Congratulations to Stephanie Taillefer, who successfully defended her doctoral dissertation entitled “Neurocognitive and Dysfunctional Belief Candidate Endophenotypes of Obsessive-Compulsive and Related Disorders.”


Stephanie’s dissertation examined neurocognitive and dysfunctional belief candidate endophenotypes (CEs) across the obsessive-compulsive spectrum. This study included CEs from two etiological perspectives well established in the literature. Secondary analyses examined several CEs multidimensionally and the relationship between CEs and quality of life. A total of 77 participants took part, divided into four groups: Obsessive-Compulsive Disorder (OCD; n = 21), Hoarding Disorder (HD; n = 16), Grooming Disorders (both Trichotillomania and Excoriation Disorder; n = 18), and control participants (n = 22). Participants completed a clinical interview and battery of neurocognitive tasks and questionnaires. Those with HD performed worse than controls on measures of response inhibition and set-shifting. OCD continued to predict significant variance in number sequencing. Examination of dysfunctional belief CEs revealed specificity of Responsibility/Threat beliefs and Importance/Control of Thoughts beliefs to OCD. Perfectionism/Intolerance of Uncertainty appear to be broad CEs; however, differing specificity emerged depending on the measure utilized to measure the construct. Differing patterns of quality of life impairments occurred across the spectrum. A better understanding of the specificity of CEs has implications for diagnostic classification, etiology, course, and treatment.


Stephanie is working as a clinician at the Operational Stress Injury Clinic in Dartmouth, Nova Scotia.


A special thank you to Stephanie’s Examining Committee, Dr. Tisha Ornstein, Dr. Todd Girard, Dr. Kristine Newman (Department of Nursing), and Dr. Steven Taylor (External Examiner from the University of British Columbia). Their thoughtful questions and comments were greatly appreciated. A big thanks also to Dr. Darko Joksimovic (Department of Civil Engineering) who chaired the defence. Many thanks as well to Dr. Peggy Richter and Dr. Tisha Ornstein who served on the Supervisory Committee.


Congratulations on a job well done, Stephanie!