There are patients with congenital insensitivity to pain (CIP) this is a rare condition. They don’t feel pain, cognition and sensation is otherwise normal; for instance they can still feel discriminative touch (though not always temperature), and there is no detectable physical abnormality. They offer a unique opportunity to test the model of empathy. Does the lack of self-pain representation influence the perception of others’ pain.

CIP patients globally underestimate the pain of others when emotional cues were lacking, and that their pain judgments, in contrast with those of control subjects, are strongly related to interindividual differences in empathy trait. More empathy better pain judgment.

Patients with CIP showed normal fMRI responses to observed pain. The same regions for observed pain in anterior mid-cingulate cortex and anterior insula, were activated. In contrast to healthy controls their empathy trait predicted ventromedial prefrontal responses to somatosensory representations of others’ pain and posterior cingulate responses to emotional representations of others’ pain. CIP patients can acknowledge the pain of others. The amount strongly correlates with their empathic capacity which mainly relies on the engagement of anterior the ventromedial prefrontal cortex (vmPFC) and posterior the ventral posterior cingulate cortex (vPCC) midline structures, which may in part compensate for the patients’ lack of automatic resonance mechanisms.

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