TXST Digital Repository

The Texas State University Digital Repository is the open access institutional repository for the university to collect, manage, share, and preserve free, worldwide access to research and scholarship of Texas State University faculty, staff, and students.

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    Virtual reality based active shooter training drill increases salivary and subjective markers of stress
    (2022-03-31) McAllister, Matthew J.; Martaindale, M. Hunter; Gonzalez, Andrew E.; Case, Marcus J.
    Law enforcement personnel are required to respond to a variety of dangerous, potentially life-threatening high stress scenarios. Virtual reality (VR)-based training has been shown to attenuate stress responses; however, little is known about the acute stress response from VR exposure. This study examined the impact of participating in a VR-based active shooter training drill (ASD) on markers of physiological stress as well as potential differences in men and women. To examine the impact of participation in a ~50 sec VR-based ASD, 29 subjects (n = 29; 17 males, 12 females) participated in a quasi-experimental single group design. Saliva samples were collected and analyzed from 27 of the 29 subjects a total of four times 1) 30-min prior to, 2) 5-min prior to, 3) 5-min after, and 4) 30-min after the ASD and analyzed for α-amylase (AA) activity and concentrations of secretory immunoglobulin-A (SIgA), cortisol (CORT), and uric acid (UA). Participation in the ASD resulted in a significant (p < 0.05) increase in salivary stress markers AA and SIgA. In addition, lower concentrations of CORT and UA were found in women compared to men. These findings have implications for law enforcement and/or military personnel that may seek to implement a VR-based training into their training regimen. Future studies should investigate the impact of longitudinal participation in ASD interventions to determine if this is an effective training method to reduce stress responses to real life active shooter training drills.
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    Impact of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality based active shooter training drill
    (2024-07-08) McAllister, Matthew J.; Martaindale, M. Hunter; Dillard, Courtney C.; McCullough, Rory
    Ingestion of L-theanine and L-tyrosine has been shown to reduce salivary stress biomarkers and improve aspects of cognitive performance in response to stress. However, there have been no studies to concurrently examine the impact of both L-theanine and L-tyrosine ingestion during a mental stress challenge (MSC) involving a brief cognitive challenge and a virtual reality based active shooter training drill. Thus, the purpose of this study was to determine the impact of ingestion of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality active shooter drill and cognitive challenge. The cognitive challenge involved a Stroop challenge and mental arithmetic. Eighty subjects (age = 21±2.6 yrs; male = 46; female = 34) were randomly assigned L-tyrosine (n=28; 2000mg), L-theanine (n=25; 200mg), or placebo (n=27) prior to MSC exposure. Saliva samples, state-anxiety inventory (SAI) scales, and heart rate (HR) were collected before and after exposure to the MSC. Saliva was analyzed for stress markers α-amylase (sAA) and secretory immunoglobulin A (SIgA). The MSC resulted in significant increases in sAA, SIgA, HR, and SAI. Ingestion of L-theanine and L-tyrosine did not impact markers of stress. However, the L-tyrosine treatment demonstrated significantly lower missed responses compared to the placebo treatment group during the Stroop challenge. These data demonstrate that ingestion of L-theanine or L-tyrosine does not impact markers of stress in response to a MSC but may impact cognitive performance. This study was pre-registered as a clinical trial ("Impact of supplements on stress markers”: NCT05592561).
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    Social demand for urban wilderness in purgatory
    (Springer Nature, 2022-07-01) Maleki, Shadi; Julian, Jason P.; Weaver, Russell; Lopez, Christina; Kraft, Michael
    In a rapidly urbanizing world, urban wilderness areas offer unique opportunities to connect with raw nature. After examining social demand for urban wilderness in one of the fastest growing cities in the United States, we found that high levels of naturalness positively influence visitors’ use and perception of natural areas. Age and youth experiences with nature were the most significant, positive correlates with perception of wildlife. Regardless of race/ethnicity, income, and education, visitors recognized the importance of wildlife in urban wilderness. Overall, this study found that social demand for urban wilderness is a multi-dimensional balance between natural amenities and cultural conveniences. This knowledge is useful to city planners to properly plan and protect the natural areas within urban environments.
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    A visual insight into tweeting activity before and during natural disasters: Case study of Hurricane Harvey
    (2021) Maleki, Shadi; Mohammadalizadehkorde, Milad
    Big data provided by social media has been increasingly used in various fields of research including disaster studies and emergency management. Effective data visualization plays a central role in generating meaningful insight from big data. However, big data visualization has been a challenge due to the high complexity and high dimensionality of it. The purpose of this study is to examine how the number and spatial distribution of tweets changed on the day Hurricane Harvey made landfall near Houston, Texas. For this purpose, this study analyzed the change in tweeting activity between the Friday of Hurricane Harvey and a typical Friday before the event.
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    #FalseFlag: Exploring themes in conspiracy theory tweets regarding the Robb Elementary School active shooter event
    (2024-09-15) Doyle, Madison; Martaindale, M. Hunter
    Little is known about the content of conspiratorial posts on social media, specifically regarding active shooter events. This study explores the content of conspiracy theory tweets during the six months following the active shooter event at Robb Elementary School in Uvalde, Texas. 194 tweets were analyzed. The analysis resulted in two main themes: False Flag and Hypothesized Reasoning. These themes represent the similarities and variations in content among the tweets. In line with research suggesting that people are most vulnerable to conspiratorial thinking when trying to explain unusual and unsettling events, results indicate that many posts were attempting to provide some kind of causal explanation for the event. Additional findings, implications, and directions for future research are also discussed.