The brain network for self-feeling: a symptom-lesion mapping study

Ongoing signals from one's own body (interoception) allow experience of self-feeling. In early studies interoception strictly referred to the awareness of visceral sensation but recent theories have expanded this concept to denote the ongoing status of the body. Here we asked left and right focal brain-damaged patients to answer questions about their interoceptive feelings, and correlated their responses to a quantitative measure of their lesions (voxel-based symptom-lesion mapping). By these means we could reveal that three key structures contribute to building up the feeling of self, namely insula (interoceptive modulator), amygdala (emotional modulator) and putamen (motor modulator). This brain network may be necessary for the integrity of self-feeling. A dysfunction of this network might impair perception of the inner body state, and also account for psychological disturbances, such as the somatic symptom disorders, in which individuals experience subjective symptoms suggesting physical illness or injury despite medical test results which are normal, and clinical examination do not disclose relevant medical conditions.