Petilla terminology: nomenclature of features of GABAergic interneurons of the cerebral cortex

Debate continues over how best to classify cortical interneurons. Standardizing the nomenclature used to describe these cells might aid classification efforts. Here, a committee of interneuron researchers propose a standardized set of terms to describe the morphological, molecular and physiological features of an interneuron. Neuroscience produces a vast amount of data from an enormous diversity of neurons. A neuronal classification system is essential to organize such data and the knowledge that is derived from them. Classification depends on the unequivocal identification of the features that distinguish one type of neuron from another. The problems inherent in this are particularly acute when studying cortical interneurons. To tackle this, we convened a representative group of researchers to agree on a set of terms to describe the anatomical, physiological and molecular features of GABAergic interneurons of the cerebral cortex. The resulting terminology might provide a stepping stone towards a future classification of these complex and heterogeneous cells. Consistent adoption will be important for the success of such an initiative, and we also encourage the active involvement of the broader scientific community in the dynamic evolution of this project.