Text

theses

Borderline personality disorder (BPD) is a complex disorder characterized by intense and rapidly shifting affective states, instability in self-image, chronic feelings of emptiness, and dissociation. Individuals with BPD commonly engage in substance use, and self-injurious and suicidal behaviors as a way to manage intolerable affect. To date, the cognitive components of emotion dysregulation in BPD have received much research attention. The collateral psychophysiological processes, however, remain poorly understood. Because emotion regulation is mediated by both cognitive and physiological processes, this knowledge gap may be limiting progress in the treatment of BPD. Thus, this investigation sought to comprehensively assess psychophysiological differences between individuals with BPD and healthy controls, and examine whether a loss of flexibility in fundamental autonomic nervous system (ANS) processes may contribute to the emotion dysregulation observed in BPD. Psychophysiological differences between individuals with BPD and healthy controls were assessed at rest, during exposure to emotionally evocative images selected from the International Affective Picture System (IAPS), and during a post cue exposure recovery period, with additional tests for the effects of dissociative tendencies on cue reactivity, and substance use on cue exposure recovery. Indices of heart rate variability (HRV), electrocardiogram (ECG) derived measures of neurocardiac signaling, as well as continuously recorded blood pressure (BP) and skin conductance (SC) were used to operationalize modulation of psychophysiological arousal. At baseline, the BPD group showed significantly higher heart rate (HR) and greater skin conductance variance (SCV) compared to the control group, but were similar on measures of HRV and blood pressure variability (BPV). Across tasks, there were significant main effects of group and time (cue reactivity and cue recovery) on HR and SCV, and a main effect of time for HRV. However, no interaction effects were observed, suggesting groups were not different in how they responded to or recovered from exposure to emotionally evocative stimuli. This was in spite of the fact that participants with BPD rated the images as subjectively more arousing than controls. Notably though, a posteriori analyses found that BPD severity moderated psychophysiological response to, as well as recovery from, exposure to emotionally evocative images. In addition, analyses for the effects of trait dissociative tendencies on cue reactivity showed trait dissociation moderated change in HRV and BPV from baseline to cue exposure. Analyses for the effects of substance use on cue exposure recovery, however, were limited by unanticipated low levels of past month and past year substance use within the BPD group, though past month alcohol use negatively impacted systolic arterial blood pressure variability during recovery from exposure to emotionally evocative images. Results are discussed within the context of polyvagal theory and future research directions are considered.

ETD_6722

Ph.D.

Includes bibliographical references

by David Eddie

doi:10.7282/T3RB76W5

ETD doctoral

The author owns the copyright to this work.