Jordan Sieja

Date Approved


Degree Type

Open Access Thesis

Degree Name

Master of Science (MS)

Department or School


Committee Member

Ellen Koch, PhD

Committee Member

Karen Saules, PhD

Committee Member

Chong Man Chow, PhD


Anxiety sensitivity (AS), or the fear/belief that anxiety symptoms and sensations will have negative outcomes, is a strong predictor of future psychopathology. AS is divided into three factors: physical, cognitive, and social. Reduced heart rate variability (HRV), or the variation in intervals between heartbeats, is associated with various psychological disorders. Current research findings disagree as to whether AS predicts HRV outcomes. The present study sought to examine data from a previous research project as results of relationships between AS and HRV were contrary to expectations. The current study examined potential predictors of HRV, such as the relationship between high-frequency (HF) and low-frequency (LF) HRV, the timing of administration of the Anxiety Sensitivity Index-3 (ASI-3), gender, and level of AS. HF- and LF-HRV were perfectly linearly related, providing support in reporting one index since it can infer dominant nervous system response in the moment. Furthermore, findings suggested reliability and internal consistency of the ASI-3 across online and in-person administrations. Gender was also differentially associated with ASI-3 scores and HRV, but it did not moderate effects between ASI-3 scores and HRV. Finally, study results provided some support of the Trier Social Stress Test for the social dimension of AS. A discussion of what variables should be considered when examining HRV is addressed as well as how current findings relate and add knowledge to the existing literature regarding the relationship between AS and HRV.