JEONG @ NIH - Research

My research aims to bridge a critical gap in understanding how the dynamic interplay between neurotransmitters and intracellular signaling is translated into circuit-level function and behavior. Specifically, my research focuses on how the mammalian brain implements reinforcement learning and adaptive behaviors through molecular and neural circuit mechanisms, and how these processes are disrupted by addictive substances and psychiatric drugs to drive maladaptive behavior.

Key questions driving my research include:

(1) How do dopamine activity and intracellular messengers like cAMP dynamically regulate synaptic and circuit plasticity during learning?

(2) How do neural circuit dynamics encode, retain, and flexibly update learned behaviors in response to changing contexts?

(3) How do pharmacological agents—including psychiatric drugs and addictive substances—alter these signaling pathway , circuit functions, and behavioral outcomes?

By integrating in vivo optical imaging, molecular and genetic tools, and computational analysis, this work seeks to link molecular mechanisms with systems-level neural function, ultimately advancing therapeutic strategies for addiction and neuropsychiatric disorders.

Reward Processing Circuits in the Basal Ganglia

Neural substrates involved in reward processing and reinforcement learning (RL) are essential for biological organisms to acquire new skills, make decisions, and adapt to changing environments. I investigate how neural circuits in the basal ganglia encode reinforcement and error signals that drive learning and behavioral adaptation. Additionally, my research explores how pharmacological interventions and addictive drugs disrupt these processes.

Using in-vivo optical methods and animal behavior models, I examine how dopamine neuromodulation is differentially involved in reward-based learning and drug responses across striatal subregions (link). I am also interested in understanding the intracellular signaling mechanisms and neural circuit dysfunction associated with chronic exposure to psychoactive drugs, including addictive substances, selective receptor agonists, and pain management drugs. My previous and ongoing studies involve substance exposure models, including cocaine, alcohol, and THC. Ultimately, this work aims to advance our understanding of the neural mechanisms underlying reward-based learning and behavioral regulation, and to provide new insights into pharmacological treatments for neurological disorders associated with basal ganglia circuitry.

Adaptive and Flexible Neural Dynamics in the Cortex

The brains of humans and many other animals possess an extraordinary ability to flexibly organize complex and dynamic movement sequences through reinforcement learning. How do brain circuits compute behavioral information and regulate motor output during this process? My research explores the cortical circuits and neural dynamics involved in organizing complex behaviors. Using in-vivo optical imaging and computational techniques, I focus on decoding the neural network dynamics of cortical microcircuits that control action sequence, reinforce motor learning, and enable flexible motor behaviors. In my most recent project (link), I use large-scale single-cell calcium imaging and opto/chemogenetic manipulations in freely behaving mice to identify the cortical microcircuit dynamics that actively regulate action sequences in a learning- and task-dependent manner. This finding has implications for understanding adaptive and flexible behavior and the computational roles of cortical circuits.