Event-Related Repetitive Transcranial Magnetic Stimulation of Posterior Superior Temporal Sulcus Improves the Detection of Threatening Postural Changes in Human Bodies

Department of Psychology, University of Rome La Sapienza, I-00185 Rome, Italy.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.75). 11/2011; 31(48):17547-54. DOI: 10.1523/JNEUROSCI.0697-11.2011
Source: PubMed

ABSTRACT Perceiving others' emotions through their body movements and postures is crucial for successful social interaction. While imaging studies indicate that perceiving body emotions relies upon a wide network of subcortico-cortical neural regions, little is known on the causative role of different nodes of this network. We applied event-related repetitive transcranial magnetic stimulation (rTMS) over nonfacial, body- and action-related extrastriate (EBA), temporal (pSTS), and premotor (vPM) cortices to test their active contribution in perceiving changes between two successive images of either threatening or neutral human body or animal postures. While stimulation of EBA and vPM showed no selective effect on threatening stimuli with respect to neutral ones, rTMS over pSTS selectively impaired neutral posture detection and increased the accuracy in detecting changes of threatening human postures with respect to all other experimental conditions. No such effect was found for animal stimuli. These results support the notion that pSTS is crucially devoted to the detection of socially relevant information concerning others' actions, fostering the notion that amygdalo-temporo-cortical modulatory connections mediate perception of emotionally salient body postures.

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