Research areas

Neurons convert synaptic inputs arriving onto dendrites into action potentials that propagate outward along axons. Back-propagating action potentials (bAPs) also go from soma into dendrites and interact with synaptic inputs to strengthen or weaken individual synapses. During this process, neuronal dendrites are not a passive cable; rather, dendrites actively generate local Na+ and Ca2+ spikes. These voltage-gated conductances control intrinsic neuronal properties and single-neuron computations, thus affecting synaptic plasticity rules.

Synaptic plasticity is the cellular basis of memory formation that controls the efficacy of communications among neuronal ensembles. Our ability to learn and recall deteriorates over the course of life in both normal and disease states. The root cause has been associated with dysfunction in intrinsic neuronal properties (e.g., membrane excitability), dendritic integration, and synaptic plasticity. However, we currently lack a deep understanding of the critical cellular and molecular mechanisms that generate and maintain memory.

The overarching aim of our lab is to understand the mechanisms of learning and memory at the levels of synaptic plasticity, dendritic biophysics, and neuronal ensembles. We develop molecular, optical, and computational tools for spatiotemporally mapping bioelectric activities to elucidate single-neuron computations and plasticity rules in behaving animals. These measurements will lay the groundwork to understand the molecular mechanisms of memory, with the ultimate goal of delaying or reversing memory dysfunctions. We further aim to extend these insights into the realm of brain-machine interface.

Major interest

Molecular and optical tool development for voltage imaging
1. Developing new voltage sensors with rationalized design and directed evolution
2. Improving membrane trafficking of the voltage sensors and channelrhodopsins
3. Advancing optical instruments for imaging with high resolution in space and time

Mechanisms of learning and memory
1. Exploring fundamental rules of memory formation and maintenance from molecules to systems
2. Understanding the roles of diverse cell types and neuromodulatory circuits in memory
3. Discovering new methods to improve or reverse memory in health and disease

Signal processing in dendrites
1. Exploring single-neuron computations, signal processing, and input-output functions
2. Understanding local circuit engagement and excitation-inhibition (E-I) balance
3. Elucidating the mechanisms of dendritic excitability and neurodegeneration

Advisor Professor : Park, Pojeong
Optical Neurophysiology Lab Homepage