Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

Influence Of Genetic Variation In The Biotic Environment On Phenotypic Variation In A Plant-Feeding Insect, Darren Rebar Dec 2013

Influence Of Genetic Variation In The Biotic Environment On Phenotypic Variation In A Plant-Feeding Insect, Darren Rebar

Theses and Dissertations

While many species spend much of their lives in close association with other organisms, only recently have biologists started to explore the implications of the biotic nature of environments for their role as causes of variation in phenotypes. This means that the genotypes of individuals that constitute the biotic environment may influence the phenotypes of individuals that live in that environment. These are called indirect genetic effects (IGEs) when they occur between conspecifics, and interspecific indirect genetic effects (IIGEs) when they occur between heterospecifics. However, the impact of genetic variation in biotic environments remains largely unknown. I used a member ...


The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis Dec 2013

The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis

Theses and Dissertations

A wealth of research has outlined the neural circuits responsible for the consolidation, reconsolidation, and extinction of standard "delay" fear conditioning, in which awareness is not required for learning. Far less is understood about the neural circuit supporting more complex, explicit associations. "Trace" fear conditioning is considered to be a rodent model of explicit fear because it relies on the cortex and hippocampus and requires explicit contingency awareness in humans for successful acquisition. In the current set of studies, we aimed to better characterize the neural circuit supporting the consolidation, reconsolidation, and extinction of trace fear in order to better ...


Neural Responses During Trace Conditioning With Face And Non-Face Stimuli Recorded With Magnetoencephalography, Nicholas Lee Balderston Dec 2013

Neural Responses During Trace Conditioning With Face And Non-Face Stimuli Recorded With Magnetoencephalography, Nicholas Lee Balderston

Theses and Dissertations

During fear conditioning a subject is presented with an initially innocuous stimulus like an image (conditioned stimulus; CS) that predicts an aversive outcome like a mild electric shock (unconditioned stimulus; UCS). Subjects rapidly learn that the CS predicts the UCS, and show autonomic fear responses (CRs) during the presentation of the CS. When the CS and the UCS coterminate, as is the case for delay conditioning, individuals can acquire CRs even if they are unable to predict the occurrence of the UCS. However when there is a temporal gap between the CS and the UCS, CR expression is typically dependent ...


Dissociation Of Β1 And Β2 Adrenergic Receptor Subtypes In Retrieval And Reconsolidation Of A Cocaine Conditioned Place Preference, Michael Fitzgerald Aug 2013

Dissociation Of Β1 And Β2 Adrenergic Receptor Subtypes In Retrieval And Reconsolidation Of A Cocaine Conditioned Place Preference, Michael Fitzgerald

Theses and Dissertations

Drug-seeking behavior is maintained by encounters with drug-associated cues, and disrupting retrieval or reconsolidation of the drug-cue associations could reduce the risk of relapse. Previous work has shown beta-adrenergic receptor (beta-AR) antagonists can prevent retrieval or reconsolidation of a cocaine conditioned place preference (CPP) when administered either before or after test, respectively (Otis and Mueller, 2011; Otis et al., 2013). However, the specific beta-AR subtypes that mediate retrieval and reconsolidation of a cocaine CPP remain unknown. Here we used selective blockade of & beta-1 or beta-2-AR subtypes to determine the effects on retrieval and reconsolidation of a cocaine CPP. During conditioning ...


Exercise-Induced Hypoxia, Angiogenesis, And Behavioral Flexibility In The Adult Rat, Kiersten Lee Berggren Aug 2013

Exercise-Induced Hypoxia, Angiogenesis, And Behavioral Flexibility In The Adult Rat, Kiersten Lee Berggren

Theses and Dissertations

Exercise induces a myriad of effects on the brain from the growth of new capillaries and neurons, to improvements in cognitive performance. Additionally, recent research has shown that commencement of an exercise regimen also causes apoptosis. Therefore, it is possible that exercise-induced increases in oxygen demand cause the brain to transiently experience a state of hypoxia. To investigate this hypothesis, we measured protein levels of hypoxia inducible factor 1 alpha (HIF-1α), a transcription factor known to be upregulated in conditions of hypoxia or ischemia, in animals exposed to a single bout of treadmill exercise. After exercise animals were sacrificed at ...


Alcohol Biomarkers As Predictive Factors Of Rearrest In High Risk Repeat Offense Drunk Drivers, Brian Charles Kay Aug 2013

Alcohol Biomarkers As Predictive Factors Of Rearrest In High Risk Repeat Offense Drunk Drivers, Brian Charles Kay

Theses and Dissertations

Alcohol biomarkers, or naturally occurring molecules which occur in response to one's alcohol consumption, are proving to be a value tool in objectively monitoring one's alcohol consumption. Coupling this assessment tool, with advances in computing power, new and powerful predictions are becoming evermore possible. In this retrospective study, data was first collected that consisted of a sample of 249 drivers convicted of driving under the influence charge and who monitored over the course of a year by biomarker blood tests. This data was then analyzed using machine learning methods. TwoStep cluster analysis showed distinct drinking groups within the ...


The Role Of A Camkii/Pka-Protein Degradation-Glur2 Pathway In The Control Of Memory Updating Following Retrieval, Timothy Jarome Aug 2013

The Role Of A Camkii/Pka-Protein Degradation-Glur2 Pathway In The Control Of Memory Updating Following Retrieval, Timothy Jarome

Theses and Dissertations

Reconsolidation is thought to be a process whereby consolidated memories can be modified following retrieval. However, very little is known about the molecular mechanisms that regulate this reconsolidation process. In the present series of experiments we tested if memories "destabilize" or become labile following retrieval through a specific signaling pathway. We found that retrieval of a contextual fear memory differentially increased proteasome activity in the amygdala and hippocampus and resulted in unique changes in AMPA receptor subunit expression in these brain regions. These changes were dependent on CaMKII activity, which was required for increases in Rpt6-S120 phosphorylation, proteasome activity and ...


Immediate Early Gene Expression In Medial Prefrontal Cortex And Hippocampus As A Function Of Aging, Megha Sehgal May 2013

Immediate Early Gene Expression In Medial Prefrontal Cortex And Hippocampus As A Function Of Aging, Megha Sehgal

Theses and Dissertations

Normal aging is accompanied by cognitive decline that differs from other aging-related pathological states like Alzheimer's disease. With an increasing proportion of the world population falling in an age group of 65 years and above, a preventive gerontological approach would improve the quality of life in the elderly. Especially important in this regard is the early detection of cognitive decline, so that appropriate measures can be taken to prevent development of cognitive deficits. Impairment in cognitive flexibility, the ability to modify a previously learnt behavior, is one such measure of impairment across species in aged animals. Previous work from ...


The Role Of Nmda Receptors In Extinction Of Cocaine Self-Administration, Madalyn Hafenbreidel May 2013

The Role Of Nmda Receptors In Extinction Of Cocaine Self-Administration, Madalyn Hafenbreidel

Theses and Dissertations

Relapse is highly prevalent among recovering addicts, and can be triggered by associations made between the rewarding effects of the drug and cues, such as drug paraphernalia or contexts. Inhibiting these associations, through new extinction learning, could help reduce relapse rates. Extinction is formed in phases, like other types of memory. The memory first is acquired in short-term memory, then is consolidated into long-term storage from which it can be retrieved at a later time (Quirk & Mueller, 2008). NMDA receptors are necessary for extinction in other paradigms (Santini, Muller, & Quirk, 2001), and we previously found that blocking NMDA receptors before ...


Investigation Of Web-Based Motivational Interviewing To Increase Physical Activity Participation Among Adults, Sasha Karnes May 2013

Investigation Of Web-Based Motivational Interviewing To Increase Physical Activity Participation Among Adults, Sasha Karnes

Theses and Dissertations

Interventions to enhance physical activity (PA) participation are needed given the high prevalence of under-activity and inactivity (CDC, 2001) and related occurrence of negative health consequences among the general adult population (Kung, Hoyert, Xu, & Murphy, 2008). Preliminary support for a therapeutic technique called Motivational Interviewing (MI) suggests promise for application to enhance PA participation (Burke, Arkowitz, & Menchola, 2003). Given the need for interventions to enhance PA and the preliminary support for MI as an intervention to increase PA, the aims of the current study were to: (a) determine if web-based MI is effective in enhancing PA participation, and (b) assess the mechanisms by which web-based MI enhances PA through changes in targeted cognitive variables. Participants (n= 23, under-active or inactive adults) engaged in four web-based MI sessions. Steps per day, PA, and cognitive variables were assessed across time. Efficacy of MI in enhancing PA participation was demonstrated through: (a) increases in steps per day (t[22]= 2.085, p = 0.049); (b) increases in total PA energy expenditure per week( χ2= 8.430, p = 0.015); and (c) increases in moderate intensity PA energy expenditure per week ( χ2= 13.853, p = 0.001). Although mediation of change in PA by cognitive variables was inconclusive due to sample size, changes were observed in the expected direction for cognitive variables including: (a) percentage of participants classified as action or ...


Behavior Change In Applied Sport Psychology: The Use Of Processes Of Change In Psychological Training For Athletes, William Vincent Massey May 2013

Behavior Change In Applied Sport Psychology: The Use Of Processes Of Change In Psychological Training For Athletes, William Vincent Massey

Theses and Dissertations

The results of previous research (e.g. Leffingwell, Rider, & Williams, 2001; Massey, Meyer, & Hatch, 2011; Zizzi & Perna, 2003) have led scholars to conclude that the Transtheoretical Model (TTM) may be an appropriate paradigm to study readiness to change in sport psychology settings. However, processes of change - a critical element to the TTM - have yet to be studied or measured in an athlete population. As such, the purpose of the current investigation was to initially develop and examine a measure of the processes of change for use in applied sport psychology settings. Informed by relevant literature, an initial pool of 114 items was generated. Content validity was established by consensus agreement of three judges with expertise in elite sport performance. In an effort to test the psychometric properties of the measure, data were then collected from two independent samples. Participants included National Collegiate Athletic Association Division I athletes, professional athletes, and athletes training for or competing in the Olympic Games (n1 = 201; n2 = 358). In sample one, exploratory structural equation modeling yielded a 7-factor solution (χ2 = 117.719, p = .003; CFI = .973; TLI = .942; RMSEA = .043). In sample two, a CFA was used to cross-validate the model structure found in sample one (χ2 = 372.588, p < .001; CFI = .949; TLI = .937; RMSEA = .043). Model-based reliability coefficients were calculated using standardized estimates with five of the seven subscales showing sufficient reliability (ω = 0.74 - 0.85). The Processes of Change in Sport Questionnaire (PCSQ) demonstrated concurrent validity with a modified version of the Processes of Exercise Change questionnaire (Marcus et al., 1992). Additionally, construct validity was shown as there were significant differences in the use of an athlete's processes of change across classifications of stage of change (p < .05). Results of the current study contribute to the sport performance and behavior change literature as it is the first to show validity for the processes of change construct as it relates to adopting and adhering to a PST routine for improved sport performance. While measuring the long-term effects of psychological intervention on sport performance remains a difficult task given the multitude of variables that account for sport performance, the TTM provides a framework for sport psychology professionals to address another key issue in the field - whether or not they are successful in helping athletes change and maintain more productive behaviors. As such, researchers should continue to examine whether TTM constructs can be measured reliably in an athletic population in an effort to create stage-based mental skills training interventions.


Discrimination Trials To Influence Self-Awareness, Kerin A. Weingarten May 2013

Discrimination Trials To Influence Self-Awareness, Kerin A. Weingarten

Theses and Dissertations

Humans often use terms and concepts that include self- as prefix in an effort to explain their behavior (e.g., self-awareness, self-control) (Goldiamond, 1959, 1962, 1965, 1966; Nisbett & Wilson, 1977). Although there are many ways to interpret such terms, they all seem to involve circumstances in which individuals' own prior behavior is discriminative for their subsequent behavior. Behavior under the discriminative control of other behavior may be a kind of self-report (Skinner, 1957). The concepts of self-awareness and self-report can be studied as a behavioral process, without mentalistic inference. In the present research, pigeons were trained in a compound, discrete-trial ...