The Neural Substrates Of Multisensory Speech Perception,
2011
University of Texas Graduate School of Biomedical Sciences at Houston
The Neural Substrates Of Multisensory Speech Perception, Audrey R. Nath
Dissertations & Theses (Open Access)
Comprehending speech is one of the most important human behaviors, but we are only beginning to understand how the brain accomplishes this difficult task. One key to speech perception seems to be that the brain integrates the independent sources of information available in the auditory and visual modalities in a process known as multisensory integration. This allows speech perception to be accurate, even in environments in which one modality or the other is ambiguous in the context of noise. Previous electrophysiological and functional magnetic resonance imaging (fMRI) experiments have implicated the posterior superior temporal sulcus (STS) in auditory-visual integration of …
Neural Spike Renormalization. Part I — Universal Number 1,
2011
University of Nebraska-Lincoln
Neural Spike Renormalization. Part I — Universal Number 1, Bo Deng
Department of Mathematics: Faculty Publications
For a class of circuit models for neurons, it has been shown that the transmembrane electrical potentials in spike bursts have an inverse correlation with the intra-cellular energy conversion: the fewer spikes per burst the more energetic each spike is. Here we demonstrate that as the per-spike energy goes down to zero, a universal constant to the bifurcation of spike-bursts emerges in a similar way as Feigenbaum’s constant does to the period-doubling bifurcation to chaos generation, and the new universal constant is the first natural number 1.
Neural Spike Renormalization. Part Ii — Multiversal Chaos,
2011
University of Nebraska - Lincoln
Neural Spike Renormalization. Part Ii — Multiversal Chaos, Bo Deng
Department of Mathematics: Faculty Publications
Reported here for the first time is a chaotic infinite-dimensional system which contains infinitely many copies of every deterministic and stochastic dynamical system of all finite dimensions. The system is the renormalizing operator of spike maps that was used in a previous paper to show that the first natural number 1 is a universal constant in the generation of metastable and plastic spike-bursts of a class of circuit models of neurons.
Orbitofrontal Cortex Provides Cross-Modal Valuation
Of Self-Generated Stimuli,
2011
University of Toronto
Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner
Department of Political Science: Faculty Publications
Prior research has shown that the orbitofrontal cortex (OFC) plays an important role in the representation of the evaluation of stimuli, regardless of stimulus modality. Based on these findings, researchers have proposed that the OFC serves a common currency function, allowing for the direct comparison of different types of perceptual stimuli (e.g. food, drink, money). The present study was designed to extend this research and investigate whether these same regions of OFC that have been identified in previous research are involved in evaluating imagined stimuli. Specifically, we asked participants to draw on prior attitudinal knowledge to generate internal representations of …
Motor Demand-Dependent Improvement In Accuracy Following Low-Frequency Transcranial Magnetic Stimulation Of Left Motor Cortex.,
2010
West Virginia University
Motor Demand-Dependent Improvement In Accuracy Following Low-Frequency Transcranial Magnetic Stimulation Of Left Motor Cortex., Cathrin Buetefisch, Benjamin Hines, Linda Shuster, Paola Pergami, Adam Mathes
Linda Shuster
No abstract provided.
Serotonin Transporter (5-Httlpr) Genotype And Childhood Trauma Are Associated With Individual Differences In Decision Making,
2010
Selected Works
Serotonin Transporter (5-Httlpr) Genotype And Childhood Trauma Are Associated With Individual Differences In Decision Making, Scott Stoltenberg
Scott F. Stoltenberg
The factors that influence individual differences in decision making are not yet fully characterized, but convergent evidence is accumulating that implicates serotonin (5-HT) system function. Therefore, both genes and environments that influence serotonin function are good candidates for association with risky decision making. In the present study we examined associations between common polymorphisms in the serotonin transporter gene (SLC6A4; 5-HTTLPR and rs25531), the experience of childhood trauma and decision making on the Iowa gambling task (IGT) in 391 (64.5% female) healthy Caucasian adults. Homozygosity for the 5-HTTLPR L allele was associated with riskier decision making in the first block of …
Tracking The Flow Of Information Through The Hippocampal Formation In The Rat,
2010
University of Texas Graduate School of Biomedical Sciences at Houston
Tracking The Flow Of Information Through The Hippocampal Formation In The Rat, Joshua P. Neunuebel
Dissertations & Theses (Open Access)
The hippocampus receives input from upper levels of the association cortex and is implicated in many mnemonic processes, but the exact mechanisms by which it codes and stores information is an unresolved topic. This work examines the flow of information through the hippocampal formation while attempting to determine the computations that each of the hippocampal subfields performs in learning and memory. The formation, storage, and recall of hippocampal-dependent memories theoretically utilize an autoassociative attractor network that functions by implementing two competitive, yet complementary, processes. Pattern separation, hypothesized to occur in the dentate gyrus (DG), refers to the ability to decrease …
Eye Movement Measures Of Cognitive Control In Children With Tourette Syndrome,
2010
University of Texas Graduate School of Biomedical Sciences at Houston
Eye Movement Measures Of Cognitive Control In Children With Tourette Syndrome, Cameron B. Jeter
Dissertations & Theses (Open Access)
Tourette Syndrome begins in childhood and is characterized by uncontrollable repetitive actions like neck craning or hopping and noises such as sniffing or chirping. Worst in early adolescence, these tics wax and wane in severity and occur in bouts unpredictably, often drawing unwanted attention from bystanders. Making matters worse, over half of children with Tourette Syndrome also suffer from comorbid, or concurrent, disorders such as attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). These disorders introduce anxious thoughts, impulsivity, inattention, and mood variability that further disrupt children with Tourette Syndrome from focusing and performing well at school and home. …
A Comparison Of Three Computer-Based Methods Used To Determine Emg Signal Amplitude,
2010
University of Texas of the Permian Basin
A Comparison Of Three Computer-Based Methods Used To Determine Emg Signal Amplitude, Doug Renshaw
Doug Renshaw
No abstract provided.
Efficient Encoding Of Vocalizations In The Auditory Midbrain,
2010
Portland State University
Efficient Encoding Of Vocalizations In The Auditory Midbrain, Lars Andreas Holmstrom
Systems Science Friday Noon Seminar Series
An important question in sensory neuroscience is what coding strategies and mechanisms are used by the brain to detect and discriminate among behaviorally relevant stimuli. To address the noisy response properties of individual neurons, sensory systems often utilize broadly tuned neurons with overlapping receptive fields at the system's periphery, resulting in homogeneous responses among neighboring populations of neurons. It has been hypothesized that progressive response heterogeneity in ascending sensory pathways is evidence of an efficient encoding strategy that minimizes the redundancy of the peripheral neural code and maximizes information throughput for higher level processing. This hypothesis has been partly supported …
Metastability And Plasticity In A Conceptual Model Of Neurons,
2010
University of Nebraska - Lincoln
Metastability And Plasticity In A Conceptual Model Of Neurons, Bo Deng
Department of Mathematics: Faculty Publications
For a new class of neuron models we demonstrate here that typical membrane action potentials and spike-bursts are only transient states but appear to be asymptotically stable; and yet such metastable states are plastic — being able to dynamically change from one action potential to another with different pulse frequencies and from one spike-burst to another with different spike-per-burst numbers. The pulse and spike-burst frequencies change with individual ions’ pump currents while their corresponding metastable-plastic states maintain the same transmembrane voltage and current profiles in range. It is also demonstrated that the plasticity requires two one-way ion pumps operating in …
