Medicine and Health Sciences Commons^™

Possible Breakdown Of Dopamine Receptor Synergism In A Mouse Model Of Huntington's Disease, Samantha F. Kennedy

University of New Orleans Theses and Dissertations

The model of basal ganglia function proposed by Albin, Young and Penney (1989) describes two anatomically independent motor pathways, the direct and indirect. However, under normal conditions striatal dopamine (DA) is required for the expression of motor behavior, and DAergic control of the two pathways (via D1 and D2 receptors, respectively) is dependent on co-activation. We tested for a possible breakdown of D1/D2 synergism using transgenic R6/1 mice bearing the human huntingtin allele (Htt). Motor stereotypy, observed prior to the onset of HD-related symptoms, was rated on a 5-point scale following activation of: A) D1 receptors alone, B) D2 receptors …

Neurocorrelates Of The Mirror Neuron System In Children With Chromosome 22q11.2 Deletion Syndrome, Ade Marais

University of New Orleans Theses and Dissertations

Activation of brain regions that make up the mirror neuron system (MNS) is thought to reflect processing and perceiving behavior, action, and intentionality of other organisms. Sensing and perceiving motor behavior in others is an important component of understanding and participating in social interactions. Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) are diagnosed with serious medical, cognitive, and socio-emotional symptoms. Atypical development and function of the MNS may underpin some aspects of socio-emotional impairment and autism spectrum disorder (ASD)-like symptomology reported. This study of the MNS investigates differences in activation in the operculum, sensorimotor areas, and basal ganglia (BG) in …

Contributions Of Appetitive And Aversive Motivational Systems To Decision-Making, Heather E. Soder

USF Tampa Graduate Theses and Dissertations

Optimal decision-making entails outcome evaluation, comparing received costs and benefits with predicted costs and benefits. The anterior cingulate cortex (ACC), a brain area with major connections to the appetitive and aversive motivation systems, may provide the neural substrate of this evaluation process. One way to measure the relative contribution of these systems on decision-making is to measure individual differences in risk-taking behaviors. For individuals who make risky choices, this evaluation step may be biased: some show a preference for immediate, short-term rewards (increased appetitive system), while devaluing the long-term consequences of their choices (decreased aversive system). However, most studies supporting …

Volition And Action In The Human Brain: Processes, Pathologies, And Reasons, Itzhak Fried, Patrick Haggard, Biyu J. He, Aaron Schurger

Psychology Faculty Articles and Research

Humans seem to decide for themselves what to do, and when to do it. This distinctive capacity may emerge from an ability, shared with other animals, to make decisions for action that are related to future goals, or at least free from the constraints of immediate environmental inputs. Studying such volitional acts proves a major challenge for neuroscience. This review highlights key mechanisms in the generation of voluntary, as opposed to stimulus-driven actions, and highlights three issues. The first part focuses on the apparent spontaneity of voluntary action. The second part focuses on one of the most distinctive, but elusive, …

The Effects Of Sports Related Head Impact On Balance And Neurocognitive Functions, Shaquanda D. Ross-Simmons, Michelle L. Vieyra, Abhishek Jain, Keri Weed

Journal of the South Carolina Academy of Science

The goal of this study was to investigate the effects of sports-related head injury on balance, attention, and memory. Reliable differences have been found using measures that directly tap into brain functioning, such as the auditory oddball task combined with EEG recording. We hypothesized that athletes reporting a diagnosed concussion or participation in high-risk sports would have compromised balance and neurocognitive functioning compared to athletes in low risk sports. Forty-five undergraduate participants were identified as either concussed, non-concussed in high-risk sports, or non-concussed in low-risk sports using a survey of athletic history, head trauma and demographics. The Biopac MP36 system, …

Entrainment Of Voluntary Movement To Undetected Auditory Regularities, Aaron Schurger, Nathan Faivre, Leila Cammoun, Bianca Trovó, Olaf Blanke

Psychology Faculty Articles and Research

In physics “entrainment” refers to the synchronization of two coupled oscillators with similar fundamental frequencies. In behavioral science, entrainment refers to the tendency of humans to synchronize their movements with rhythmic stimuli. Here, we asked whether human subjects performing a tapping task would entrain their tapping to an undetected auditory rhythm surreptitiously introduced in the guise of ambient background noise in the room. Subjects performed two different tasks, one in which they tapped their finger at a steady rate of their own choosing and one in which they performed a single abrupt finger tap on each trial after a delay …

Roles Of Gabab, Muscarinic And Nicotinic Receptor Signaling In The Acquisition And Expression Of Fructose And Fat-Conditioned Flavor Preferences And Acquisition Of Quinine-Conditioned Flavor Avoidances In Rats, Francis M. Rotella

Dissertations, Theses, and Capstone Projects

In addition to increased intake of sweet solutions by mammals, learning, particularly classically-conditioned “Pavlovian-like” learning, also plays an important role. An orosensory conditioned flavor preference (CFP) can be elicited by pairing one novel flavor (conditioned stimulus, CS+) with a fructose solution and a second novel flavor (CS-) with a saccharin solution. Rats will prefer the CS+ flavor in a subsequent 2-bottle choice test with both flavors mixed in saccharin. Previous pharmacological analyses revealed that systemic administration of dopamine (DA) D1 and D2 as well as NMDA, but not opioid, receptor antagonists eliminated the acquisition (learning) of fructose-CFP. Further, expression of …

Rumination Is Associated With Diminished Performance Monitoring, Ema Tanovic, Greg Hajack, Charles A. Sanislow

Charles A. Sanislow, Ph.D.

A Diffusion Tensor Imaging Study Of Motor Fibre Path Integrity And Overt Responsiveness In Disorders Of Consciousness, Clara A. Stafford

Electronic Thesis and Dissertation Repository

This study investigated the relationship between motor thalamo-cortico-cerebellar fibre path integrity and overt responsiveness in patients with disorders of consciousness (DOC). Additionally, we investigated the potential of imaging these motor tracts at ultra-high fields. Study I and II aimed to map the white matter connections of motor execution fibres in DOC patients. Our results showed significant reductions in motor fibre path integrity across DOC diagnostic categories. Study III and IV aimed to develop a 7T MRI Diffusion Tensor Imaging (DTI) sequence. We optimized this sequence to image motor fibre paths in DOC patients. We concluded that, in healthy controls, probabilistic …

Cumulative Trauma, Emotion Reactivity And Salivary Cytokine Response Following Acute Stress Among Healthy Women., Yvette Z. Szabo

Electronic Theses and Dissertations

This study furthers understanding of how trauma exposure may be connected to the development and maintenance of poor health by focusing on cytokines, tightly regulated proteins of the immune system. Cytokine responses to acute stress have been associated with the onset of poorer mental health in physically healthy women. The present study examined how two factors recently associated with cytokine reactivity –cumulative trauma and emotion reactivity– are associated with salivary cytokine reactivity among healthy women. Seventy-one women, screened to be physically and mentally healthy, completed a laboratory acute stress paradigm and self-report measures of state emotion and trauma exposure. Participants …

The Relationship Of Early Class Start Times On Sleepiness And Driving Behaviors In An Emerging Adult Population, Jessica L. Fry

Psychology Theses & Dissertations

Teenage driver sleepiness is a recent concern for preventing motor vehicle fatalities. Early school start times limit the amount of sleep teenage high school students acquire during the week and have been related to increased crash risk. The current study extends this finding to teenage and emerging adult college students. The author examined the link between sleepiness and teenage driving behaviors, including the relationship between school start times and sleepiness. In all, 536 participants were recruited to participate in an online survey assessing driving and sleep behaviors. Correlations and path analysis found that sleepiness fully mediated the relationship between early …

An Analysis Of Neurogenesis In A Mouse Model Of Chemotherapy Related Cognitive Impairment, Maxwell A. Hennings

Electronic Theses and Dissertations

Cancer patients treated with adjuvant chemotherapy often experience cognitive decline following treatment. This phenomenon, often dubbed “chemo brain” or “chemo fog” is usually temporary, but for a subset of survivors, these cognitive impairments can be long-lasting (>10 years) and negatively affect patients’ quality of life, career performance, and social fulfillment. While it is unclear what neurobiological mechanisms underlie chemotherapy related cognitive impairment, the majority of the animal literature has focused on adult neurogenesis. One process important for neurogenesis is the proliferation of new neurons within the dentate gyrus of the hippocampus. It is evident that many chemotherapy agents can …

Sleep Deprivation And Voluntary Alcohol Consumption In Adult Rats, Charles M. Cowan Ii

Masters Theses, 2010-2019

Alcohol is a psychoactive drug with a large userbase among adults across the globe. However, alcohol use also reduces the quality of sleep in the user. Historically, research has focused on the effects of alcohol on sleep architecture, but recent research has started to examine the effects of sleep deprivation on alcohol consumption. This research examines the effects of sleep deprivation on voluntary alcohol consumption in adult rats. Twelve Sprague Dawley rats were given ad libitum access to food, alcohol (7% solution), and water for the duration of this study. Subjects were then placed into non-moving forced exercise wheels to …

Humor In Medicine: A Literature Review Of Humor’S Potential Therapeutic Value In Health Care, Weston Michael Grant

Psychological Science Undergraduate Honors Theses

Using humor and laughter within the health care field has the potential to be relevant to patients during treatment, to the patient-caregiver relationship, to the subjective well-being of health care providers, and to the environments’ (e.g., work settings) impact on group relationships (e.g., colleagues). A review of the literature examines how the psychological and physiological effects of laughter and humor within the human body impact health and well-being, how humor and laughter improve the patient-practitioner relationship, and if humor and laughter can potentially impact physician burnout. Several possible implications for these findings are discussed, such as professional medical comedians, improvements …

The Impact Of Stress On Steroid Hormones And Cue Reactivity In Smokers And Gamblers, Stephanie Elaine Wemm

Legacy Theses & Dissertations (2009 - 2024)

Addictions, both substance and behavioral, have been conceptualized as having similar biopsychosocial processes with different opportunistic expressions (Shaffer et al., 2004). Biological processes such as the hormonal response to stress as measured by cortisol, dehydroepiandrosterone (DHEA), and the ratio of the DHEA/cortisol may be among the variables underlying the disposition to develop an addictive disorder, regardless of whether it is a substance-based or a so-called behavioral addiction. The current study aimed to examine whether physiological and psychological reactions to stress are similar in high-frequency smokers and gamblers. The subjective (urges, cravings) and physiological responses (skin conductance and heart rate) of …

The Poverty Of The Neuroscience Of Poverty: Policy Payoff Or False Promise?, Amy L. Wax

All Faculty Scholarship

A recent body of work in neuroscience examines the brains of people suffering from social and economic disadvantage. This article assesses claims that this research can help generate more effective strategies for addressing these social conditions and their effects. It concludes that the so-called neuroscience of deprivation has no unique practical payoff, and that scientists, journalists, and policy-makers should stop claiming otherwise. Because this research does not, and generally cannot, distinguish between innate versus environmental causes of brain characteristics, it cannot predict whether neurological and behavioral deficits can be addressed by reducing social deprivation. Also, knowledge of brain mechanisms yields …

Restoration Of Attentional Deficits After Concussion, Katharine B. Earle

Cal Poly Humboldt theses and projects

Difficulties with concentration and attention are among the most prevalent symptoms experienced after concussion. Rest has been the most common form of recovery from concussion; however, new research is suggesting mild mental exertion to be an effective aid in recovery. Drawing from Attention Restoration Theory, this study evaluated the idea that cognitive engagement with natural environments can mitigate post-concussion directed-attention deficits. A between subjects repeated measures design was used to test directed-attention after video exposure to restorative/nature and nonrestorative/city environments. Measures of mood, connectedness to environment, and symptomology scores were also collected. No meaningful difference between exposure type was found …

The Effect Of Two Modes Of Aerobic Assessment On Fifth Grade Students' Self Efficacy, Debra Roth

Walden Dissertations and Doctoral Studies

Declining youth physical activity levels and lack of aerobic fitness have been well documented with a corresponding rise in obesity levels and health issues. Based on Bandura's social cognitive theory, healthy physical activity levels and aerobic fitness are strongly connected to positive physical activity self-efficacy beliefs. This study examined whether student physical activity self-efficacy, motivation, and effort were different for the FitnessGram-® (FG) 1-Mile Run when compared to the 15-minute Aerobic Assessment Based on Improvement (AABI). A concurrent mixed method quasi-experimental approach measured 5th grade students' physical activity self-efficacy beliefs through a pretest and posttest survey while aerobic assessment scores …