PROJECT SUMMARY The monoamines, which include dopamine, norepinephrine, and serotonin, are evolutionarily conserved neurotransmitters that modulate the activity of excitatory and inhibitory neurons throughout the entire brain, and are thus essential for diverse aspects of physiology and behavior. Abnormalities of monoamine systems contribute to numerous brain disorders including schizophrenia, depression, and Parkinson's disease.
Project summary: Consolidating transient sensory experiences into long-lasting memories is a fundamental function of the brain, linked to synaptic plasticity. The importance of sleep for promoting this process, and the disruptive effect of sleep deprivation on it, have been appreciated for nearly a century.
Abstract Short-term memory (STM) is a core cognitive function, critical for reasoning, decision-making, and flexible behavior. Though it has been recognized as a key function of interest for many decades, the critical neural substrate of STM is little understood.
Abstract Sleep is essential for the maintenance of our cognition and neurological functions, and both quality and quantity of sleep are critical. We likely have known this for the entire human history. Yet, we remain astonishingly ignorant on how the quality and quantity of sleep are regulated. Excitingly, nature has provided us a very small number of human subjects who are genetically wired to sleep shorter hours per day (thus more efficiently). These people usually live a long and healthy (both physically and mentally) life.
Abstract The flow of visual information from the retina, through the dorsal lateral geniculate nucleus (dLGN) to the cortex, is regulated by behavior. However, the dynamic circuit interactions that occur in the dLGN of awake animals, and their modulation by behavior, have yet to be revealed. The purpose of this proposal is to develop tools to determine how inhibitory circuits of the dLGN (which utilize the neurotransmitter gamma amino butyric acid, GABA) interact in vivo, and how they collectively shape vision in the context of behavior.
Summary Enormous progress has been made about the neural substrates of Pavlovian fear conditioning. In this paradigm, the association between an initially neutral sensory stimulus with an aversive event (footshock) leads to the transformation of the neutral stimulus into a conditioned stimulus (CS) that elicits fear responses in the form of immobility, potentiated startle, changes in heart rate, etc, which were not evoked by the neutral sensory stimulus.
ABSTRACT We will use our expertise in somatosensory organization and plasticity to develop novel and automated solutions for cell identification based upon neural activity, in order to decode the algorithms neural circuits use for information processing. Extracellular recordings in sensory cortex have been thought to primarily represent excitatory neuron activity, since these cells comprise ~80% of the total cell population.
Project Summary/Abstract The goal of this exploratory research project is to improve understanding about the mechanisms by which mammalian neural circuits decode environmental chemosensory information and use that information to support survival and reproduction. Specifically, the proposed research will investigate cell type-specific neural codes in the parallel brain pathways of the mouse accessory olfactory system (AOS).
Summary Multimodal sensory information is converged through poly-synaptic pathways to the hippocampus to form integrated representations and encode memories of the world, which in turn guide our future behavior through multiple poly-synaptic downstream pathways. It is well known that each of the brain regions in this circuit consists of various neuronal cell types or groups which are distinct in connectivity and functions.
Abstract The prefrontal cortex is thought to play a crucial role in cognitive flexibility, in part by updating a person's expectations about the external world and the likely consequences of candidate actions based on the feedback gained from past actions. Deficits in this form of cognition occur in multiple psychiatric conditions in which prefrontal cortex is implicated. Despite much research, the mechanisms by which prefrontal neural circuits contribute to flexible decision-making and switches in cognitive strategy remain unclear.
