Imaging attentional and attributional bias: an fMRI approach to the paranoid delusion

Background, The pathophysiology of auditory hallucinations and delusions of control has been elucidated using functional imaging. Despite their clinic al importance, there have been few similar attempts to investigate paranoid delusions. We have examined two components of social cognition (attentiona l and attributional biases) that contribute to the formation and maintenanc e of paranoid delusions, using functional magnetic resonance imaging (fMRI) . Method. Normal subjects performed tasks requiring attentional and attributi onal judgements. We investigated the neural response particularly associate d with attention to threatening material relevant to self and with the 'sel f-serving' attributional bias. Results. The determination of relevance to self of verbal statements of dif fering emotional valence involved left ventrolateral prefrontal cortex (lef t inferior frontal gyrus, BA 47), right caudate and right cingulate gyrus ( BA 24). Attention to threatening material relevant to self differentially a ctivated a more dorsal region of the left inferior frontal gyrus (BA 44). I nternal attributions of events, where the self was viewed as an active inte ntional agent, involved left precentral gyrus (BA 6) and left middle tempor al gyrus (BA 39). Attribution of events in a non 'self-serving' manner requ ired activation of the left precentral gyrus (BA 6). Conclusions, Anomalous activity or connectivity within these defined region s may account for the attentional or attributional biases subserving parano id delusion formation. This provides a simple model for paranoid delusion f ormation that can be tested in patients.