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Psychopathy is a personality disorder that manifests as a syndrome characterised by prominent affective and interpersonal deficits and persistent patterns of disruptive and antisocial behaviours (1). Psychopathy has been linked to atypical functioning within and between brain networks (2). However, most existing evidence suffers from two notable sampling limitations, namely an over-reliance on male samples from forensic and clinical populations and an absence of studies including non-Western populations. Thus, limiting generalisability and obscuring potential sex or cultural differences. The present study investigates whether previously observed neural correlates of psychopathy and its subcomponent facets are also present in a non-Western, mixed-sex community sample.<br/><br/>Here, we used resting-state functional magnetic resonance imaging (rs-fMRI) to examine functional connectivity in 92 Japanese adults (43 males), aged 21–39, drawn from a well-functioning community population. Participants completed the Self-Report Psychopathy Scale – Short Form (SRP-SF), a widely used dimensional measure of psychopathic traits that provides a total score for overall psychopathy along with four sub-scale scores for each of the facets (Antisocial behaviour, Callous affect, Interpersonal manipulation and Erratic lifestyle). Resting-state scans were analysed using the CONN toolbox (3) in SPM12 (4). Preprocessing included realignment, slice-timing correction, segmentation, normalisation to MNI space, smoothing, and denoising via CompCor and motion regression. Functional connectivity was examined across inter- and intra-network interactions between regions within the Default Mode Network (DMN), Salience Network, Control Network, and Subcortical regions, using the Schaefer-Yeo parcellation.<br/><br/>We found that total psychopathy scores significantly interacted with sex to predict connectivity between the DMN and salience network. Specifically, regression analysis showed that for males, higher psychopathy scores were significantly associated with decreased connectivity. In contrast, this relationship was not observed in females. These results indicate a divergent pattern of brain connectivity associated with psychopathic traits in males and females.<br/><br/>These findings extend existing work by demonstrating associations between psychopathic traits and brain connectivity in a non-Western, community-based sample. In addition, to our knowledge, this is the first study to show that males and females differ in the direction of connectivity between the default mode and salience networks. This observed sex difference may reflect alternative neural strategies, compensatory processes, or divergent developmental pathways in how psychopathy is expressed and supported by brain networks.<br/><br/>By identifying sex-specific associations in a diverse sample, this study underscores the importance of moving beyond homogenous forensic populations in psychopathy research. The results support growing calls for culturally informed and sex-sensitive neurodevelopmental models that better capture the variability and complexity of psychopathic traits across populations.