Each second, living organisms take in sensory input from an ever-changing environment and respond appropriately. Identifying and contextualizing stimuli is critical for survival, and it often necessitates distinguishing between sensory experiences that are similar to each other. Pattern separation characterizes the mechanisms by which neuronal networks extract and highlight differences...
The retina does not act as a simple camera, rather visual information goes through multiple layers of processing before it reaches the brain. Retinal ganglion cells (RGCs) are the output neurons of the retina and process visual information in the retina and then project into the brain. There are over...
Recent development on optogenetic methods offers reliable path to modulate cell activities with high level spatiotemporal precision. Application of this technology in behavior studies significantly improves our understanding in the neural principle that underpin animal behaviors, including ourselves. Full exploitation of optogenetic method in neuroscience behavior studies relies on...
Research on rat whiskers offers knowledge in neuroscience analogous to humans\' sense of touch and inspiration for efficient sensing robotics. The present work investigates the rat whisker system from a mechanical engineering perspective. First, key quasi-static and dynamic properties were quantified in Chapter 2 for individual whiskers in an array,...
A central question in neuroscience is how the brain plans movements. Here, I apply neural data analysis and machine learning methods to better understand both eye and arm movement planning, in particular focusing on naturalistic settings. First, I built encoding models to investigate the factors that led to neural activity...
Previous research has shown that creative insight problem-solving is distinct from systematic analytical problem-solving. Behaviorally, a positive mood has shown to facilitate insights but without knowing the processes that are fundamental to insight, the mechanisms as to how a positive mood facilitates insights have remained unspecified. Here, we investigate the...
Sleep deprivation (Sd) preferentially impairs predictive and adaptive behaviors that shift responses based on the appropriate context. Behavioral studies implicate the frontal lobes as particularly susceptible to Sd. Aging also impairs frontal functioning, and alters the response to Sd. The interaction between age and Sd is poorly understood, and few...
A pyramidal neuron receives thousands of inputs spread throughout its dendritic tree, which it must integrate into a decision about whether or not to fire action-potential output. Since action potentials are the primary means by which these neurons communicate with their network partners, understanding this input-output relationship is critical for...
Many ion channels are localized in specific subcellular domain of the neurons, and the proper localization is critical for the function of ion channels. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels (h channels) are asymmetrically distributed in the CA1 pyramidal neurons, enriched in the distal apical dendrites. H current, generated by h...
The growth cone is a highly specialized motile structure with a distinctive and dynamically variable morphology. Current understanding of actin-based protrusive motility has been formulated in terms of the dendritic nucleation/array treadmilling model for lamellipodial protrusion and the convergent-elongation model for filopodial protrusion, that were based upon results obtained primarily...
A comprehensive understanding of how image processing occurs in the primary visual cortex (V1) requires learning what aspects of neuronal responses are driven by strong feed-forward input from the lateral geniculate nucleus (LGN), and what aspects arise due to the densely recurrent network operating within the cortex itself. From an...
Gonadotropin releasing hormone (GnRH) neurons comprise the final pathway through which the central nervous system exerts its control over the hypothalamic-pituitary-gonadal (HPG) axis. GnRH is released in a pulsatile manner, and conveyed to the anterior pituitary gland to stimulate synthesis and secretion of the gonadotropins, luteinizing hormone (LH) and follicle-stimulating...
A comprehensive understanding of human memory requires both cognitive and neural descriptions of memory processes along with a conception of how memory processing drives behavioral responses and subjective experiences. Noninvasive neuroimaging techniques have greatly extended our understanding of the functional characteristics of human memory, and how neural events give rise...
Information processing in the striatum is crucial for voluntary movement control and associative learning and in the normal condition is subject to balanced dopaminergic and cholinergic modulation. However, in Parkinson's disease (PD) striatal dopamine (DA) level falls because of degeneration of DA neurons in the substantia nigra pars compacta and...
Amyotrophic lateral sclerosis (ALS) is characterized by progressive motoneuron loss. Autopsy from thoracic spinal tissues of sALS patients revealed a significant loss of large motoneurons while medium and small motoneurons were relatively unaffected. Using two-photon microscopy, we observed a soma hypertrophy of neonatal motoneurons in mice overexpressing mutant human G93A-superoxide...