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Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute Jan 2020

Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute

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High cognitive workload occurs when excessive working memory resources have been deployed to resolve sensory and cognitive processing, resulting in decremented task performance. The P300 event-related potential (ERP) component has shown sensitivity to cognitive load, and it was hypothesized that an attenuated P300 amplitude could be indicative of high cognitive load. We tested this hypothesis by having eight participants complete two continual performance tasks at increasing workload levels while simultaneously performing an oddball task, evoking P300 ERPs in either the auditory or tactile sensory channel. In our experiment, electroencephalographic recordings were collected over the parietal region to observe the P300 …


Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris Jan 2020

Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris

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Kv2.1 channels mediate slow-activating K+ rectifier current within the membrane of spinal motoneurons (MNs), and they are known to co-localize with other synapses and ion channels. Although Kv2.1 channels are suggested to regulate MN excitability, little research has gone into investigating its potential contribution to MN-altered excitability in Amyotrophic Lateral Sclerosis (ALS). Using the male SOD1-G93A mouse model of ALS, we examined Kv2.1 cluster area and density in lumbar MNs at four key stages of disease progression. In our experiments, MNs were separated by type via SK3 immunoreactivity in order to isolate and compare the responses of disease-resistant (slow; SK3+) …


Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh Jan 2020

Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh

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This thesis explores the interaction between emotions and visual perception using large scale spatial environment as the medium of this interaction. Emotion has been documented to have an early effect on scene perception (Olofsson, Nordin, Sequeira, & Polich, 2008). Yet, most popularly-used scene stimuli, such as the IAPS or GAPED stimulus sets often depict salient objects embedded in naturalistic backgrounds, or “events” which contain rich social information, such as human faces or bodies. And thus, while previous studies are instrumental to our understanding of the role that social-emotion plays in visual perception, they do not isolate the effect of emotion …


Characterization Of B3galt2 And Heg1 Expression In Dorsal Root Ganglia, Alexander H. Nguyen Jan 2020

Characterization Of B3galt2 And Heg1 Expression In Dorsal Root Ganglia, Alexander H. Nguyen

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Proprioception provides unique sensory feedback about the body’s orientation in space and this sensation is essential for creating specific motor functions and coordinated movement. During neurogenesis, unique genetic markers are expressed and classified as early, transient/middle, and late markers depending on their timing of expression. This study focuses on the expression patterns of two late markers: Heg1 and B3galt2. We investigated how expression of these two markers respond to peripheral nerve injury (PNI). We cloned and generated riboprobes to detect expression of B3galt2 and Heg1 in DRGs using in situ hybridization after transection of the sciatic nerve. B3galt2 hybridization in …


Protocol Development And Optimization For Rnls Mouse Characteristic Assessment, Hasan Farid Jan 2020

Protocol Development And Optimization For Rnls Mouse Characteristic Assessment, Hasan Farid

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Protocol development and optimization are vital in the scientific method process. By having accurate protocols, one can properly assess the characteristics of their animal model for any given experiment. One animal newly adopted in our lab was the novel regulatable nuclear localization sequence (rNLS) mouse model. This novel mouse model displays symptoms of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal dementia (FTD), after the accumulation of the hTDP-43 (TAR DNA-binding protein 43) aggregate in the central nervous system. The expression of this protein occurs after the removal of deoxycycline from the mouse’s food source. Once the removal of the drug, this …


Visual Sampling With The Eeg Alpha Oscillation, Kevin Eugene Alexander Jan 2020

Visual Sampling With The Eeg Alpha Oscillation, Kevin Eugene Alexander

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The posterior alpha rhythm, seen in human electroencephalograms (EEG), is posited to originate from cycling inhibitory/excitatory states of visual relay cells in the thalamus, which could result in discrete sampling of visual information. Here, we tested this hypothesis by presenting light flashes at perceptual threshold intensity through closed eyelids to 20 participants during times of spontaneous alpha oscillations. Alpha phase and amplitude were calculated relative to each individual’s retina-to-V1 conduction delay, estimated by the individuals’ C1 visual-evoked potential latency. Our results show that an additional 20.96% of stimuli are observed when afferenting at V1 during an alpha wave trough (272.41°) …