Abstract
Introduction:
Psychometric research has identified stable traits that predict inter-individual differences in relationship and attachment behavior. Avoidance and anxiety (AV/AX) scales have been developed to quantitatively assess these traits. However, neural mechanisms corresponding to the proposed constructs reflected in av/ax are still poorly defined. The ventral medial orbito-frontal cortex (vmOFC) is implicated in social approach network (SAN) function, and lateral orbitofrontal cortex (lOFC) is related in subserving emotion regulation on social processing . In this study, we examined whether functional connectivity between these regions predicts components of these scales.
Methods:
Paticipants: 23 healthy male, right-handed participants (mean age: 29.8 years, SD: 3.5 years), recruited via community announcements. Only participants with no current or prior neurological, psychiatric or other medical illness
were included in the study.
Psychological Measures: Participants' individual attachment style was measured using the German version of the Experiences in Close Relationships Questionnaire Revised (ECR-R) 3 . This questionnaire consists of 36 items, assessing individual needs, feelings, and behavior in relationships with an attachment avoidance and an attachment anxiety scale.
Data preprocessing and functional connectivity analysis: In each subject, resting-state functional magnetic resonance images
(TR=2.4) were acquired at baseline at a Siemens Trio 3T scanner. Distortion and online motion-correction were performed. Resting-state fMRI data were preprocessed using FSL 5.0.11 5 , standard preprocessing steps were applied. FIX toolbox 3 was used to eliminate artifacts. Using resting-state BOLD, we assessed correlations between structures of social approach network and those related subserving emotion, establishing single subject connectivity summary scores.
Results:
Summary scores were correlated with components of av/ax scores. Results demonstrate a novel correlation between AV in resting-state connectivity, and vmOFC- lOFC (r=-0.5784 p<0.003 Bonferroni corrected for 8 ROIs and 2 subscales) and hypocampus-lOfC (r=-0.3704 p<0.05). This implies that spontaneous synchrony between social approach processing regions may play a role in defining personality characteristics related to attachment.
Conclusions:
We studied the association between a specific personality trait and resting state, finding a significant correlation between functional connectivity in ventral Medial Orbitofrontal Cortex / lateral Orbitofrontal cortex, and attachment-avoidance ratings; the more avoidance the less activation/connectivity in these areas. These results are in line with the neuroanatomical model of social interaction, which states that avoidance trait reduces activity in areas which belongs to the social approach
network (vMOFC) and emotion regulation system (lOFC). As a general point of view these result suggest that certain patterns in RS across subjects could be related with expression in personality.
