Honors Program


Date of this Version

Spring 4-12-2024

Document Type



Speakar, Brianna. Health Behavior Moderates Relationships Between Sickness Behavior, Mood, and Attenuated Positive Psychotic Symptoms. Undergraduate Honors Thesis. University of Nebraska-Lincoln. 2024


Copyright Brianna Speakar 2024


Serious mental Illness (SMI) is linked to a two to three times higher mortality rate compared to the general population, primarily due to health conditions involving inflammation. Inflammation’s role in SMI may extend to symptoms often attributed to psychopathology via induction of sickness behaviors – a suite of cognitive, affective, and behavioral changes induced by inflammation which evolved to promote recovery during acute illness. The pro-inflammatory cytokines that commonly induce sickness behaviors are also positively associated with clinical measures of anxiety, depression, and positive attenuated psychosis, pointing to potential shared pathways. Insomnia is associated with higher inflammatory profiles, while physical activity is associated with lower inflammation. This study evaluates the moderating roles of physical activity and sleep disturbance on the relationships between sickness behavior and inflammation-related psychiatric presentations (e.g., depression, anxiety, attenuated positive psychotic symptoms), using self-report data from college students. Greater insomnia was significantly associated with stronger relationships between sickness behaviors and depression, anxiety, and attenuated positive psychotic symptoms. Higher levels of physical activity were significantly associated with weaker relationships between sickness behavior and depression and attenuated positive psychotic symptoms, while the same effect was non-significant for anxiety. These results highlight the importance of further investigation on health behaviors such as sleep and physical activity as potential intervention targets for emerging adults experiencing inflammation related psychiatric presentations.