Neuroscience and Neurobiology Commons^™

The Temporal Nature Of The Acute Stress Response And Its Impact On Explicit Learning, Steven B. Hutchinson

Electronic Theses and Dissertations

Acute stress is commonly experienced by many throughout their lives. Given the demanding lifestyle of many career paths, it's important to gauge the influence of these stressors upon cognitive performance. The present dissertation focus' upon explicit learning in attempts to explore one avenue of the stress-cognition relationship. The Trier Social Stress Test (TSST) was used as a lab stressor for Experiments 1 and 2, in which participants are asked to give a speech and complete a difficult math task in front of 2 evaluators trained to monitor non-verbal behavior. Experiment 1 investigates the dynamic stress response during the minutes following …

Exploring And Training Spatial Reasoning Via Eye Movements: Implications On Performance, Victoria A. Roach

Electronic Thesis and Dissertation Repository

This dissertation sought to determine if eye movements could serve as an indicator of success in spatial reasoning, and if eye movements associated with successful completion could be applied to strategically improve spatial reasoning.

Using the line images of Shepard and Metzler, an electronic test of mental rotations ability (EMRT) was designed. Two versions of the test were created, allowing for both a timed (6 seconds per question) and untimed testing environment. Four experiments were designed and completed to relate mental rotation ability (MRA) scores from the EMRT, to patterns in chrononumeric and visual salience data. In each experiment, participants …

Functionally Distinct Pools Of Calcineurin Contribute To Depotentiation-Like Synaptic Changes In The Lateral Amygdala During Auditory Fear Extinction, Elena Kay Rotondo

Theses and Dissertations

Until recently, auditory fear extinction was not thought to modify substrates involved in the storage of the original auditory fear memory. Evidence now suggests that extinction results in the reversal of the fear conditioning-induced potentiation of thalamic inputs to the lateral amygdala. However, little is known about the molecular mechanisms that support this depotentiation of synaptic strength. Here we present behavioral and molecular evidence in support of the contribution of two distinct pools of the protein phosphatase calcineurin to depotentiation-like changes in lateral amygdala AMPA receptor trafficking during auditory fear extinction. Calcineurin protein that exists prior to the onset of …

Behavioral And Neural Mechanisms Of Impulsive Choice, Jesse Mcclure

Doctoral Dissertations

Impulsive choice is defined as the preference for a small immediate reward over a larger delayed reward. Individual variablity in impulsive choice correlates with many socially relevant behaviors. Although forms of impulsive choice have been studied in both behavioral ecology and psychology, the exchange of knowledge between these fields is just beginning. Drawing from both of these fields will improve our research methods allowing for a more detailed understanding of this complex behavior. Existing tasks to measure impulsive choice conflate the delay and quantity of the reward. To address this, I have drawn from foraging research to establish a method …

Suppression Of Locomotor Activity In Female C57bl/6j Mice Treated With Interleukin-1Β: Investigating A Method For The Study Of Fatigue In Laboratory Animals, David R. Bonsall, Hyunji Kim, Awa Ndiaye, Abbey Petronzio, Grace Mckay-Corkum, Penny C. Molyneux, Thomas E. Scammell, Mary E. Harrington

Psychology: Faculty Publications

Fatigue is a disabling symptom in patients with multiple sclerosis and Parkinson’s Disease, and is also common in patients with traumatic brain injury, cancer, and inflammatory disor- ders. Little is known about the neurobiology of fatigue, in part due to the lack of an approach to induce fatigue in laboratory animals. Fatigue is a common response to systemic challenge by pathogens, a response in part mediated through action of the pro-inflammatory cytokine interleukin-1 beta (IL-1β). We investigated the behavioral responses of mice to IL-1β. Female C57Bl/6J mice of 3 ages were administered IL-1β at various doses i.p. Interleukin-1β reduced locomotor …

The Neuroscience Of Attachment Theory, Sarah M. Leitner

Sarah M Leitner

This presentation summarizes the latest findings from Cognitive Neuroscience as pertains to Attachment theory, with an emphasis on the literature from 2012 to 2014. It then explores the linkages in the neuroscience literature between attachment theory and mentalization, particularly in the areas of cognitive and emotional mentalization. Implications of the findings are considered, with an emphasis on the application of the findings for emotional regulation in the life of the counselor as well as for psychological and spiritual intervention in the lives of the counselee.

One Giant Leap For Categorizers: One Small Step For Categorization Theory, David J. Smith, Shawn W. Ell

Psychology Faculty Scholarship

We explore humans’ rule-based category learning using analytic approaches that highlight their psychological transitions during learning. These approaches confirm that humans show qualitatively sudden psychological transitions during rule learning. These transitions contribute to the theoretical literature contrasting single vs. multiple category-learning systems, because they seem to reveal a distinctive learning process of explicit rule discovery. A complete psychology of categorization must describe this learning process, too. Yet extensive formal-modeling analyses confirm that a wide range of current (gradient-descent) models cannot reproduce these transitions, including influential rule-based models (e.g., COVIS) and exemplar models (e.g., ALCOVE). It is an important theoretical conclusion …

Neural And Behavioural Responses To Rewards And Losses In Early Development: A Functional Magnetic Resonance Imaging Study, Niki Hosseini-Kamkar

Electronic Thesis and Dissertation Repository

Functional magnetic resonance imaging (fMRI) was used to investigate the neural and behavioural correlates of learning from rewards and losses in children. Greater blood-oxygen-level dependent (BOLD) responses in the ventral striatum (VS) and the ventromedial prefrontal cortex (VMPFC) were found when participants received rewards compared to when they missed out on an opportunity to receive rewards. In contrast, greater BOLD responses in the anterior insula (AI) and the anterior cingulate cortex (ACC) were found when participants received losses compared to when they avoided losing. The BOLD response to rewards in the VS and VMPFC correlated positively with the tendency to …

Estrogen-Sensitive Learning Is Not Affected By Combination Ethinyl Estradiol And Levonorgestrel Oral Contraceptive Use, Darlene F. Ficco

Doctoral Dissertations

Two studies were conducted to explore the cognitive effects of combination ethinyl estradiol and levonorgestrel contraceptive use during late adolescence and young adulthood. Three groups of females, naturally cycling, active pill phase, and hormone-free interval phase, were tested on a battery of estrogen-sensitive, i.e., place learning and word generation, and estrogen-insensitive, i.e., map drawing, mental rotation, digit span, story recall, and object recall, tasks. Study 2 was conducted as a means to replicate the findings observed in Study 1 and to manipulate task difficulty and sensitivity. Two measures of mood were administered, and salivary estradiol levels at time of testing …

Relationships Between Age And White Matter Integrity In Children With Phenylketonuria, Erika M. Wesonga

Arts & Sciences Electronic Theses and Dissertations

Objective: Phenylketonuria (PKU) is a hereditary metabolic disorder associated with cognitive compromise. Diffusion tensor imaging (DTI) has allowed detection of poorer microstructural white matter integrity in children with PKU, with decreased mean diffusivity (MD) in comparison with healthy children. However, very little research has been conducted to examine the trajectory of white matter development in this population. The present study investigated potential differences in the developmental trajectory of MD between children with early- and continuously-treated PKU and healthy children across a range of brain regions.

Methods: Children with PKU (n = 31, mean age = 12.2 years) were …

The Concept Of Qailulah (Midday Napping) From Neuroscientific And Islamic Perspectives, Mohd Amzari Tumiran

Mohd Amzari Tumiran

Napping/siesta during the day is a phenomenon which is widely practised in the world. However, the timing, frequency and duration may vary. The basis of napping is also diverse, but it is mainly done for improvement of alertness and general well-being. Neuroscience reveals that midday napping improves memory, enhances alertness, boosts wakefulness and performance, and recovers certain qualities of lost night sleep. Interestingly, Islam, the religion of the Muslims, advocates midday napping primarily because it was a practice preferred by Prophet Muhammad (pbuh). The objectives of this review are to investigate and compare identical key points on focused topic from …

Responses Of Primate Frontal Cortex Neurons During Natural Vocal Communication, Cory T. Miller, A. Wren Thomas, Samuel U. Nummela, Lisa A. De La Mothe

Psychology Faculty Research

The role of primate frontal cortex in vocal communication and its significance in language evolution have a controversial history. While evidence indicates that vocalization processing occurs in ventrolateral prefrontal cortex neurons, vocal-motor activity has been conjectured to be primarily subcortical and suggestive of a distinctly different neural architecture from humans. Direct evidence of neural activity during natural vocal communication is limited, as previous studies were performed in chair-restrained animals. Here we recorded the activity of single neurons across multiple regions of prefrontal and premotor cortex while freely moving marmosets engaged in a natural vocal behavior known as antiphonal calling. Our …

Relationship Between Learning-Related Synaptic And Intrinsic Plasticity Within Lateral Amygdala, Megha Sehgal

Theses and Dissertations

A central question in neuroscience is to determine the mechanisms that govern formation, storage and modulation of memories. Determining these mechanisms would allow us to facilitate new memory formation as in the case of aging-related cognitive decline or weaken preexisting pathological memories such as traumatic memories and cue-induced drug craving. Pharmacological and genetic manipulation of intrinsic neuronal excitability has been demonstrated to impact the strength of memory formation, allocation of memories, and modulation of memories through retrieval and reconsolidation-dependent processes. In addition to experimental manipulations of intrinsic excitability, intrinsic plasticity, a change in neuronal intrinsic excitability, can be brought about …

An Analysis Of The Interaction Of Methylphenidate And Nicotine In Adolescent Rats: Effects On Bdnf, Elizabeth D. Freeman

Electronic Theses and Dissertations

This investigation was an analysis of the interaction of adolescent exposure to methylphenidate (MPH; trade name: Ritalin) on nicotine sensitization and conditioned place preference (CPP) in a rodent model and underlying mechanisms of this effect. Animals were treated IP with 1 mg/kg MPH or saline using a ―school day‖ regimen of five days on, two days off, from postnatal day (P) 28-50. During the final two weeks of MPH treatment, animals were either behaviorally sensitized to nicotine (0.5 mg/kg free base) or saline for 10 days, or conditioned to nicotine or saline using the CPP behavioral paradigm. In addition, three …

The Effect Of Sleep On Perceptual Learning And Memory Consolidation, Vanessa Claire Irsik

UNLV Theses, Dissertations, Professional Papers, and Capstones

An ability to segregate speech accurately is essential given that most auditory environments contain other overlapping conversations or environmental noise. While perceiving speech among background noise can be difficult in and of itself, those with hearing impairments can experience considerable difficulty. While training has been shown to benefit perceptual segregation of trained sounds, it is unclear how such training transfers to sounds not included in a training regimen. The current study aimed to address this question by training listeners on a portion of sounds during a vowel segregation task, and subsequently testing on both the trained sounds and untrained sounds. …

Impaired Executive Function In Concussed Athletes, Marisa Gretz

Neuroscience Summer Fellows

Concussions are classified as mild traumatic brain injuries (mTBI). An individual that has sustained a concussion will experience symptoms such as nausea, possible memory loss, blurry vision, or loss of balance. Most symptoms subside within a few days, but a large pool of research raises concern for the recovery of executive function, specifically impulse control. Executive function relates to all tasks that require deliberate attention. Past research has shown adolescents record the highest number of sports concussions when compared to collegiate and professional athletes. The frontal lobe, which controls executive function, is not fully developed during the time of adolescence. …

Senile Dementia From Neuroscientific And Islamic Perspectives, Mohd Amzari Tumiran

Mohd Amzari Tumiran

Diseases involving the nervous system drastically change lives of victims and commonly increase dependency on others. This paper focuses on Senile Dementia (SD) from both the neuroscientific and Islamic perspectives, with special emphasis on the integration of ideas between the two different disciplines. This would enable effective implementation of strategies to address issues involving this disease across different cultures, especially among the world-wide Muslim communities. In addition, certain incongruence ideas on similar issues can be understood better. The former perspective is molded according to conventional modern science while the latter on the analysis of various texts including the holy Qur’an, …

Neonatal Isolation Stress Inhibits Pre-Weaning Weight Gain And Mild-Stressor Induced Locomotor Activity In Early Adolescent Male And Female Rats, Peter Villavecchia, Mindy Miserendino

Psychology Faculty Publications

The present study looked at the effects of neonatal isolation, an early life stress experience, in male and female early adolescent rats, an age which is underrepresented in the early stress literature. Four stress-sensitive indices were assessed: weight gain during the pre-weaning period, open field activity, and locomotor activity in response to two mild stressors: exposure to a novel environment, and a single IP saline injection. Rats in the neonatal isolation condition were removed from dam and littermates on postnatal days 2-9 in accord with the procedure used by Kehoe et al. (1995); behavioral testing occurred on PN25-PN30 during …

The Effects Of Sleep-Dependent Memory Consolidation On The Discriminability And Generalizability Of Learning, Bengt Grua, Dr. C Brock Kirwan

Journal of Undergraduate Research

The goal of this study was to determine how sleep affects memory recall in an academic setting with relation to memory discrimination and memory generalization. Memory generalization depends on the computational process of pattern completion, which is the brain’s ability to retrieve a memory representation based on a partial or modified stimulus (such as viewing a false statement as true if it has many true elements embedded in it). Memory discrimination depends on the computational process of pattern separation, which is the brain’s ability to store a memory as distinct and separate from other, similar memories. Current models of sleep …

The Effect Of Exercise On Inhibitory Control To Images Of High And Low Calorie Food, Cory Pettit, Michael J. Larson, Phd

Journal of Undergraduate Research

The purpose of this study was to examine the effects of exercise on the neural correlates of response inhibition to high and low calorie foods. Specifically, we aimed to explore whether engaging in forty-five minutes of moderate intensity exercise affects brain activity that denotes inhibitory control while a person withholds practiced responses to pictures of high or low calorie food. We quantified inhibitory control by measuring the amplitude of the N2 event related potential (ERP; described below) using electroencephalogram (EEG) technology.

Social Habituation And Dishabituation In Cd-1 Mice Treated With The Norepinephrine Neurotoxin N-(2-Chloroethyl)-N-Ethyl-2-Bromobenzylamine (Dsp-4), Hewlet Mcfarlane

Hewlet McFarlane

Male CD-1 mice between postnatal days 60 and 90 were injected intraperitoneally (i.p) with either water vehicle (controls) or 50$\mu$g/g of the norepinephrine neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4). They were tested 3 to 6 days later on the odors of adult males in a four-trial habituation/dishabituation paradigm. There were four groups: group CSS were water injected and exposed to the same male on all four trials; group CSN were water injected and exposed to the same male on the first three trials and a novel one on the fourth; group DSN were DSP-4 treated and exposed the same male on the first …

Probabilistic Atlases For Face And Biological Motion Perception: An Analysis Of Their Reliability And Overlap, Andrew Engell

Andrew Engell

Neuroimaging research has identified several category-selective regions in visual cortex that respond most strongly when viewing an exemplar image from a preferred category, such as faces. Recent studies, however, have suggested a more complex pattern of activation that has been heretofore unrecognized, e.g., the presence of additional patches of activation to faces beyond the well-studied fusiform face area, and the activation of ostensible face selective regions by animate motion of non-biological forms. Here, we characterize the spatial pattern of brain activity evoked by viewing faces or biological motion in large fMRI samples (N > 120). We create probabilistic atlases for both …

Common Neural Mechanisms For The Evaluation Of Facial Trustworthiness And Emotional Expressions As Revealed By Behavioral Adaptation, Andrew Engell

Andrew Engell

People rapidly and automatically evaluate faces along many social dimensions. Here,we focus on judgments of trustworthiness, which approximate basic valence evaluation of faces, and test whether these judgments are an overgeneralization of the perception of emotional expressions. We used a behavioral adaptation paradigm to investigate whether the previously noted perceptual similarities between trustworthiness and emotional expressions of anger and happiness extend to their underlying neural representations. We found that adapting to angry or happy facial expressions causes trustworthiness evaluations of subsequently rated neutral faces to increase or decrease, respectively. Further, we found no such modulation of trustworthiness evaluations after participants …

Differential Activation Of Frontoparietal Attention Networks By Social And Symbolic Spatial Cues, Andrew Engell

Andrew Engell

Perception of both gaze-direction and symbolic directional cues (e.g. arrows) orient an observer’s attention toward the indicated location. It is unclear, however, whether these similar behavioral effects are examples of the same attentional phenomenon and, therefore, subserved by the same neural substrate. It has been proposed that gaze, given its evolutionary significance, constitutes a ‘special’ category of spatial cue. As such, it is predicted that the neural systems supporting spatial reorienting will be different for gaze than for non-biological symbols. We tested this prediction using functional magnetic resonance imaging to measure the brain’s response during target localization in which laterally …

The Fmri Bold Signal Tracks Electrophysiological Spectral Perturbations, Not Event-Related Potentials., Andrew Engell

Andrew Engell

Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) are primary tools of the psychological neurosciences. It is therefore important to understand the relationship between hemodynamic and electrophysiological responses. An early study by Huettel and colleagues found that the coupling of fMRI blood-oxygen-level-dependent signal (BOLD) and subdurally-recorded signal-averaged event-related potentials (ERPs) was not consistent across brain regions. Instead, a growing body of evidence now indicates that hemodynamic changes measured by fMRI reflect non-phase-locked changes in high frequency power rather than the phase-locked ERP. Here, we revisit the data from Huettel and colleagues and measure event-related spectral perturbations (ERSPs) to examine the …

Face, Eye, And Body Selective Responses In Fusiform Gyrus And Adjacent Cortex: An Intracranial Eeg Study., Andrew D. Engell, Gregory Mccarthy

Andrew D. Engell

unctional MRI (fMRI) studies have investigated the degree to which processing of whole faces, face-parts, and bodies are differentially localized within the fusiform gyrus and adjacent ventral occipitotemporal cortex. While some studies have emphasized the spatial differentiation of processing into discrete areas, others have emphasized the overlap of processing and the importance of distributed patterns of activity. Intracranial EEG (iEEG) recorded from subdural electrodes provides excellent temporal and spatial resolution of local neural activity, and thus provides an alternative method to fMRI for studying differences and commonalities in face and body processing. In this study we recorded iEEG from 12 …

Selective Attention Modulates Face-Specific Induced Gamma Oscillations Recorded From Ventral Occipitotemporal Cortex, Andrew Engell

Andrew Engell

EEG studies from subdural electrodes have demonstrated a face-specific event-related potential (face-N200) recorded from human ventral occipitotemporal cortex. The insensitivity of face-N200 to task manipulations has supported the proposal that face-N200 reflects an initial obligatory response to faces. This result stands in striking contrast to results of neuroimaging studies that have demonstrated strong task sensitivity of the fusiform hemodynamic response evoked by faces, and thus has created a paradox in the face perception literature. We recorded field potentials directly from the cortical surface of 16 patients while they selectively attended to faces or houses. Here we report that face-specific gamma …

Facial Expression And Gaze-Direction In Human Superior Temporal Sulcus, Andrew Engell

Andrew Engell

The perception of facial expression and gaze-direction are important aspects of non-verbal communication. Expressions communicate the internal emotional state of others while gaze-direction offers clues to their attentional focus and future intentions. Cortical regions in the superior temporal sulcus(STS) play a central role in the perception of expression and gaze, but the extent to which the neural representations of these facial gestures are overlapping is unknown. In the current study 12 subjects observed neutral faces with direct-gaze, neutral faces with averted-gaze, or emotionally expressive faces with direct-gaze while we scanned their brains with functional magnetic resonance imaging (fMRI), allowing a …

Implicit Trustworthiness Decisions: Automatic Coding Of Face Properties In Human Amygdala, Andrew Engell

Andrew Engell

Deciding whether an unfamiliar person is trustworthy is one of the most important decisions in social environments. We used functional magnetic resonance imaging to show that the amygdala is involved in implicit evaluations of trustworthiness of faces, consistent with prior findings. The amygdala response increased as perceived trustworthiness decreased in a task that did not demand person evaluation. More importantly, we tested whether this response is due to an individual’s idiosyncratic perception or to face properties that are perceived as untrustworthy across individuals. The amygdala response was better predicted by consensus ratings of trustworthiness than by an individual’s own judgments. …

A Kinematic Analysis Of Visual And Haptic Contributions To Precision Grasping In A Patient With Visual Form Agnosia And In Normally-Sighted Populations, Robert Whitwell

Electronic Thesis and Dissertation Repository

Skilled arm and hand movments designed to obtain and manipulate objects (prehension) is one of the defining features of primates. According to the two visual system hypothesis (TVSH) vision can be parsed into two systems: (1) the ventral ‘stream’ of the occipital and inferotemporal cortex which services visual perception and other cognitive functions and (2) the ‘dorsal stream’ of the occipital and posterior parietal cortex which services skilled, goal-directed actions such as prehension. A cornerstone of the TVSH is the ‘perception-action’ dissociation observed in patient DF who suffers from visual form agnosia following bilateral damage to her ventral stream. DF …