Navigating through the world is typically a multisensory experience. Mammals are believed to navigate using a cognitive map of space stored in the hippocampus. Yet, it is unclear how and whether spatial information of different sensory modalities can contribute to this map. A major barrier to addressing this question has...
Movement and sensing fundamentally works in a synergistic manner. Animal's sensory organs --- be they independently movable like eyes or requiring whole body movement as in the case of electroreceptors --- are actively manipulated throughout stimulus-driven active sensing behaviors. Though these sensing-related motions have been individually reported and analyzed across...
A one-time, unilateral injury to the developing brain can interrupt the typical process of development and result in motor impairments that evolve over the course of the whole life-span. The timing of injury relative to neural development has implications for the continued refinement of the nervous system and the descending...
Research on how sleep contributes to memory has blossomed in recent years. These studies have generally focused on whether or not sleep impacts various types of memory independently. An open question is whether sleep interactively influences different memory types. My research focuses on two types of memory—specificity and generalization. Whereas...
The exchange of information in the brain is accomplished through sequences of action potentials that result from the integration of local microcircuits. Unraveling the connectivity of the neurons that constitute these microcircuits and how they contribute to network activity is vital for understanding how information is relayed through the brain...
In the vertebrate retina, neurons process visual signals, generating feature selectivity in their activity levels. We use computational models to understand these behaviors by interpreting them mathematically. One component of this analysis is the spatial selectivity or receptive field, a property found in all visual sensory neurons. The neurons found...
We present a biophysical model of GCaMP6f calcium fluorescence in CA1 pyramidal neuron dendrites based upon results from imaging and electrophysiology experiments. This work was completed using experimental results from the laboratory of Professor Daniel Dombeck, Department of Neurobiology. Constraining the model to reproduce different objectives --- from in-vitro and...
Understanding associative memory is fundamental for a variety of neurological and neurodegenerative diseases, however, a large proportion of this research has excluded female subjects due to unsubstantiated bias. By including intact females, ovariectomized females and males in the study of associative memory, clear sex differences in acquisition emerged. Female mice...
Prions are self-perpetuating, alternative protein conformations associated with neurological diseases and normal cellular functions. Saccharomyces cerevisiae contains many endogenous prions – providing a powerful system to study prionization. Previously, the Li Lab demonstrated that Swi1, a component of the SWI/SNF chromatin-remodeling complex, can form the prion [SWI+]. A small region,...
Astrocytes are the most abundant cell type in the brain, yet the mechanisms involved in astrocyte differentiation and the level of astrocyte heterogeneity in the CNS, particularly in the human cortex, is largely unknown due to the lack of subtype-specific astrocyte markers and inaccessibility of human brain tissue. Here we...
Coiled-coil helix coiled-coil helix domain containing 10 (CHCHD10) is a nuclear gene that encodes for a mitochondria-enriched protein of unknown function. This type of protein is typically imported into mitochondria via the disulfide relay system which facilitates the formation of disulfide bridges between each coiled-coil helix, resulting in maintenance of...
Understanding associative memory is fundamental for a variety of neurological and neurodegenerative diseases, however, a large proportion of this research has excluded female subjects due to unsubstantiated bias. By including intact females, ovariectomized females and males in the study of associative memory, clear sex differences in acquisition emerged. Female mice...
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by motor neuron (MN) degeneration and resulting in progressive paralysis and death. ALS is genetically heterogeneous, disease pathophysiology is not completely understood, and there are no effective drug therapies. To develop broadly applicable therapeutics, we examine disease mechanisms in the...
Movement is achieved by combining synaptic inputs from various sources and activating motor unit populations. Motor units are the quantal elements of motor control which act as a neuromechanical transducer that converts sensory inputs into motor output. Because of the tight neuromuscular junctions between motoneuron axon terminals and a large...
Mitochondria-lysosome contacts are recently identified sites for mediating crosstalk between both organelles, but their role in normal and diseased human neurons remains unknown. We used super-resolution and live-cell microscopy in human iPSC-derived neurons to demonstrate that mitochondria-lysosome contacts can dynamically form in the soma, axons, and dendrites of human neurons,...
Chemokines, such as Stromal Derived Factor 1 (SDF-1 or CXCL12) and their G protein coupled receptors (GPCRs) are well known regulators of the development and functions of numerous tissues. CXCL12 has two receptors: CXCR4 and CXCR7 or atypical chemokine receptor 3 (ACKR3). CXCR7 has been described as an atypical “biased”...
Coordinated movement relies on the precise and controlled activation of populations of motor units, which convert the commands of the nervous system into muscle forces. Motor unit firing patterns are often nonlinear and generated through the response to a combination of ionotropic excitatory and inhibitory commands, as well as metabotropic...
Processing of sensory information in the brain is a pervasive and fundamental phenomenon across animal species and is involved in both "hard-wired" innate responses as well as learned and adaptive behaviors. Here, I show that the avoidance of hot temperature, a simple innate behavior, contains unexpected plasticity and complex processing...
Inter-organelle contact sites have become increasingly appreciated as important regulators of cellular homeostasis, and disruption of inter-organelle contact site dynamics and function has been observed in various pathologies. Recently, inter-organelle contact sites between mitochondria and lysosomes were discovered, offering a new mechanism by which these two organelles may directly interact,...
Social engagement, or shared attention between a child and caregiver, is a critical process for language and social development. Although previous EEG studies have investigated child social processing in closely controlled, experimental studies, no study has examined the interactive, reciprocal process of naturalistic social engagement. In my first paper, we...