Roughly 20% of the neurons in the mouse cortex are inhibitory interneurons (INs). Of these, the three major subtypes are parvalbumin (PV), somatostatin (SST), and vasoactive intestinal polypeptide (VIP) expressing neurons. We used monosynaptic rabies tracing to compare the presynaptic input landscape onto these three IN subtypes in the mouse primary auditory cortex (A1). We compared both local patterns of monosynaptic inputs as well as long-range input patterns. The local monosynaptic input landscape to SST neurons was more widespread as compared to PV and VIP neurons. The brain-wide input landscape was rich and heterogeneous with >40 brain regions connecting to all the three INs subtypes from both hemispheres. The general pattern of the long-range input landscape was similar among the groups of INs. Nevertheless, a few differences could be identified. At low resolution, the proportion of local versus long-range inputs was smaller for PV neurons. At mesoscale resolution, we found fewer inputs from temporal association area to VIP INs, and more inputs to SST neurons from basal forebrain and lateral amygdala. Our work can be used as a resource for a quantitative comparison of the location and level of inputs impinging onto discrete populations of neurons in mouse A1.
Bibliographical noteFunding Information:
We thank Dr. Maya Groysman for providing all adeno‐associated viruses used in this study through the ELSC vector core facility at the Hebrew University of Jerusalem. We thank members of the Mizrahi laboratories for comments on the manuscript. This work was supported by an ERC grant (#616063), and an ISF grant (#2453/18) to AM. GT was supported by a postdoctoral fellowship from the Uehara Memorial Foundation and the Edmond and Lily Safra Center for Brain Sciences.
© 2022 The Authors. The Journal of Comparative Neurology published by Wiley Periodicals LLC.
- auditory cortex
- inhibitory neurons
- monosynaptic rabies tracing