postdocs for April.
Both Dr. Webber and Dr. de Dios are working at the Center for Neurobehavioral Research on Addiction (CNRA), Department of Psychiatry and Behavioral Sciences, UTHealth, and are involved in multiple projects, sometimes even working in close collaboration with each other on the same project.
A widespread problem with people suffering from addiction is that they have a tough time explaining, understanding, and reporting their symptoms. This can result in delaying the assistance that can be provided. So, rather than relying on self-reported symptoms, Dr. Webber analyzes signals from their brain activity to better understand if there are any drug-induced effects. In her own words, “Individuals who have used substances for a long time have a hard time feeling pleasure in response to everyday pleasant things (such as eating delicious food or having a romantic relationship). We can measure how sensitive the brain is to these types of rewards compared to drug-related rewards, rather than asking the participant how much pleasure they would feel if they did those activities”. Further, the brain signals, called “EEG responses” are measured from various patients and then using appropriate statistical tools, it can be predicted which type of treatment would be ideal for the patient. Subsequently, the behavior of the patient is assessed upon showing them images of various drugs, alcohol or of pleasurable elements. This helps gauge if increased use of alcohol or drugs results in a differential response from a separate set of images. These responses are further analyzed statistically to determine the treatment to be provided and the subsequent progress of the patient. Upon her hiring in 2018, UTHealth supported her research for the first few years and generated some preliminary data from these projects. In Feb 2020, Dr. Webber was awarded the prestigious F32 research grant (2 years) from the National Institute on Drug Abuse (NIDA). Using this grant funding, she recently published an article in Experimental and Clinical Psychopharmacology, which looked at individual differences in brain responses of cocaine users. She also recently published a massive review article that took her many years and hours of work in Neuroscience and Biobehavioral Reviews. Another of her work looked at the effects of dextroamphetamine on effort and reward learning, which recently led to a commentary in Neuropsychopharmacology.
Addressing the problem of alcohol and drug abuse from another spectrum, Dr. de Dios employs data science by utilizing Bayesian techniques to answer various questions. She uses statistics to learn why and how some people are more prone to addiction to certain substances (like alcohol or cocaine), and how this might help or hinder them when they are given drug treatments or 'talk' therapy. These analyses are run on large datasets comprising of various levels, from personality and baseline drug use to brain responses and eye movements to pictures, or even their social milieu. Further, as part of the CNRA, her research helps address a wide range of questions with regards to substances such as alcohol, cocaine, and opioids which are of increasing public health concern. She applies statistical learning techniques to the clinical research of substance use disorders (SUDs) and their treatment. A combination of pharmaco- and psychotherapies are administered by the team, and Dr. de Dios’s role as a statistician is to identify what factors might differentiate those most likely to respond well to these therapies from those who do not, among treatment-seeking individuals. This will help the field leverage newer techniques from the realms of data science and biostatistics to answer questions about these substances and apply them to other substances or even behavioral addictions that are a significant burden on public health. She also closely works with various other groups and in a myriad of interesting projects, like using diabetes drugs to help quit smoking, assessing the effects of weight gain on quitting smoking, determining if alcohol abuse can be reduced by adding certain weighted measures, and in collaboration with the Trauma Center at Memorial Hermann, using opioid drugs to minimize pain using fixed doses or minimizing the dose in a patient specific manner. Dr. de Dios is frequently published and one of her recent publication in Journal of Psychopharmacology is titled “Speed-accuracy trade-off during anti-saccade testing differentiates patients with cocaine use disorder who achieve initial treatment abstinence.”
Describing their time at UTHealth, Dr. Webber says that conducting research at UTHealth has greatly contributed to her growth as a researcher – primarily because of the resources it has and the amazing faculty that she has interacted with. She also says, “My favorite thing about UTHealth is the diversity in training and backgrounds within my department and clinic. I have gotten the chance to collaborate with physicians, clinical psychologists, neuroscientists, counselors, and nurse practitioners. Without this diversity in training, it would be impossible to do the kind of research I want to do”. Dr. de Dios is also similarly appreciative about the support she got at UTHealth. She says, “My doctoral degree is in cognitive neuroscience (i.e. basic research in undergraduate populations), so everything I needed to learn about specifically the clinical perspective and the newest advances in statistical learning was new to me, and I had to pick up all of this during my postdoc from the amazing group of advisors who team-mentor me. From my cognitive neuro bubble, I learned to collaborate with people of diverse research backgrounds and interests, and importantly how to communicate the work I do with statistics to my collaborators effectively”. They both agree on what they love most about UTHealth -- “the fact that it is just a thing to be introduced to, or be in contact with, people from very different parts of TMC and the community of Houston as a whole. It's just part of UTHealth culture and that in itself feels very collegial and welcoming. And it goes without saying that the Office of Postdoctoral Affairs has been instrumental in making sure postdocs like me feel welcome and supported”.