The form and function of neural circuits are shaped by experience during critical periods of development. Recently, our lab discovered an important outcome of critical period plasticity in the visual system, namely, binocular matching of orientation preference, whereby initially randomly aligned orientation preferences become matched in individual cells. Following this...
Worldwide, youth living with perinatally-acquired human immunodeficiency virus (PHIV) are at increased risk for cognitive dysfunction and developmental delay. Effects of the virus, chronic inflammation, and combination antiretroviral therapy (cART) during critical periods of brain development may disrupt normal cognitive development. Neuroimaging studies using structural magnetic resonance imaging (sMRI) allow...
The mouse visual system has recently been shown to possess many of the properties observed in the visual systems of the classically studied carnivores and primates. An ever-expanding genetic toolkit has given researchers who study vision in mice many advantages unavailable in other species.
In this thesis I study the...
Saccharomyces cerevisiae contains several epigenetic elements known as yeast prions. Our laboratory discovered the yeast prion [SWI+], whose protein determinant is Swi1, a subunit of the SWI/SNF chromatin-remodeling complex. Formation of [SWI+] results in abolishment of multicellular features and a partial loss-of-function phenotype of non-glucose carbon source usage. Our laboratory...
Habits are actions taken without conscious consideration of a goal. The distinction between habits and conscious, goal-directed actions has been made for millennia. Only comparatively recently, however, have results from biological psychiatry and neuroscience begun to shed light on the existence of separable neural circuits that underlie our intuitive perception...
Large projection neurons of the cerebellar nuclei (CbN cells), whose activity generates movement, are inhibited by Purkinje cells and excited by mossy fibers. The high convergence, firing rates, and strength of Purkinje inputs predict powerful suppression of CbN cell spiking, raising the question of what activity patterns favor excitation over...
As neuroscience seeks to understand larger, more complicated systems and behaviors, we will require neural recording techniques that can monitor the activity of neurons across the whole brain. The unparalleled data-storage capabilities of DNA, combined with fast, genetically encodable DNA polymerase-based sensors, would allow for "ticker tape"-like recordings of neurons...
In vivo, substantia nigra pars compacta (SNc) dopaminergic neurons exhibit three spiking patterns – irregular, regular, and bursting. These distinct modes of activity are thought to underlie the different roles that dopamine (DA) plays in target structures within the basal ganglia. In particular, burst spiking in SNc DA neurons is...
Psychosocial stress is part of everyday life, and while ubiquitous, stress plays a huge role disease development and treatment. Though the stressor’s intensity, predictability, and frequency (acute vs chronic) are important determinants of disease development, interactions with one’s genetic and epigenetic make-up also play a causal role. Major Depressive Disorder...
Totipotent cells have the highest developmental potential and can only be created by nuclear transfer into oocytes. Identities of maternal factors that can induce this reprogramming remain a mystery. In this report, we demonstrate induction of totipotency on mouse embryonic stem cells by introducing six factors, Hist1h2aa, H3f3b, H1foo, p-Npm2,...