Dohoung Kim,1 Huijeong Jeong,2 Juhyeong Lee,2 Jeong-Wook Ghim,3 Eun Sil Her,3 Seung-Hee Lee,2 and Min Whan Jung1,2,3,4,*
1Graduate School of Medical Science and Engineering
2Department of Biological Sciences
Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
3Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon 34141, Korea
Inhibitory interneurons are thought to play crucial roles in diverse brain functions. However, roles of different inhibitory interneuron subtypes in working memory remain unclear. We found distinct activity patterns and stimulation effects of two major interneuron subtypes, parvalbumin (PV)- and somatostatin (SOM)-expressing interneurons, in the medial prefrontal cortex of mice performing a spatial working memory task. PV interneurons showed weak target-dependent delay-period activity and were strongly inhibited by reward. By contrast, SOM interneurons showed strong target-dependent delay-period activity, and only a subtype of them was inhibited by reward. Furthermore, optogenetic stimulation of PV and SOM interneurons preferentially suppressed discharges of putative pyramidal cells and interneurons, respectively. These results indicate different contributions of PV and SOM interneurons to prefrontal cortical circuit dynamics underlying working memory.