Borderline personality disorder (BPD) and schizotypal personality disorder (SPD) are both characterized by inflexible and pervasive behavioral patterns that frequently lead to significant functional impairment. Although considerable research has been conducted on the biological and phenotypic aspects of these disorders, researching, diagnosing, and treating them remains a challenge, primarily due to the difficulties associated with the categorical nature of current diagnostic methods (Skodol and Bender, 2009) which, in turn, results in significant within-group heterogeneity and between-group co-occurrence. Given the relative paucity of research comparing aspects of these disorders with one another, the current study aimed to evaluate overlapping and differentiating aspects of BPD and SPD by examining the integrity of a brain region frequently implicated in both disorders, the cingulum. The current study used a 3T Siemens scanner to acquire structural and diffusion tensor imaging in age-, sex-, and education-matched groups of 28 adults with BPD, 32 adults with SPD, and 36 healthy control participants (HC). The anterior and posterior cingulate were manually traced on all participants and then volume and fractional anisotropy (FA) comparisons were conducted across the groups for the left and right anterior and posterior cingulate. Compared with HC, SPD patients had smaller relative cingulate white matter volume and BPD patients had marginally significantly smaller relative cingulate white matter volume, and the two patient groups did not differ from one another. With regard to FA findings, a spectrum pattern emerged, such that the BPD group had significantly lower FA in the posterior cingulum relative to controls, whereas the SPD group also had lower FA in this region but did not differ from HC. The BPD group had marginally lower FA in dorsal aspects of the anterior cingulum when compared with HC, and the SPD patients did not differ from HC or BPD individuals. In summary, the current study provides evidence of aberrant connectivity of the cingulum in BPD patients, but not SPD patients, compared with HC individuals. Consistent with prior work, overall results suggest potential involvement of cingulum in BPD symptomatology. / Psychology

Thesis (M.A.)--The University of North Carolina at Greensboro, 2008. / Directed by Thomas Kwapil; submitted to the Dept. of Psychology. Title from PDF t.p. (viewed Jan. 28, 2010). Includes bibliographical references (p. ).

Individuals diagnosed with schizotypal personality disorder (SPD) exhibit patterns of cognitive deficits, neuromotor disturbances, and behavior problems similar to individuals with schizophrenia, and thus SPD is thought to represent one point on the continuum of schizophrenia spectrum disorders (SSDs). Deficits in behavior, cognition, and motor functioning have been implicated as childhood precursors of SSDs and appear to also vary as a function of gender and family history of psychopathology. As such, studies of youth may help in further identification of individuals at risk for SSDs. The current study examined the prospective associations between problem behaviors, neuromotor and neurocognitive functioning, as well as SSD symptoms, at baseline and 2-year follow-up in youth meeting criteria for SPD, other personality disorders, or healthy controls. The neuromotor and neurocognitive measures were able to significantly predict SSD symptoms and behavior problems above and beyond baseline predictors. Overall, the findings provide further support for the role of subcortical motor centers operating together with prefrontal cortical areas in the regulation of higher-order cognitive functioning and in producing the psychiatric features of SSDs. Significant correlations between gender, family history of schizophrenia, and history of head injury with symptoms, behavior, cognition, and motor functioning were also found and highlight the importance of examining the effects of these variables in future investigations. In sum, the current study helped in identifying factors that predict the clinical course of schizotypy and may shed light on the disturbed neural circuitry underlying SSDs.