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Full-Text Articles in Cognition and Perception

Hiv And Early Life Stress On Neuroimaging And Risky Behavior, Paola Garcia Egan Nov 2022

Hiv And Early Life Stress On Neuroimaging And Risky Behavior, Paola Garcia Egan

Dissertations

This study examined the interactive effects of early life stress (ELS) and HIV on brain morphometry, diffusion-basis-spectrum-imaging (DBSI), risky decision-making, and sex-risk behavior. 122 people with HIV (PWH) and 113 people without HIV (PWoH), free of major psychiatric illness and neurological confounds, were stratified into high (≥ 3 events) vs. low (< 3 events) ELS [PWoH/low ELS (n = 57), PWoH/high ELS (n =56), PWH/low ELS (n = 43), PWH/high ELS (n = 79)] and underwent structural magnetic resonance imaging, DBSI, neuropsychological, and risky-behavior assessment; all PWH were virologically controlled. Compared to PWoH, PWH had smaller orbitofrontal cortex (OFC), parietal lobes, insula, caudate and anterior cingulate. No ELS effects were detected in volumetric measures. Significant interactions were found between HIV serostatus and ELS on the OFC and on cellularity of the inferior fronto-occipital fasciculus after multiple comparisons adjustment. Specifically, PWH/high ELS exhibited significantly smaller OFC and PWoH/high ELS show significantly larger OFC than the other groups. PWoH/high ELS exhibited higher DBSI cellularity (neuroinflammation proxy) of the inferior-occipital-fasciculus compared to PWoH/high ELS. Regardless of HIV status, executive function moderated the relationship between the OFC and sex-risk behavior such that individuals within the sample who performed above average on a measure of executive function and had a larger OFC reported fewer sex partners in past six months than individuals with smaller volumes. No interaction was found between HIV serostatus and ELS on risky behavior measures. Clustering analyses defined ELS subgroups in PWH that were determined by demographic characteristics, duration of infection, recent CD4+ T-cell count, nadir CD4+ T-cell count and high/low ELS.Even in PWH that are virologically controlled, without major current psychiatric comorbidities, there is evidence of a synergistic impact of ELS and HIV on OFC volumes. Higher volumes in the OFC were detrimental when associated with lower executive function scores or advantageous when associated with higher executive function. Findings suggest that ELS is associated with different brain signatures among PWoH and virally suppressed PWH. However, ELS was not directly associated with risky behaviors, and subgroups in PWH were characterized by demographic variables, past substance use and HIV clinical variables.


Lifetime Racism And John Henryism On Cognition And Cardiovascular Health In Black Men, Roy Mitchell Aug 2022

Lifetime Racism And John Henryism On Cognition And Cardiovascular Health In Black Men, Roy Mitchell

Dissertations

Lifetime racism is a type of chronic stress that is often accompanied by depression. Racism is the experience of many Black men because of several psychosocial stressors such as reduced resources and institutional barriers, to name a few. Active coping is typically utilized by Black men as a consistent means to reduce the negative outcomes linked to racism, however, this up-tempo coping style can contribute to poor cardiovascular health and cognitive impairment over time. The present study aimed to provide data to support the effects of lifetime racism and active coping on cardiovascular health and cognition. There were three hypotheses …


The Impact Of Juvenile Offender Race On Public Perception Of Crime Seriousness, Megan Whitaker Jul 2022

The Impact Of Juvenile Offender Race On Public Perception Of Crime Seriousness, Megan Whitaker

Dissertations

Public perception of crime is an important focus of research, especially when considering juvenile offenders. However, there is very limited research in this area. This study looked at how the public perceives crime seriousness and how race of the juvenile offender impacts the overall seriousness rating. An online survey that included 15 crime scenarios was completed by 176 participants. It was hypothesized that a crime would be rated as more severe when the juvenile offender is African American as compared to a Caucasian juvenile offender. Results found that participants overall rated the seriousness of offenses as significantly higher for Caucasian …


Does Optic Flow Provide Information About Actions?, Hannah Masoner May 2022

Does Optic Flow Provide Information About Actions?, Hannah Masoner

Dissertations

Optic flow, the pattern of light generated in the visual field by motion of objects and the observer’s body, serves as information that underwrites perception of events, actions and affordances. This visual pattern informs the observer about their own actions in relation to their surroundings, as well as those of others. This study explored the limits of action detection for others as well as the role of optic flow. First-person videos were created using camera recordings of the actor’s perspective as they performed various movements (jumping jacks, jumping, squatting, sitting, etc.). In three experiments participants attempted to detect the action …


Does Optic Flow Provide Information About Actions?, Hannah Masoner Mar 2022

Does Optic Flow Provide Information About Actions?, Hannah Masoner

Dissertations

Optic flow, the pattern of light generated in the visual field by motion of objects and the observer’s body, serves as information that underwrites perception of events, actions and affordances. This visual pattern informs the observer about their own actions in relation to their surroundings, as well as those of others. This study explored the limits of action detection for others as well as the role of optic flow. First-person videos were created using camera recordings of the actor’s perspective as they performed various movements (jumping jacks, jumping, squatting, sitting, etc.). In three experiments participants attempted to detect the action …