Callous unemotional (CU) traits (i.e., a lack of empathy/remorse and poverty of emotion) that co-occur with childhood antisocial behaviour are believed to be the developmental precursor to psychopathy in adulthood. An increasing volume of evidence supports two distinct variants of CU traits/psychopathy, known as primary and secondary. Primary variants are thought to show core deficits in emotional reactivity (e.g., attenuated autonomic activity), whereas secondary variants present with high levels of anxiety and this may be reflected in increased emotional sensitivity to (...) negative stimuli. -/- Aims: The current study is the first of its kind to examine the role of anxiety in modulating emotional processing as indexed by heart rate (HR) in incarcerated boys with CU traits. -/- Methods: HR was recorded continuously while 205 adolescents (aged 14 to 18 years) completed an emotional pictures dot-probe task. The task consisted of four blocks of 18 trials, beginning with a 500 ms central fixation cross, a 250 ms picture pair presentation (i.e., neutral, positive, negative valence), followed by a probe appearing in either the top or bottom picture location until response, and lastly a 2000 ms inter-trial interval recovery period. Four groups were formed on the basis of median-split scores on the Revised Children's Manifest Anxiety Scale and the Inventory of Callous Unemotional Traits, reflecting a primary variant (high CU/low anxiety), secondary variant (high CU/high anxiety), and two nonpsychopathic groups (low CU/high anxiety and low CU/low anxiety). -/- Results: The HR data indicated relative HR deceleration during the picture-probe period, regardless of group. Additionally, compared to all other groups, HR deceleration was greatest for the high CU/high anxiety secondary group and smallest for the high CU/low anxiety primary group during negative stimuli. Conclusions: This result is thought to reflect differences between CU/psychopathy variants in attentional orienting to distressing stimuli, consistent with theory. (shrink)