Current Fellows
The CCB currently supports post-doctoral Fellows working at most NIH Institutes with neuroscience research. The fellows' research focus span a wide range of topics related to compulsive behaviors, that include synaptic mechanisms driving compulsive drug taking, neural circuitry that mediates relapse, and behavioral paradigms that promote compulsive overeating.

First Year Fellows
Khushbu Agarwal, Ph.D. (NIAAA)

Currently as a postdoctoral visiting fellow in the SenSMet unit, NIAAA at NIH, Dr. Khushbu Agarwal is working with Dr. Joseph’s group to study the link between chemosensation, brain function, and behavior in addictive conditions such as obesity, and alcohol use disorder (AUD). The focus is to understand the reward associated neural mechanisms associated with chemosensory and physiological changes in obesity and AUD individuals. To address the objective of her study a battery of psychophysical, physiological, cognitive, and neuroimaging assessments are conducted. She has been granted the prestigious CCB NIH fellowship in 2022 and her CCB project aims at characterizing the olfactory function of the AUD individuals and determine the functional brain cue reactivity to rewarding odor stimuli and explore if inflammation is associated with the olfactory measures and altered cue reactivity craving and reward responses in AUD population.
She has completed her Ph.D. studies from All India Institute of Medical Sciences (AIIMS), New Delhi, India in the year 2018. During her Ph.D studies she gained extensive experience in molecular biology and multimodal MRI techniques in clinical population like patients with breast cancer and brain disorders including obsessive compulsive and bipolar disorders.
Hector Bravo-Rivera, Ph.D. (NIMH)
Hector is a postdoc at the Unit for Neuromodulation and Synaptic Integration (UNSI) mentored by Dr Hugo Tejeda. His project focuses on the role of mesocortical dopamine in the resolution of approach/avoidance conflict.
He completed his PhD in the University of Puerto Rico School of Medicine in Dr Gregory Quirk’s lab where he focused on behavioral models of approach/avoidance conflict in rodents and non-human primates.
Diana Burk, Ph.D. (NIMH)

Diana is a postdoctoral fellow in the Section on Learning & Decision Making, led by Dr. Bruno Averbeck at the National Institute of Mental Health. Her research investigates the neural representation of primary and secondary rewards and motivation during reinforcement learning. Her CCB project involves combining computational modeling and electrophysiology in awake, behaving non-human primates to measure neural activity during learning.
She received her B.S. in Biomedical Engineering from the University of Virginia in 2011, M.Phil in Neuroscience from the University of Cambridge in 2013, and her Ph.D. in Neuroscience from Brown University in 2020. Her past work has been in various areas of neuroscience, including the neural control of movement, perceptual decision making, and visual object recognition in humans and non-human primates.
In her free time, she enjoys exploring trail systems through running and bike racing.
Tommy Gunawan, Ph.D. (NIAAA)

Dr. Tommy Gunawan is a Visiting Postdoctoral Fellow at the Human Psychopharmacology Laboratory and Office of the Clinical Director under the guidance of Dr. Vijay Ramchandani at NIAAA. He is currently investigating the neurofunctional domains underlying alcohol use disorder. His CCB project will look at the interactions between ALDH2 polymorphism and famotidine on alcohol response, alcohol reward, alcohol motivation, and metabolism in both clinical and preclinical models. His goal is to understand drug-seeking and polydrug use behavior and to develop methods for translating between preclinical and clinical research.
Dr. Tommy Gunawan was born in Indonesia, grew up in Singapore, and completed his undergraduate and graduate studies in the United States. He earned his Ph.D. in Behavior, Cognition, and Neuroscience from American University in 2020. He is interested in the neuropsychopharmacology of addictive drugs. He enjoys nature, hiking, cooking, and chess.
Andras Leko, M.D., Ph.D. (NIDA)

Dr. Leko is a Postdoctoral Visiting Fellow in the Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology (CPN), a joint laboratory of the National Institute on Drug Abuse (NIDA) and National Institute on Alcohol Abuse and Alcoholism (NIAAA) (P.I.: Dr. Lorenzo Leggio). As a 2022 CCB Fellow, he will investigate the Mineralocorticoid Receptor (MR) as a novel pharmacotherapeutic target in Alcohol Use Disorder (AUD) by conducting a Phase 1b human laboratory study with the MR-antagonist spironolactone. The study will examine pharmacokinetic (PK) and pharmacodynamic (PD) parameters of spironolactone and alcohol, during concomitant oral administration, and test the safety and tolerability of spironolactone, co-administered with alcohol, in individuals with AUD.
Dr. Leko received both his M.D. and Ph.D. in Neuroscience from Semmelweis University of Budapest, Hungary. His primary research focused on neural circuits responsible for maternal behavior. He identified insulin-like growth factor-1 (IGF-1) as a novel regulator of prolactin release and maternal motivation. More recently, he has applied transcriptome sequencing approaches to investigate genes responsible for maternal adaptation of the central nervous system and identified a potential role of the androgen receptor in the control of maternal behaviour. Dr. Leko began his residency in Psychiatry in 2017, in the Department of Psychiatry and Psychotherapy at Semmelweis University, Budapest.
Tingting Liu, Ph.D. (NIDA)

Dr. Tingting Liu is currently a postdoctoral researcher in Technology and Translational Research Unit in Translational Addiction Medicine Branch, at NIDA IRP. Her project within the CCB aims to investigate the neural mechanisms and behavioral consequences of alcohol-related stigma among heavy drinkers.
Dr. Tingting Liu received her Ph.D. in psychology from the University of Michigan. She utilizes novel interdisciplinary methodologies from psychology, neuroscience, and computational text analysis to investigate social relationships in mental health and substance use behaviors. She likes travelling and photography.
Zilu Ma, Ph.D. (NIDA)

Zilu is a Post-doctoral Fellow in Dr. Yihong Yang’s lab at the National Institute on Drug Abuse (NIDA). As a first year CCB Fellow, Zilu will study role of dorsal striatum circuits in relapse to opioid seeking by combining functional magnetic resonance imaging (fMRI), pharmacological inactivation, and intermittent theta burst stimulation (iTBS) methods.
Zilu received her Ph.D. degree in Biomedical Engineering from The Pennsylvania State University in 2020. Her Ph.D. concentrated on developing awake resting-state fMRI methods to study brain function by incorporating it with different neuroimaging, behavioral, and neuromodulation methods in animal models.
Aijaz Naik, Ph.D. (NIMH)

As a 2022 CCB Fellow, Aijaz is employing neuron tagging, whole brain imaging, behavior, transgenic and optogenetic strategies in mice to understand the neural circuits and mechanisms of frustration-effect following withholding of expected rewards. Disentangling the neural circuits mediating frustration will shed light on how dysfunction in dedicated circuits may lead to low frustration tolerance and propensity for aggression seen in Children and Teens with Irritability. Neuroscience of irritability is still in infancy, Aijaz aims to generate fresh insights that would aid translational efforts and precise therapeutics for irritability.
Aijaz joined NIH-IRP as a postdoctoral fellow in March 2021. He is currently a Research Fellow in Section on Synapse Development Plasticity in Zheng Li’s group at the National Institute on Mental Health (NIMH).
Aijaz received his Ph.D. from India, where he studied how intragenerational Protein malnutrition affects gliogenesis and cognitive functioning in F1 progeny rats. Aijaz moved to University of Virginia, School of Medicine as a Postdoctoral fellow (2018-2021), where he investigated mechanisms of seizure induced amnesia using activity dependent tagging of memory and seizure engrams, electrophysiology, and mouse behavior.
Outside of the lab, Aijaz loves to cook new recipes and hiking occasionally.
Katherine Savell, Ph.D. (NIDA)

Katherine E. Savell, Ph.D., is a postdoctoral fellow in the laboratory of Dr. Bruce Hope in the Behavioral Neuroscience Research Branch of the National Institute on Drug Abuse Intramural Research Program. Her postdoctoral research focuses on understanding how drug-related associations are encoded and maintained in the brain by leveraging single nuclei RNA-sequencing and neuronal activity-dependent transgenic tools in preclinical relapse models.
Katherine earned a Ph.D. in Genetics, Genomics, and Bioinformatics, with a focus in neuroscience, from the University of Alabama at Birmingham. Outside of the lab, Katherine can be found in her garden or stained glass studio with a cat by her side.
Rachel Walker, Ph.D. (NIMH)

Rachel is a Postdoctoral Fellow working with Dr. Mario Penzo in the Unit on the Neurobiology of Affective Memory at the National Institute of Mental Health (NIMH). Broadly, her interests are in understanding the neural mechanisms behind fear memories and related defensive behaviors. As a CCB fellow, Rachel aims to uncover the neural circuitry underlying excessive avoidance behavior using whole brain imaging, optogenetics, and calcium imaging.
Rachel earned her Ph.D. in Behavioral Neuroscience from Boston College under the mentorship of Dr. Michael McDannald. During her Ph.D., Rachel investigated the neural basis of aversive prediction error signaling and the long-term impacts of early life stress.
Second Year Fellows
Yosuke Arima, Ph.D. (NIDA)
Yosuke is a postdoctoral fellow in the laboratory of Dr. Satoshi Ikemoto at National Institute on Drug Abuse (NIDA). His research interests are to understand neural mechanisms of motivation and reward. Especially, he investigates hypothalamic nuclei in reward-seeking and nicotine reinforcement behavior, using optogenetic and fiber photometry procedures in freely moving mice. In addition, he is developing a new mouse nicotine self-administration model.
Yosuke received his Ph.D. from Hiroshima University in Japan where he studied neurotoxic mechanism of organophosphorus agent such as sarin in vitro. He then joined the Department of Anatomy at Shimane University School of Medicine where he studied the projections of parabrachial neurons to orexin neurons. Yosuke enjoys basketball, jogging, biking, and hiking outside of the lab.
Nicholas Beacher, Ph.D. (NIDA)

Nicholas is a Postdoctoral Fellow in Dr. Da-Ting Lin’s laboratory within the Neural Engineering Section of the National Institute on Drug Abuse (NIDA). As a CCB Fellow, Nicholas uses miniScope in vivo imaging to record neurons from freely moving transgenic rats to study how reward seeking behaviors are correlated with limbic neural activity. His longterm goal is to use miniScopes to uncover how choices are represented in the brain such as when animals choose to take, or ignore, opportunities to self-administer drugs of abuse.
Nicholas received his Ph.D. in Psychology: Behavioral and Systems Neuroscience from Rutgers University in 2020. At Rutgers he used electrophysiological techniques to study drug cue processing in rats self-administering cocaine. In his free time, Nicholas enjoys playing sports, fishing, and kayaking.
Adam Caccavano, Ph.D. (NICHD)
Adam is a post-doctoral CCB fellow interested in neuronal diversity and inhibitory micro-circuitry. In the lab of Dr. Chris McBain, Adam’s research focuses on how opioids modulate inhibition across different brain regions, species, and development.
Adam started his training in physics, earning a B.S. from the University of Oregon and M.S. from Portland State University. He then completed his Ph.D. in neuroscience at Georgetown University in the lab of Dr. Stefano Vicini, where his research focused on how inhibitory microcircuits become disrupted in Alzheimer’s disease.
Ying Duan, Ph.D. (NIDA)

Ying Duan is a postdoctoral fellow in the laboratory of Dr. Yihong Yang at the National Institute on Drug Abuse (NIDA). As a 2021 CCB Fellow, Ying focused on the involvement of lateral habenula circuits in compulsive drug-taking behaviors in rats, combining magnetic resonance imaging with pharmacological or DREADDs modulation technologies.
Ying received her Ph.D. in healthy psychology at the University of the Chinese Academy of Sciences in 2019. Her Ph.D. work focused on exploring the roles of L-type calcium channels in incubation of cocaine craving in the tree shrew (Tupaia belangeri) model. During her post-doc training, she is working on exploring neuronal mechanisms on compulsive drug-taking in rats.
Ayland Letsinger, Ph.D. (NIEHS)

Dr. Letsinger is a 4th year postdoctoral fellow in the Ion Channel Physiology Group of the Neurobiology Lab at the National Institute of Environmental Health Sciences under the mentorship of Drs. Jerrel Yakel and Guohong Cui. He is currently studying brain circuits that are responsible for the initiation and persistence of wheel running in mice using fiber photometry and chemogenetics.
Dr. Letsinger received his PhD in Exercise Physiology as he found physical health to be essential for a happy life. He hopes to one day find a way to increase the pleasure associated with physical activity so more people will participate and gain the many benefits.
Thien Nguyen, Ph.D. (NICHD)

Thien is a Postdoctoral Visiting Fellow at the Section on Translational Biophotonics under Dr. Amir Gandjbakhche. In her lab, she involves in many different projects such as development of a wearable device to monitor pregnancy health and utilization of a multimodal NIRS/EEG to identify early neuronal biomarkers of autism disorder spectrum in infants and toddlers. As a CCB fellow, Thien proposed to investigate the correlation between the autistic traits and the frontal functional connectivity during a resting state and during an inhibition task. Her long-term goal is to identify cerebral functional connectivity networks, which can be used to predict autism in infants and toddlers.
Thien received her PhD in biomedical engineering from Gwangju Institute of Science and Technology in 2019. During her PhD program, she developed and applied optical systems to monitor cerebral hemodynamic responses in different cognitive states and to measure tissue oxygen saturation.
Thien can memorize a broad map but often fail to recognize left and right sides. If you ask her direction to go somewhere, it is better to ignore what she says but follow where she points.
Lorenzo Sansalone, Ph.D. (NINDS)

Lorenzo is a postdoctoral scientist in the laboratory of Dr. Zayd Khaliq at the National Institute of Neurological Disorders and Stroke (NINDS) where he studies the cellular neurophysiology of dopaminergic transmission. Lorenzo was first awarded the CCB fellowship in 2021 to explore the intrinsic physiological properties of motor- and non-motor related dopaminergic subpopulations, within the midbrain, in order to better understand how their physiology can shape common phenotypic behaviors observed in pathological conditions involving the basal ganglia, such as Parkinson’s disease (PD), obsessive-compulsive disorder (OCD) and schizophrenia. Lorenzo’s long-term interest is to elucidate unknown neuronal physiological properties and pathways to identify novel biological targets for the development of more effective therapeutics for CNS-related disorders.
Lorenzo earned a Laurea Diploma (BSc + MSc) in Medicinal Chemistry and Pharmaceutical Technologies from the University of Milan (Italy) in 2013 and received a PhD in Organic Chemistry from the University of Miami (USA) in 2018. After a 2-year appointment, as a postdoctoral fellow, in the Department of Neuroscience of the Icahn School of Medicine at Mount Sinai Hospital in New York City, Lorenzo joined the cellular neurophysiology section of NINDS in 2020 as a postdoctoral researcher.
Sudhuman Singh, Ph.D. (NCCIH)

Dr. Sudhuman Singh is a visiting post-doctoral fellow at the Section on Behavioral Neurocircuitry and Cellular Plasticity, led by Dr. Yarimar Carrasquillo at National Center for Complementary and Integrative Health (NCCIH). As a 2021 CCB fellow, Dr. Singh will be investigating cell type and projection specific role of CeA to zona incerta pathway in pain related affective behavior. To achieve this, he will combine aversive behavior, virus based anatomical tracing, in-vivo chemogenetics, optogenetics and fiber photometry approach to characterize and manipulate neuronal pathway.
Dr. Singh is interested in understanding the neural mechanisms underlying cognitive and neuropathological conditions and has trained in multidisciplinary research fields in neuroscience, including sleep, reinforcement learning, and pain. He earned his PhD in sleep biology from Jawaharlal Nehru University, India. Outside the lab, Dr. Singh enjoys walking, experiments in cooking, photography, spending time with family and friends.
Josephin Wagner, M.D. (NIAAA)

Josephin Wagner joined the Section on Clinical Genomics and Experimental Therapeutics (CGET) at NIAAA in September 2020. Her main goal is to understand the pathophysiology and neurobiology of alcohol use disorder and ischemic stroke, studying neuroinflammation, oxidative stress and blood brain barrier changes with epigenetic and pharmacological approaches. Josephin is also the associate investigator and research physician in a human clinical trial using Alirocumab in a Phase 1 study in heavy drinkers.
Josephin earned her MD at Charité - Universitätsmedizin Berlin in Germany and a MS in Medical Biology at the University of Zurich in Switzerland. Working as a researcher and a doctor in the Department of Neurosurgery at the University Hospital in Zurich, she gained a broad background in neuroscience, with specific expertise in molecular changes on the microvascular level after stroke. After her time as a postdoc, her goal is to become a US board-certified psychiatrist.
Third Year Fellows
Sebastiano Bariselli, Ph.D. (NIAAA)

Fetal alcohol exposure has devastating neurobehavioral consequences that protract into adulthood. In the Laboratory for Integrative Neuroscience (LIN) at NIAAA, Sebastiano combines optogenetic, ex vivo and in vivo neuronal activity recordings to investigate how ethanol exposure during early periods of development affects corticostriatal circuits to produce cognitive and motor dysfunctions. Understanding the relative contribution of synaptic and circuit maladaptations in specific brain circuits will expand the paucity of therapeutic interventions currently available for patients affected by Fetal Alcohol Spectrum Disorder (FASD).
Sebastiano received his BSc and MSc in Pharmaceutical Biotechnology from the University of Milano (Italy) in 2009 and 2012. During his PhD, Sebastiano investigated the effects of downregulation of autism spectrum disorder (ASD)-associated genes (SHANK3 and Neuroligin 3) on VTA dopamine neuron function. Sebastiano obtained his PhD in 2016 and moved to NIH in the laboratory of Dr. Kravitz to investigate the effects of hyperdopaminergic states on corticostriatal plasticity in vivo. In 2019, Sebastiano joined the laboratory of Dr. Lovinger, where he is currently investigating the impact of gestational ethanol exposure on different striatal cell types.
Coleman Calva, Ph.D. (NIDA)

Cole is a 2020 CCB Fellow working at the National Institute on Drug Abuse (NIDA) in the laboratory of Dr. Satoshi Ikemoto. Cole’s primary research interests are related to the neural mechanisms underlying risk-taking behavior and the interactions between uncertain environmental stimuli and risk-taking. For his CCB research project, he aims to understand how medial septum glutamate neurons and their functional connections encode information related to uncertainty. Specifically, Cole’s research will combine optogenetics and in-vivo recording methods to investigate how uncertain rewards and punishments modulate the native neuronal activity of these neurons and whether optogenetic manipulations of inputs to these neurons affect uncertainty-driven behavior.
Cole received a B.S. in Biochemistry from North Carolina State University in 2013 and received his Ph.D. in Integrated Biomedical Science from the University of South Carolina in 2019. For his dissertation, he worked under the mentorship of Dr. Jim Fadel and combined immunohistochemistry, in-vivo microdialysis and cognitive behavioral paradigms to investigate the effects of intranasal orexin administration on age-related cognitive decline.
Emma Condy, Ph.D. (NIMH)

Emma is a Research Fellow in the Neurodevelopmental and Behavioral Phenotyping Service (NBPS) at the National Institute of Mental Health. As a 3rd year CCB fellow, her project is investigating the measurement and neural mechanisms of restricted repetitive behaviors (RRBs) in neurodevelopmental disorders under the mentorship of her primary mentor, Dr. Audrey Thurm, and Dr. Amir Gandjbakhche (NICHD). The project first aims to evaluate the psychometric properties of a caregiver RRB questionnaire across individuals with autism spectrum disorder and intellectual disability. Then, using this measure, RRB neural mechanisms will be investigated through functional near-infrared spectroscopy and psychophysiological metrics (e.g., heart rate variability) to interrogate how the central and autonomic nervous system contribute to RRB profiles in autism spectrum disorder and intellectual disability.
Emma received her A.B. in Biology & Psychology from Bryn Mawr College in 2012 and her Ph.D. in Psychology with a concentration in Biological Psychology from Virginia Tech in 2018. Her training has focused on affordable, accessible methods with low participant burden to maximize inclusion in neurodevelopmental disorder research. During her graduate training she gained methodological expertise in psychophysiological measurement to index autonomic nervous system functioning in children with autism spectrum disorder. She then trained in functional near-infrared spectroscopy through the NIH’s Graduate Partnership Program in the Section on Translational Biophotonics (PI: Gandjbakhche, NICHD). Now, she is combining these experiences with her postdoctoral training in behavioral phenotyping through the NBPS (Director: Thurm, NIMH) in her CCB project.
Rosario Jaime-Lara, Ph.D. (NIAAA)

Rosario’s research has focused on studying eating behavior, including the neurophysiology of eating behavior in the context of obesity and health. She was awarded the CCB fellowship in 2020 and her project focused on striatal mitochondrial dysfunction in chemo-sensation and eating behavior, and the activity and phenotype of dopamine neurons following a high fat diet. In 2022 Rosario and Rodolfo Flores were awarded the CCB Seed Grant Fellowship to examine how alcohol seeking behavior in the presence of threats affects approach-avoidance strategies in mice and examine how a history of HFD feeding affects reward-seeking behaviors during conflict.
Rosario received her Ph.D. from the University of Pennsylvania in 2018 and her dissertation focused on nutritional neuroscience. In 2014, she obtained her training as a Family Nurse Practitioner and received her Master’s in Nursing from Columbia University. She received a bachelor’s degree in Nursing from Columbia University and a bachelor’s degree in Biology with an emphasis on neurobiology, physiology, and behavior from The University of California Davis.
Brenton Laing, Ph.D. (NIDA)

Brenton Laing is a postdoctoral fellow in Dr. Yeka Aponte’s lab at the National Institute on Drug Abuse. His project is focused on significant increases in grooming behavior that are triggered following threatening experiences and anterior hypothalamic area activation. He seeks to use manipulations of threat-responsive neurons to reduce stress-induced behavioral changes.
Brenton earned his PhD in Bioenergetics and Exercise Science working with Dr. Hu Huang at East Carolina University. His dissertation examined the effects of hunger and exercise on adaptations in the arcuate nucleus of the hypothalamus. He has combined the expertise he gained in electrophysiology in his doctoral work with optogenetics and calcium imaging during his postdoctoral work to interrogate hypothalamic relay circuits that control threat responding. In his free time he likes to train his dogs and play Jenga.