Neuroscience and Neurobiology Commons^™

An Event-Related Potential Study Of Inhibition To Sugar-Sweetened Beverages, Hanel Watkins

Undergraduate Honors Theses

In the United States, the intake of sugar-sweetened beverages per capita from 1977 to 2002 doubled across all age groups. One factor that may contribute to the consumption of sugar-sweetened beverages is inhibitory control, or the ability to withhold a dominant response in order to correctly respond to one’s environment. Studies suggest that increased recruitment of inhibitory control resources plays a role in decreasing the consumption of high-calorie foods and that strengthening an individual’s inhibitory control may help them manage their food intake. However, the neural response to sugar-sweetened beverages versus non-sweetened beverages is unknown. Thus, we tested event-related potential …

Reduced Gabaergic Signaling At The Axon Initial Segment Decreases Vigilance State Transitioning, Austin John Boren

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sleep is a highly regulated homeostatic process that is disrupted in an estimated 50-70 million Americans. Regulation of sleep depends upon coordinated signaling of multiple neurotransmitter systems. In particular, inhibitory gamma-aminobutyric acid (GABA) signaling is required to suppress wake-active brain regions in order to initiate and maintain sleep states. GABA type A receptors (GABAARs) are ionotropic receptors with subunit compositions uniquely enriched on subcellular domains of target cells. α2 subunit-containing GABAARs are the primary target of GABA released onto the axon initial segment (AIS), a site critical for phasing the oscillatory activity of cortical cells. α2-containing GABAARs have previously been …

Electrophysiological Correlates Of Natural Language Processing In Children And Adults, Margaret Ugolini

Doctoral Dissertations

To understand the causes of differences in language ability we must measure the specific and separable processes that contribute to natural language comprehension. Specifically, we need measures of the three language subsystems – semantics, syntax, and phonology – as they are used during the comprehension of real speech. Event-Related Potentials (ERPs) are a promising approach to reaching this level of specificity. Previous research has identified distinct ERP effects for each of the subsystems – the N400 to semantic anomalies, the Anterior Negativity and P600 to syntactic anomalies, and the Phonological Mapping Negativity to unexpected speech sounds. However, these studies typically …

A Hidden Markov Factor Analysis Framework For Seizure Detection In Epilepsy Patients, Mahboubeh Madadi

Graduate Theses and Dissertations

Approximately 1% of the world population suffers from epilepsy. Continuous long-term electroencephalographic (EEG) monitoring is the gold-standard for recording epileptic seizures and assisting in the diagnosis and treatment of patients with epilepsy. Detection of seizure from the recorded EEG is a laborious, time consuming and expensive task. In this study, we propose an automated seizure detection framework to assist electroencephalographers and physicians with identification of seizures in recorded EEG signals. In addition, an automated seizure detection algorithm can be used for treatment through automatic intervention during the seizure activity and on time triggering of the injection of a radiotracer to …

Electroencephalogram As A Diagnostic Tool In Acquired Brain Injury, Michael Zarra

Senior Theses and Projects

The ability of electroencephalogram (EEG) to be used as a diagnostic device for acquired brain injuries (ABI) has been conceptualized previously. Averaged event-related potentials (ERP) derived from an EEG are suitable as markers of dysfunction however, distinctive properties in the frequency domain have not been established previously. In the present study, we examined pre- existing EEG signal data of healthy adults (HA), mild ABI (mABI), and severe ABI (sABI) human groups. Through Fourier analysis performed in MATLAB, we found that individuals in our sample population (n=80) were able to be categorized into their respective group based on common neuronal activity …

Working Memory And Falls Risk In Older Adults: An Event-Related Potential Study, Yee (Michelle) S. Wong

Electronic Thesis and Dissertation Repository

BACKGROUND: The aging population is rapidly increasing, where currently in North America, the population of older adults (ages 60+) outnumbers the population of children. Falls are a major concern for older adults and their quality of life. Cognitive impairment has been shown to be declined in older adults at-risk for falls, but working memory has not been thoroughly investigated within this population. PURPOSE: To examine differences in Non-Fallers, Moderate Risk for Falls, and Fallers in a working memory task using electroencephalography (EEG). METHODS: Older adults (n=44, female=27) aged 60 – 80 years (m=68.8, SD=4.7) completed two sessions. The first session …

Electrophysiological Biomarkers Of Chemotherapy-Related Cognitive Impairment In Hematological Malignancy Patients, David E. Anderson

Theses & Dissertations

Multiple cancer populations frequently report cognitive impairment following treatment with chemotherapy agents (“chemo-brain”). Impaired neuropsychological performance is commonly reported in cognitive domains of attention and executive function. Understanding neural mechanisms underlying cognitive impairments is essential to developing prevention and rehabilitation strategies. Brain imaging studies frequently show chemotherapy-related impairments within the attentional control network, which is comprised of a constellation of cortical regions that govern reportedly impaired cognitive functions. In the current dissertation research, I developed a novel electrophysiology battery aimed at recording near-instantaneous neural activity within the attentional control network during cognitive task performance. Cancer patients diagnosed with hematological malignancy …

Neural Underpinnings Of Walking Under Cognitive And Sensory Load: A Mobile Brain/Body Imaging Approach, Brenda R. Malcolm

Dissertations, Theses, and Capstone Projects

Dual-task walking studies, in which individuals engage in an attentionally-demanding task while walking, have provided indirect evidence via behavioral and biomechanical measures, of the recruitment of higher-level cortical resources during gait. Additionally, recent EEG and imaging (PET, fNIRS) studies have revealed direct neurophysiological evidence of cortical contributions to steady-state walking. However, there remains a lack of knowledge regarding the underlying neural mechanisms involved in the allocation of cortical resources while walking under increased load. This dissertation presents three experiments designed to provide a greater understanding of the cortical dynamics implicated in processing load (top-down or bottom-up) during locomotion. Furthermore, we …

The Role Of Sleep On Inhibitory Control In Young Children With Attention-Deficit/Hyperactivity Disorder (Adhd), Amanda Cremone

Doctoral Dissertations

Alongside the hallmark symptoms of hyperactivity and inattention, children with attention-deficit/hyperactivity disorder (ADHD) often report having sleep problems. Although sleep deficits are consistently found when evaluated subjectively, impairments in sleep physiology are inconsistent. Compared to typically developing (TD) children, children with ADHD have greater spectral power in the delta (0.5 to 4 Hz) and theta frequency bands (4 to 7 Hz). Moreover, activity in these bands is differentially related to cognitive outcomes in ADHD and TD populations. As such, this dissertation sought to examine relations between sleep physiology and inhibitory control, a primary deficit of ADHD, in young children with …

Neural Processes Underlying Auditory Context Effects, Breanne Yerkes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Auditory information within our natural environments is disorganized and often ambiguous, leaving our auditory systems with a complex task: organizing sound into coherent objects. The auditory system uses both current and prior information to assist in completing this task. The influences of previous context on current perception have been referred to as context effects. A contrastive context effect results in a current perception that is opposite of what is expected based on the physical stimulus properties presented during an immediate context. A facilitative context effect results in a current perception that is the same as the perception during the immediate …

Examination Of Neurocorrelates Of Mild Traumatic Brain Injury In Young Adults, Rachel J. Raucci

Neuroscience Honors Papers

In recent years, there has been an upswing in the number of concussion diagnoses per year in the United States, particularly in young athletes with still-developing brains. Accompanying this recent trend is an increased amount of research on concussions and their long-term impacts. This ongoing research project collects and compares data from concussed and non-concussed individuals using various neuropsychological batteries, self-report surveys and participants’ EEG readings. Data analysis of the results from 51 participants indicates that previously concussed individuals differ from their non-concussed counterparts. Specifically, individuals who have suffered a concussion exhibit specific and occasionally idiosyncratic deficits in executive control …

The Neural Mechanisms Of Musical Rhythm Processing: Cross-Cultural Differences And The Stages Of Beat Perception, Daniel J. Cameron

Electronic Thesis and Dissertation Repository

Music is a universal human behaviour, is fundamentally temporal, and has unique temporal properties. This thesis presents research on the cognitive neuroscience of the temporal aspects of music: rhythm, beat, and metre. Specifically, this work investigates how cultural experience influences behavioural and neural measures of rhythm processing, and the different neural mechanisms (with particular interest in the role of the striatum) that underlie different stages of beat perception, as musical rhythms unfold.

Chapter 1 presents an overview of the existing literature on the perceptual, cognitive, and neural processing of rhythm, including the entrainment of neural oscillations to rhythm and the …

An Investigation Of Short-Term Plasticity In Human Motor Cortex, Matthew Alan Gannon

Graduate Theses and Dissertations

Transcranial magnetic stimulation (TMS) produces a transient magnetic field that activates underlying cortical tissue by eliciting an electrical discharge of the neurons in the targeted area. Repetitive TMS (rTMS) uses patterns of repetitive TMS pulses and has been reliably shown to produce changes in the state of cortical excitability outlasting the time of stimulation. One such protocol that has demonstrated states of increased excitability is intermittent theta burst stimulation (iTBS). This method applies high-frequency bursts (50Hz) of pulses every 200 ms in trains of ten bursts. The effects of and differences between rTMS protocols have been investigated since gaining popularity …

The Relationship Between Time Of Day, Mood, And Electroencephalography (Eeg) Asymmetry, Morgan Tantillo

Honors Projects

Previous researchers have had success in finding a correlation between exercise and an increase in positive mood. Researchers have also found a correlation between time of day and mood. The current study will explore the relationship between time of day, mood, and electroencephalography (EEG) asymmetry. The study utilized a convenient sample of ten undergraduate students at Bowling Green State University. Participants had baseline EEG recordings taken, and then participated in moderate exercise, followed by another EEG recording. Participants’ mood was assessed through a self-reported mood questionnaire before the condition as well as immediately after. Due to multiple statistical tests, the …

Clinical And Physiological Measures Of The Efficacy Of Prospective Memory Treatment, Tessa Bloomquist

Senior Theses and Projects

Prospective memory (PM) involves the ability to form and realize intentions after a time delay (Einstein & McDaniel, 1990). This study examines the relationship between clinical measures of PM and an event-related potential paradigm (West & Ross-Munroe, 2002) before and after Cognitive Rehabilitation Therapy (CRT). Participants with traumatic brain injury (TBI) were assigned to one of two groups, CRT and an active control condition. Electrophysiological and behavioral data were collected while subjects performed a computerized PM measure and the Memory for Intentions Screening Test (MIST) (Raskin, Buckheit, & Sherrod, 2011), a clinical measure. The results from the two groups were …

Effect Of Prior Trauma Exposure On Alpha Amplitude, Heart Rate, And Self-Reported Negative Affect, Gina L. Denoble

All Master's Theses

This study was conducted to investigate whether the number of traumatic events an individual has previously experienced influences that individual’s physiological and psychological reactions when exposed to a negative affective stimulus followed by a mindfulness-based stress reduction (MBSR) intervention. Twenty-eight participants were placed into intact quasi-experimental groups based on their scores on the Traumatic Life Events Questionnaire (TLEQ). The negative affective stimulus consisted of a series of photos bearing negative affective valence. The photos were selected from the International Affective Picture System (IAPS), and paralleled the areas of trauma exposure evaluated by the TLEQ. All participants were exposed to the …

Relationship Between Physiological And Clinical Measures Of Prospective Memory In Individuals With Mild Acquired Brain Injury, Severe Acquired Brain Injury And Healthy Adults, Consuelo M.A Pedro

Senior Theses and Projects

Prospective memory (PM) involves the ability to form and realize intentions after a time delay (Einstein & McDaniel, 1990). This study examines the relationship between clinical measures of PM and an event-related potential paradigm (West & Ross-Munroe, 2002). Electrophysiological and behavioral data were collected while subjects performed a computerized laboratory PM measure and was compared to a clinical measure, the Memory for Intentions Screening Test (MIST) (Raskin, Buckheit, & Sherrod, 2011) in healthy adults (HA), individuals with severe acquired brain injury (sABI) and mild acquired brain injury (mABI). Individuals with sABI performed significantly worse than individuals with mABI and HA …

Development Of A Practical Visual-Evoked Potential-Based Brain-Computer Interface, Nicholas R. Waytowich

Biomedical Engineering Theses & Dissertations

There are many different neuromuscular disorders that disrupt the normal communication pathways between the brain and the rest of the body. These diseases often leave patients in a `locked-in" state, rendering them unable to communicate with their environment despite having cognitively normal brain function. Brain-computer interfaces (BCIs) are augmentative communication devices that establish a direct link between the brain and a computer. Visual evoked potential (VEP)- based BCIs, which are dependent upon the use of salient visual stimuli, are amongst the fastest BCIs available and provide the highest communication rates compared to other BCI modalities. However. the majority of research …

Multichannel Characterization Of Brain Activity In Neurological Impairments, Yalda Shahriari

Biomedical Engineering Theses & Dissertations

Hundreds of millions of people worldwide suffer from various neurological and psychiatric disorders. A better understanding of the underlying neurophysiology and mechanisms for these disorders can lead to improved diagnostic techniques and treatments. The objective of this dissertation is to create a novel characterization of multichannel EEG activity for selected neurological and psychiatric disorders based on available datasets. Specifically, this work provides spatial, spectral, and temporal characterizations of brain activity differences between patients/animal models and healthy controls, with focus on modern techniques that quantify cortical connectivity, which is widely believed to be abnormal in such disorders. Exploring the functional brain …

The Neurophysiology Of Intersensory Selective Attention And Task Switching, Jeremy W. Murphy

Dissertations, Theses, and Capstone Projects

Our ability to selectively attend to certain aspects of the world and ignore others is fundamental to our day-to-day lives. The need for selective attention stems from capacity limitations inherent in our perceptual and cognitive processing architecture. Because not every elemental piece of our environment can be fully processed in parallel, the nervous system must prioritize processing. This prioritization is generally referred to as selective attention. Meanwhile, we are faced with a world that is constantly in flux, such that we have to frequently shift our attention from one piece of the environment to another and from one task to …

Experimental-Computational Analysis Of Vigilance Dynamics For Applications In Sleep And Epilepsy, Farid Yaghouby

Theses and Dissertations--Biomedical Engineering

Epilepsy is a neurological disorder characterized by recurrent seizures. Sleep problems can cooccur with epilepsy, and adversely affect seizure diagnosis and treatment. In fact, the relationship between sleep and seizures in individuals with epilepsy is a complex one. Seizures disturb sleep and sleep deprivation aggravates seizures. Antiepileptic drugs may also impair sleep quality at the cost of controlling seizures. In general, particular vigilance states may inhibit or facilitate seizure generation, and changes in vigilance state can affect the predictability of seizures. A clear understanding of sleep-seizure interactions will therefore benefit epilepsy care providers and improve quality of life in patients. …

Time Frequency Analysis Of Neural Oscillations In Multi-Attribute Decision-Making, Iris Lieuw

Scripps Senior Theses

In our daily lives, we often make decisions that require the use of self-control, weighing trade-offs between various attributes: for example, selecting a food based on its health rather than its taste. Previous research suggests that re-weighting attributes may rely on selective attention, associated with decreased neural oscillations over posterior brain regions in the alpha (8-12 Hz) frequency range. Here, we utilized the high temporal resolution and whole-brain coverage of electroencephalography (EEG) to test this hypothesis in data collected from hungry human subjects exercising dietary self-control. Prior analysis of this data has found time-locked neural activity associated with each food’s …

Electrophysiological And Behavioral Working Memory Differences Between Musicians And Non-Musicians, Benjamin P. Richardson

All Master's Theses

The current study examines the P300 brainwave and working memory differences between musicians and non-musicians. Differences in aspects of recorded electrical brain activity have been used to quantify differences in updating processes of working memory possibly related to differences in amount of music experience. The current study is designed to partially replicate and enhance a method previously implemented in research describing how music experience may be associated with differences in visual processing as well auditory working memory and executive function. Behavioral data were collected using six standardized subtest measures of the TOMAL – II, followed by ERP recordings during a …

Biological Motion Processing In Typical Development And In The Autism Spectrum, Aaron Krakowski

Dissertations, Theses, and Capstone Projects

Biological motion (BM) analysis and interpretation is a fundamental process of human neurocognition that has been only minimally explored neurophysiologically. In addition to its importance in understanding the underlying roots and development of social cognition, BM processing is a prime candidate domain for exploring the underlying etiology of social cognitive disorders such as the autism spectrum.

In an initial experiment, typical adults observed BM point-light displays of a human actor (UM) as well as their spatially scrambled counterparts (SM), in both an unattended distractor task as well as an explicit attention task. Results showed a neurophysiological response manifested as three …

Optimizing The Analysis Of Electroencephalographic Data By Dynamic Graphs, Mehrsasadat Golestaneh

Electronic Thesis and Dissertation Repository

The brain’s underlying functional connectivity has been recently studied using tools offered by graph theory and network theory. Although the primary research focus in this area has so far been mostly on static graphs, the complex and dynamic nature of the brain’s underlying mechanism has initiated the usage of dynamic graphs, providing groundwork for time sensi- tive and finer investigations. Studying the topological reconfiguration of these dynamic graphs is done by exploiting a pool of graph metrics, which describe the network’s characteristics at different scales. However, considering the vast amount of data generated by neuroimaging tools, heavy computation load and …

Time, Perspectives, Verbs, And Imagining Events, Jeffrey P. Hong

Theses and Dissertations (Comprehensive)

During the processing of verbs, readers form internal representations of the events described by those verbs. Two key elements in the construction of event representations are temporal information, given by the verbs that describe the represented events, and the visual perspective from which the events are represented. The current study is composed of two experiments aimed at examining the roles these two factors play in event representation. Specifically, the study aimed to determine how temporal information and visual perspective are represented during event imagination.

Experiment 1 investigated the role of temporal information associated with verbs, given by grammatical aspect (GA) …

A P300 Based Cognitive Assessment Battery For Severely Motor-Impaired And Overtly Non-Responsive Patients, Aaron M. Kirschner

Electronic Thesis and Dissertation Repository

Diagnosing disorders of consciousness (DOC) is notoriously difficult, with estimates of misdiagnosis rates as high as 40%. Moreover, recent studies have demonstrated that patients who do not show signs of volitional motor responses can exhibit preserved command following detected by functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). Although these patients clearly retain some cognitive abilities, lack of consistent motor responses makes administration of standard neuropsychological tests impossible. Consequently, the extent of their cognitive function is unknown. In the current study, we developed and validated a P300b event related potential (ERP) neuropsychological battery in healthy participants to assess components of …

Low Cost Neurochairs, Frankie Pike

Master's Theses

Electroencephalography (EEG) was formerly confined to clinical and research settings with the necessary hardware costing thousands of dollars. In the last five years a number of companies have produced simple electroencephalograms, priced below $300 and available direct to consumers. These have stirred the imaginations of enthusiasts and brought the prospects of "thought-controlled" devices ever closer to reality. While these new devices were largely targeted at video games and toys, active research on enabling people suffering from debilitating diseases to control wheelchairs was being pursued. A number of neurochairs have come to fruition offering a truly hands-free mobility solution, but whether …

Gender And Color Specific Differences In Event Related Potentials, Abhishek Trikha

Theses and Dissertations

This project analyzed gender and color-specific differences in event-related potentials (ERPs). Previous studies have shown that males process color differently than females. In a recent study, sex differences were found in ERPs during a visual object recognition task. There were higher EEG amplitudes in females (especially P300) than males. Significant sex and color-specific differences have been found in diseases involving altered dopamine (DA) machinery. Thus, we analyzed differences between ERPs in males vs females during a color task. We also compared the color-specific differences in ERPs between males and females. Males and females participated in EEG recording sessions for 2 …