Medicine and Health Sciences Commons^™

Perceptual Fatigability And Neuromuscular Responses During A Sustained, Isometric Forearm Flexion Muscle Action Anchored To A Constant Level Of Perceived Exertion, Robert W. Smith, John Paul V. Anders, Tyler J. Neltner, Jocelyn E. Arnett, Joshua L. Keller, Terry J. Housh, Richard J. Schmidt, Glen O. Johnson

Journal for Sports Neuroscience

Objective: The purpose of the present study was to examine the fatigue-induced changes in torque, and the electromyographic (EMG) and mechanomyographic (MMG) responses during a sustained submaximal, isometric forearm flexion muscle action anchored to a constant rating of perceived exertion (RPE). Methods: Eleven women (mean ± SD: age = 20.5 ± 1.9 yrs.; height = 169.9 ± 6.6 cm; body mass = 73.2 ± 15.9 kg) performed 2, 3s forearm flexion maximal voluntary isometric contractions (MVIC) before a sustained isometric muscle action anchored to RPE = 7 until task failure (defined as torque that would require RPE > 7, or the …

Cortical Dynamics Of Language, Kiefer Forseth

Dissertations & Theses (Open Access)

The human capability for fluent speech profoundly directs inter-personal communication and, by extension, self-expression. Language is lost in millions of people each year due to trauma, stroke, neurodegeneration, and neoplasms with devastating impact to social interaction and quality of life. The following investigations were designed to elucidate the neurobiological foundation of speech production, building towards a universal cognitive model of language in the brain. Understanding the dynamical mechanisms supporting cortical network behavior will significantly advance the understanding of how both focal and disconnection injuries yield neurological deficits, informing the development of therapeutic approaches.

Multimodal Computational Modeling Of Visual Object Recognition Deficits But Intact Repetition Priming In Schizophrenia, Pejman Sehatpour, Anahita Bassir Nia, Devin Adair, Zhishun Wang, Heloise M. Debaun, Gail Silipo, Antigona Martinez, Daniel C. Javitt

Publications and Research

The term perceptual closure refers to the neural processes responsible for “filling-in” missing information in the visual image under highly adverse viewing conditions such as fog or camouflage. Here we used a closure task that required the participants to identify barely recognizable fragmented line-drawings of common objects. Patients with schizophrenia have been shown to perform poorly on this task. Following priming, controls and importantly patients can complete the line-drawings at greater levels of fragmentation behaviorally, suggesting an improvement in their ability to performthe task. Closure phenomena have been shown to involve a distributed network of cortical regions, notably the lateral …

Core Neuropsychological Measures For Obesity And Diabetes Trials: Initial Report, Kimberlee D'Ardenne, Cary R. Savage, Dana Small, Uku Vainik, Luke E. Stoeckel

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Obesity and diabetes are known to be related to cognitive abilities. The Core Neuropsychological Measures for Obesity and Diabetes Trials Project aimed to identify the key cognitive and perceptual domains in which performance can influence treatment outcomes, including predicting, mediating, and moderating treatment outcome and to generate neuropsychological batteries comprised of well-validated, easy-to-administer tests that best measure these key domains. The ultimate goal is to facilitate inclusion of neuropsychological measures in clinical studies and trials so that we can gather more information on potential mediators of obesity and diabetes treatment outcomes. We will present the rationale for the project and …

Mechanisms Of Value-Biased Prioritization In Fast Sensorimotor Decision Making, Kivilcim Afacan-Seref

Dissertations and Theses

In dynamic environments, split-second sensorimotor decisions must be prioritized according to potential payoffs to maximize overall rewards. The impact of relative value on deliberative perceptual judgments has been examined extensively, but relatively little is known about value-biasing mechanisms in the common situation where physical evidence is strong but the time to act is severely limited. This research examines the behavioral and electrophysiological indices of how value biases split-second perceptual decisions and the possible mechanisms underlying the process. In prominent decision models, a noisy but statistically stationary representation of sensory evidence is integrated over time to an action-triggering bound, and value-biases …

The Effectiveness Of The Natural Ear On Adults Ability To Accurately Match Pitch, Kendra Nicole Rosales

Open Access Theses & Dissertations

Background: Many theories, such as oral motor, perceptual, and sensorimotor deficits, have been posited to explain inaccurate pitch matching abilities. The current study identifies with the sensorimotor deficit theory and found it to be the most plausible explanation for inaccurate singing abilities. The Natural Ear (NE) program was designed to process voice productions in real-time and filter out the discordant harmonics, allowing a person to hear only their F0.

Purpose: The purpose of this study was to examine the effectiveness of the Natural Ear program in increasing pitch matching accuracy in singers.

Methods: A total of 50 participants were included …

An Integrative Neurological Model For Basic Observable Human Behavior, Ryan M. Francis

Calvert Undergraduate Research Awards

The scientific method uncovers information from the natural world in small increments. This spurs the design of models to explain how the pieces fit together and to identify future targets of research. This is especially the case in psychology, where visualizing concepts is an advantageous practice. One all too common criticism of cognitive and behavioral models in psychology is the lack of a biological basis. This paper aims to alleviate part of this issue by integrating currently understood biological and neurological mechanisms that drive psychological phenomena into a predictive and descriptive model for basic human behavior. To accomplish this task, …

Prefrontal Cortical Microcircuits Bind Perception To Executive Control, Ioan Opris, Lucas Santos, Greg A. Gerhardt, Dong Song, Theodore W. Berger, Robert E. Hampson, Sam A. Deadwyler

Neuroscience Faculty Publications

During the perception-to-action cycle, our cerebral cortex mediates the interactions between the environment and the perceptual-executive systems of the brain. At the top of the executive hierarchy, prefrontal cortical microcircuits are assumed to bind perceptual and executive control information to guide goal-driven behavior. Here, we tested this hypothesis by comparing simultaneously recorded neuron firing in prefrontal cortical layers and the caudate-putamen of rhesus monkeys, trained in a spatial-versus-object, rule-based match-to-sample task. We found that during the perception and executive selection phases, cell firing in the localized prefrontal layers and caudate-putamen region exhibited similar location preferences on spatial-trials, but less on …

Detecting Structure In Glass Patterns: An Interocular Transfer Study, Dawn Vreven, Jarrod Berge

Dawn L Vreven

Glass patterns are visual stimuli used here to study how local orientation signals are spatially integrated into global pattern perception. We measured a form aftereffect from adaptation to both static and dynamic Glass patterns and calculated the amount of interocular transfer to determine the binocularity of the detectors responsible for the perception of global structure. Both static and dynamic adaptation produced significant form aftereffects and showed a very high degree of interocular transfer, suggesting that Glass-pattern perception involves cortical processing beyond primary visual cortex. Surprisingly, dynamic adaptation produced significantly greater interocular transfer than static adaptation. Our results suggest a functional …

Recalibrating The Auditory System: A Speed–Accuracy Analysis Of Intensity Perception, Yoav Arieh, Lawrence E. Marks

Department of Psychology Faculty Scholarship and Creative Works

Recalibration in loudness perception refers to an adaptation-like change in relative responsiveness to auditory signals of different sound frequencies. Listening to relatively weak tones at one frequency and stronger tones at another make the latter appear softer. The authors showed recalibration not only in magnitude estimates of loudness but also in simple response times (RTs) and choice RTs. RTs depend on the sound intensity and may serve as surrogates for loudness. Most important, the speeded classification paradigm also provided measures of errors. RTs and errors can serve jointly to distinguish changes in sensitivity from changes in response criterion. The changes …