Background: Affective dysregulation in borderline personality disorder (BPD) in response to both external stimuli and memories has been shown to be associated with functional alterations of limbic and prefrontal brain areas. This study aimed to examine neuronal networks involved in autobiographical memory retrieval using standardized stimuli that gain autobiographical significance by illustrating marked solitary and social situations of human life.
Methods: Using event-related functional Magnetic Resonance Imaging (fMRI), we examined the processing of pictures from the Thematic Apperception Test (TAT) in 14 BPD patients and 14 controls.
Results: In both groups, TAT stimuli activated brain areas known to be involved in autobiographical memory retrieval. BPD subjects lacked differential amygdala, orbitofrontal and cingulate activations for TAT versus neutral stimuli. In the TAT condition, compared to controls, BPD subjects displayed increased BOLD responses in the bilateral orbitofrontal and insular regions, in the left anterior cingulate and medial prefrontal cortex, as well as in the parietal and parahippocampal areas, consistent with a more aversive and arousing experience assessed by self-reports.
Conclusions: Increased BOLD responses during TAT processing in BPD subjects were in line with previously reported changes in anterior cingulate and orbitofrontal cortices, which are known to be involved in memory retrieval. However, BPD subjects displayed hyperactivation in these areas for both TAT and neutral stimuli. The deficit of selective activation of areas involved in autobiographical memory retrieval suggests a general tendency towards a self-referential mode of information processing in BPD, or a failure to switch between emotionally salient and neutral stimuli.