McNair Scholars

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Recent Submissions

  • Publication
    Attentional biases toward internal and external threat in anxiety: Insights from the stimulus-preceding negativity
    (Oklahoma State University, 2021-03-12) Beugelsdyk, Lauren A.
    Generalized Anxiety Disorder (GAD) is characterized by excessive and uncontrollable worry. Individuals who experience high levels of worry have unconscious attentional biases toward threatening stimuli and display a higher amount of anticipatory processing immediately prior to the onset of threat cues. The current study examined eventrelated brain potentials, particularly the stimulus-preceding negativity, to evaluate if attention to an internal source of threat, such as elevated heart rate, can act as a distraction from a subsequent external source of threat. Participants were placed into high and low worry groups and engaged in an S1/S2 task, in which 25% of S1 stimuli were designed to draw attention toward an internal threat (elevated heart rate), before exposure to either an emotional or neutral S2. Results found that those who viewed the S1 distractor heart rate cue showed less anticipatory processing for the following S2, as indexed by a less negative amplitude of the stimulus-preceding negativity. A moderately significant relationship was also found between group and cue, indicating that these results may be applicable to other populations, such as individuals with social anxiety. These findings are in line with the existing literature regarding attentional biases and anticipatory processing in anxiety disorders. Implications and limitations of the present results, as well as suggestions for future studies are discussed.
  • Publication
    Restoring eastern redcedar encroached watersheds to prairie or switchgrass improves water quality and quantity
    (Oklahoma State University, 2019-07-25) DeRoin, Rainee; Zou, Chris; Saenz, Adrian; Will, Rodney
    Eastern redcedar represents a modern-day challenge to Oklahoma as it has encroached approximately eight million acres of land. This conversion is detrimental to the ecological and economic value of the land, reducing ecosystem water provisioning in particular. Eastern redcedar trees consume more water such that less is available for municipal and agricultural uses as well as ecological stream flows. Currently, efforts to reduce eastern redcedar encroachment have been unsuccessful; however, studies have shown eastern redcedar biomass to be a potential ethanol feedstock for the state. The purpose of this study is to compare eastern redcedar removal and replacement with native prairie or planted switchgrass on surface runoff, sediment yield, and biomass production. More specifically, this study monitors surface runoff and sediment yield of encroached eastern redcedar, harvested eastern redcedar, cultivated switchgrass, and native prairie using experimental watersheds (5-10 acres in size). Preliminary analysis shows that removal of eastern redcedar increased water yield by 4-5 fold. Growing switchgrass produced more biomass than restoration to native prairie, but water yield did not differ between the two. Sediment concentrations from encroached eastern redcedar watersheds were higher compared to native prairie watersheds. After harvest, previously encroached watersheds initially experienced an increase in sediment yield due to soil disturbance. After switchgrass and native vegetation re-established, sediment yields declined. These results indicate that water yield and biomass production can be increased by converting eastern redcedar woodlands to switchgrass for use as dedicated biofuel feedstock.
  • Publication
    Quantifying the shifted baseline in breeding bird communities for Native American tribes relocated to Oklahoma
    (Oklahoma State University, 2019-07-25) Stevens, Madison Mackenzie; O'Connell, Timothy
    Ecosystem services are often recognized for their importance in productivity (e.g., Nitrogen fixation) or biosphere support (Oxygen production from photosynthesis). Cultural ecosystem services (e.g., biodiversity appreciation) are no less important to human well-being but are undervalued when incremental losses go unrecognized by subsequent generations. This phenomenon referred to as generational amnesia or more commonly a shifted baseline of biodiversity understanding. The baseline serves as a control for what is considered normal in that ecosystem and what changes are measured against. Shifted baselines are especially damaging in cultures for which a connection to Nature is emphasized as a point of identity. In the United States, the forced relocation of Native Americans to Oklahoma Territory in the 19th and 20th centuries represents an extreme shifted baseline that severed important biodiversity connections in a single generation. The main purpose of this study was to quantify shifted baselines of breeding bird biodiversity for multiple Native American tribes now based in Oklahoma. The data used for this project was collected through eBird, a volunteer-based citizen science database, from fifteen different tribes who currently have jurisdictions in Oklahoma. Additionally, data from geographic regions where these tribes are originally from prior to their relocation to Oklahoma was also collected. We used beta diversity to quantify estimates of bird community difference and loss between ancestral and Oklahoma lands. Results showed eleven of the fifteen tribes experienced a community dissimilarity over 50% between their ancestral lands and Oklahoma areas. This means these tribes experienced a change in over half of the bird communities, ancestral baseline species, they encountered upon relocation to Oklahoma. This not only shows a significant shift in bird communities experienced by the tribes, but could also provide insight to other drastic shifting baselines these tribes had to endure upon their forced removal from their ancestral lands.
  • Publication
    Laying the groundwork for resilience and success: How a supportive community can protect against the effects of poverty
    (Oklahoma State University, 2019-07-25) Dang, Tinh Ngoc; Erato, Gina; Addante, Sam; Ciciolla, Lucia
    BACKGROUND: The negative effects of poverty includes increased risks for developmental delays, low academic achievement, poor physical and mental health, and impairments from overall stress (Hair, Hanson, Wolfe, & Pollak, 2015; Evans & Schamberg, 2009), with evidence that impairments continue into adulthood (Duncan, Magnuson, Kalil, & Ziol-Guest, 2012). However, little is known about protective community factors, like mentorship, and their role in the relationship between childhood poverty, academic achievement, and overall life stress. The current study investigated the moderating effects of supportive community mentorship on the association between childhood poverty and overall stress and academic achievement in college.