NERD Lab Neural Engineering and Rehabilitation Design
The focus of our lab is on developing novel neural interfaces as well as investigating the plasticity mechanism of the brain. Our goal is to reveal underlying mechanisms of brain plasticity that lead to functional recovery from brain damage, which can provide us with vital insight to develop stimulation-based therapies for a broad range of neurological disorders such as stroke. We use a combination of electrophysiological recordings in behaving animals, real-time detection and manipulation of physiological patterns, and perturbation of neural activity in specific circuits during behavior, to determine causal links between physiological phenomena and therapeutic outcomes. In particular, the unique tool we use is optogenetics since it enables us to manipulate neural activity with high spatial and temporal resolution via virally transfected neurons containing light-sensitive ion channels. In addition to its potential for greater spatial resolution and cell-type specificity, this technique offers the significant advantage of artifact-free electrophysiological recording during stimulation. This novel use of optogenetics offers new opportunities to create sophisticated closed-loop stimulation and recording paradigms, and helps us to understand the role of the basic physiological and therapeutic phenomena.
Targeted brain reorganization using optogenetic stimulation in non-human primates
The goal of this project is to reveal underlying mechanisms of brain plasticity that lead to functional connectivity and recovery from injury.
In this project we use activity-dependent stimulation to provide more robust neural plasticity, higher functional and temporal specificity and to restore normal patterns of functional connectivity between brain regions post-injury. Furthermore the use of optogenetics enables us to manipulate neural activity with high spatial and temporal resolution via virally transfected neurons containing light-sensitive ion channels.
This project provides critical insight into the fundamentals of functional connectivity and its role in brain plasticity following injury, demonstrates the power of targeted, activity-dependent cortical stimulation to drive rehabilitative reorganization, and may have a profound impact on future therapeutic interventions for neurological disorders.
Multi-modal large-scale neural interfaces
In order to study the complex relationships between neuronal populations and between neural activity and the vascular system across multiple brain areas over long periods of time, we are designing multi-modal large-scale optogenetic interfaces. Our interfaces will allow for electrical stimulation and recording of neural activity concurrent with optogenetic neuromodulation. With these interfaces we will be able to activate and suppress different regions of the brain to study neural plasticity and develop therapeutic approaches for neurological diseases, such as stroke. We are also designing our interfaces to be compatible with optical imaging approaches, such as optical coherence tomography angiography which is used to study microvasculature. Large-scale imaging of microvasculature over long-term stimulation-based experiments promises to provide critical insight into the relationships between the brain’s microvasculature and neural activity and plasticity. The data collected with these interfaces will provide large-scale, long-term, and multi-modal perspectives for both basic and applied neuroscience.
A lesion-based toolbox to study cortical physiology
Cortex is a highly complex structure responsible for a variety of sophisticated tasks and behaviors including facilitating long-term memory storage, sensation, movement, and vision. Neurological disorders affecting cortex have deleterious effects on these and other important behaviors. Historically, lesioning studies have been crucial for elucidating the functions of broad cortical regions. However, little is understood with respect to the underlying cortical physiology and dynamics following perturbation. Such studies would allow for the development of improved tools and strategies for treating neurological disorders. To address these challenges and accelerate the development of novel and effective therapies, we developed a highly versatile lesion-based toolbox for studying cortical physiology. With this toolbox we have the capability of inducing targeted, modular, and focal ischemic lesions that extend through all cortical layers. Additionally, our system offers a tool to validate the disruption of cortical blood flow and measure lesion sizein vivo. Moreover, our paradigm also allows for the simultaneous recording of the underlying neural activity across the network as lesions develop over time. With our toolbox, lesion volumes can be measured through histological analysis and predicted by a computational model based on modular experimental parameters. The use of these tools in combination with our large-scale neural interfaces (see above) allows us to investigate underlying cortical physiology such as vascular and neural dynamics during the formation of, in the presence of, and during the subsequent recovery from an induced lesion. In combination with behavioral findings, this toolbox can provide critical insights into fundamental cortical functions and drive the development of future rehabilitative therapies for stroke and other neurological disorders.
Studying the underlying mechanisms of post-stroke cognitive impairment
Post-stroke cognitive impairment in various domains from attention deficits to memory problems are very common in stroke victims. The goal of this project is to investigate cortical and hippocampal oscillations following cortical stroke in rats to understand the underlying neural mechanisms.