Neuroscience and Neurobiology Commons^™

An Eeg Study On Loneliness And Recognition Memory, Carmen Jia Wen Chek

Electronic Theses and Dissertations

Loneliness, the perception of unmet social needs, has been shown to relate to recollection-based recognition deficits, but the relationship between loneliness and recognition memory (i.e., recollection and familiarity) has not been thoroughly examined. The current study hypothesized that more lonely individuals would have lower recognition memory performance, specifically recollection, with smaller ERP parietal old-new effects than less lonely individuals. Forty participants, grouped into less (n = 13) and more (n = 9) lonely groups based on their R-UCLA responses, completed an associative memory task. EEG was used to assess recognition memory effects. Results showed no significant difference in …

Working Memory And Attention Deficits During A Letter Number Sequencing Task Post-Concussion, Shannon Kiss

Neuroscience Honors Papers

As the prevalence of sports related concussions rise, the long-term effects of concussions have garnered increasing research attention. Previous research has demonstrated that certain dimensions of executive function are especially susceptible to mild traumatic brain injury (mTBI), specifically working memory and attention. Previous studies using EEG have found that increased very low frequency oscillations (VLFO) disrupt goal-oriented activities and are associated with difficulties in cognition, hyperactivity and inattention in concussed individuals after mTBI. This study utilized continuous EEG during a letter number sequencing task on concussed and non-concussed individuals to assess deficits related to working memory and attention. It was …

The Action-Perception Of Musical Rhythm: A Review Of Eeg Findings, Jordan Anderson

Summer Research

Electroencephalography (EEG) research has the potential to illuminate questions of connectivity and temporal dynamics during musical rhythm perception. The phenomenon of sensorimotor synchronization observed when humans time their movements to rhythmic auditory stimuli reveals that these actions predict, rather than respond, to the beat. The phase entrainment of oscillatory activity measured by EEG and predictive modulation of beta band power offer cognitive insights to the auditory-motor relationship. Two main approaches exist to understand beat perception: motor simulation theories and dynamical systems theories. The study of mu wave suppression, considered a marker for mirror activity, has the potential to elucidate the …

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 …

Artificially-Generated Scenes Demonstrate The Importance Of Global Properties During Early Scene Perception, Mavuso Wesley Mzozoyana

Browse all Theses and Dissertations

During scene perception, studies have shown the importance of the global distribution of a scene. Electrophysiological studies have found these global effects concentrated corresponding to the second positive and first negative peaks (P2 and N1, respectively) of the Event-related potential (ERP) during the first 600 ms of scene perception. We sought to understand in Experiment 1, to what extent early responses to scenes were driven by mid-level global information such as the degree of naturalness or openness in a scene image in the absence of specific low-and high-level information (color and semantic object detail). This was done using artificially-generated stimuli …

Visual Modulation Of Resting State Α Oscillations, Kelly Webster, Tony Ro

Publications and Research

Once thought to simply reflect passive cortical idling, recent studies have demonstrated that α oscillations play a causal role in cognition and perception. However, whether and how cognitive or sensory processes modulate various components of the α rhythm is poorly understood. Sensory input and resting states were manipulated in human subjects while electroencephalography (EEG) activity was recorded in three conditions: eyes-open fixating on a visual stimulus, eyes-open without visual input (darkness), and eyes-closed without visual input (darkness). We show that α power and peak frequency increase when visual input is reduced compared to the eyes open, fixating condition. These results …

The Influence Of Neural Reward Processing On Memory In Depression, Nathan M. Hager

Psychology Theses & Dissertations

Theories and research suggest that depression involves impaired reward sensitivity and a deficit in memory for rewarding stimuli. Some researchers propose that this memory deficit may result from reduced neural reward sensitivity, which impairs the encoding of reward-related memories, but few studies have directly probed this connection. Such research may benefit from examining the reward positivity (RewP), an event-related potential (ERP) previously linked to reduced reward sensitivity in depression. Undergraduates with high or low self-reported depression completed a task in which they chose one of three doors, revealing a neutral word written in a color which indicated an outcome of …

The Role Of Gamma Oscillations And Cortical Inhibition In The Development Of Working Memory In Adolescence, Christopher P. Walker

Dissertations & Theses (Open Access)

Adolescence is a dynamic period of social, cognitive, and biological changes. In particular, working memory, the ability to actively encode and maintain information over a short period of time, develops early in childhood and gradually increases in capacity and stability during adolescence. The precise neurophysiological mechanism by which working memory capacity increases during adolescence is unclear. The objective of this investigation was to evaluate the role of cortical gamma-band (> 30 Hz) oscillations—which are associated with working memory in adults—for the development of working memory capacity in adolescents, and to identify the extent to which the temporal profile of gamma-aminobutyric …

Visual Entrainment Of Perception-Related Neural Oscillations As A Mechanism For Maintaining Rhythmic Temporal Expectations Across A Wide Range Of Frequencies, Michael James Gray

Dissertations, Theses, and Capstone Projects

Visual sensitivity fluctuates rhythmically, in-synch with ongoing, EEG-recorded neural oscillations across a wide range of frequencies (~1-25hz). Some recent work has suggested that these perception-related neural oscillations can be entrained by rhythmic visual stimulation. Evidence is also emerging that the entrainment of ongoing oscillations in visual and auditory cortices is involved in rhythmic temporal expectations. In the introduction chapter, I attempt to bridge these bodies of literature and hypothesize that rhythmic visual stimuli automatically entrain ongoing, perception-related neural oscillations and that this mechanism supports the maintenance of rhythmic temporal expectations. Chapters 2 and 3 address this hypothesis from different angles. …

Neural Correlates Of Automatic Emotional Processing And Emotion Regulation In Empathy And Psychopathy-Related Coldheartedness, Danielle Difilipo

Dissertations, Theses, and Capstone Projects

Psychopathy is a personality disorder that is defined, in part, by a lack of empathy. Psychopathy-related empathic deficits have been associated with atypical behavioral and neural responses to emotional facial expressions. Although the mirror neuron system (MNS) has been implicated in empathy, very few studies have examined the role of MNS functioning as it pertains to empathy impairments in psychopathy. Moreover, there is very little empirical research regarding emotion regulation in psychopathy, and specifically whether emotional responses can be intentionally upregulated. The present study sought to clarify whether the MNS is functionally intact in adults with subclinical psychopathic traits, particularly …

Using Meditation To Improve Measures Of Attention In Older Adults, Sabrina Ford

Electronic Thesis and Dissertation Repository

Age-related cognitive decline greatly impacts quality of life for older adults. Previous research has indicated that meditation may act as a neuroprotective factor to prevent age-related cognitive decline. This thesis sought to replicate previous findings and investigate if a four-week meditation intervention would improve sustained attention. Participants 60 years and older (n=27, 17 female) were recruited and assigned to a focused-attention (FA) meditation or relaxation group which met for four weeks, three times a week. Resting-state EEG was used to collect individual alpha peak frequency (iAPF) and frontal alpha asymmetry (FAA). The Sustained Attention to Response Task (SART) was also …

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 Variability Of Neural Responses To Naturalistic Videos Change With Age And Sex, Agustin Petroni, Samantha Cohen, Lei Ai, Nicolas Langer, Simon Henin, Tamara Vanderwal, Michael P. Milham, Lucas C. Parra

Publications and Research

Neural development is generally marked by an increase in the efficiency and diversity of neural processes. In a large sample (n=114) of human children and adults with ages ranging from 5 to 44 yr, we investigated the neural responses to naturalistic video stimuli. Videos from both real-life classroom settings and Hollywood feature films were used to probe different aspects of attention and engagement. For all stimuli, older ages were marked by more variable neural responses. Variability was assessed by the intersubject correlation of evoked electroencephalographic responses. Young males also had less-variable responses than young females. These results were replicated in …

Maturation In Auditory Event-Related Potentials Explains Variation In Language Ability In Children., Elaine Yuen Ling Kwok, Marc F Joanisse, Lisa Archibald, Margot E. Stothers, Heather M Brown, Janis Oram Cardy

Health and Rehabilitation Sciences Publications

Processing of auditory information in the cortex continues to develop into later childhood and adolescence. Recent research has indicated that intraclass correlation (ICC) is the best method for capturing maturation in auditory event-related potentials (AEPs) of school-age children. However, the sensitivity of the ICC approach in discerning AEP changes in children has not been consistently demonstrated and positive results have not been replicated. We attempted this replication and further explored whether AEP maturation estimated using the ICC approach predicts cognitive and linguistic abilities in addition to chronological age. We measured AEPs in response to simple tones in groups of 7-, …

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 …

Effects Of Language Immersion Versus Classroom Exposure On Advanced French Learners: An Erp Study, Alexandra Claire Brito

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

University students often report making significant advances in their second language (L2) ability after immersion in a nonnative language through study abroad. The degree to which late L2 learners can become nativelike in terms of L2 performance and brain processing is unclear in second language acquisition research. The link between L2 proficiency and learning context has been characterized in previous research, yet the role of learning experience in attaining nativelike brain processing of L2 remains to be elucidated. This study contrasts learners with advanced French proficiency who have attained this level with no, little, or more immersion experience through study …

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 …

Tuning Up The Old Brain With New Tricks: Attention Training Via Neurofeedback, Yang Jiang, Reza Abiri, Xiaopeng Zhao

Sanders-Brown Center on Aging Faculty Publications

Neurofeedback (NF) is a form of biofeedback that uses real-time (RT) modulation of brain activity to enhance brain function and behavioral performance. Recent advances in Brain-Computer Interfaces (BCI) and cognitive training (CT) have provided new tools and evidence that NF improves cognitive functions, such as attention and working memory (WM), beyond what is provided by traditional CT. More published studies have demonstrated the efficacy of NF, particularly for treating attention deficit hyperactivity disorder (ADHD) in children. In contrast, there have been fewer studies done in older adults with or without cognitive impairment, with some notable exceptions. The focus of this …

Eeg Study Of The Featural And Configural Components Of Face Perception, Heather Rose Stegman

Summer Research

Prior research using functional magnetic resonance imaging (fMRI) suggests that facial features (i.e. eyes, nose, and mouth) and their configuration (i.e. T-shaped arrangement of features) are processed in different face-specific brain regions. However, precise response time of featural and configural face processing is unknown. Featural processing may occur before configural processing, or configural processing may occur before featural processing; conversely, they may occur simultaneously. Here, using the electroencephalography (EEG), we will examine the face-specific event related potential (ERP), the N170, to analyze temporal differences between featural and configural face processing.

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 …