Neural Circuits of Emotion Discrimination
- Francesco Papaleo, Tenured Senior Researcher, Neuroscience Area, Istituto Italiano di Tecnologia, Genova, Italy and Adjunct Faculty Investigator, Lieber Institute for Brain Development. Baltimore, MD, USA.
Emotion recognition and consequent social reaction are important for a wealthy animal life. These socio-cognitive processes are supposed to rely on evolutionary conserved long-range brain networks, regulated by an inhibitory/excitatory balance. We found that inhibitory somatostatin (SOM) neurons within the medial prefrontal cortex (mPFC) are a fundamental biological substrate of emotion discrimination. However, it is unclear how cell-specific long-range circuits might process socially derived information for reliable emotion recognition.
Here, we show the specific involvement of atypical long-range SOM projections from the mPFC to the retrosplenial cortex (RSC), and an excitatory feedback loop from the RSC to mPFC in emotion discrimination. Using human imaging and rodent anatomical tracing, we highlight the involvement of the mPFC-RSC network in emotion recognition and the existence of a subpopulation of SOM GABAergic neurons projecting from the mPFC to the RSC. Our findings demonstrate a specific cortico-cortical inhibitory/excitatory circuit subtending emotion recognition.