Evidence for mirror systems in emotions

Abstract

Why do we feel tears well up when we see a loved one cry? Why do we wince when we see other people hurt themselves? This review addresses these questions from the perspective of embodied simulation: observing the actions and tactile sensations of others activates premotor, posterior parietal and somatosensory regions in the brain of the observer which are also active when performing similar movements and feeling similar sensations. We will show that seeing the emotions of others also recruits regions involved in experiencing similar emotions, although there does not seem to be a reliable mapping of particular emotions onto particular brain regions. Instead, emotion simulation seems to involve a mosaic of affective, motor and somatosensory components. The relative contributions of these components to a particular emotion and their interrelationship are largely unknown, although recent experimental evidence suggests that motor simulation may be a trigger for the simulation of associated feeling states. This mosaic of simulations may be necessary for generating the compelling insights we have into the feelings of others. Through their integration with, and modulation by, higher cognitive functions, they could be at the core of important social functions, including empathy, mind reading and social learning.

Figure 1.

Anatomical locations of the motor and somatosensory components of simulation. (a) Lateral view of the human brain with the location of the ventral premotor cortex (BA6/BA44) and the inferior parietal lobule (IPL). (b) Lateral view showing the location of the primary and secondary somatosensory cortex (SI/SII).

Figure 2.

Anatomical locations of affective components of simulation. (a) Sagittal view of a human brain with the location of the anterior cingulate cortex (ACC). (b) Coronal view of a human brain showing the location of the insula and the amygdala.