Control of response reliability by parvalbumin-expressing interneurons in visual cortex

• Published in: Nature communications Vol. 6; no. 1; p. 6802
• Main Authors: Zhu, Yingjie, Qiao, Wenhui, Liu, Kefei, Zhong, Huiyuan, Yao, Haishan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.04.2015; Nature Publishing Group
• Subjects: 631/378/2571/1696; 631/378/2613; 64/60; Anesthesia; Animals; Evoked Potentials, Visual - genetics; Gene Expression; Genes, Reporter; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; Humanities and Social Sciences; Interneurons - cytology; Interneurons - metabolism; Mice; Mice, Transgenic; multidisciplinary; Neural Inhibition - genetics; Optogenetics; Parvalbumins - genetics; Parvalbumins - metabolism; Photic Stimulation; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Reproducibility of Results; Rhodopsins, Microbial - genetics; Rhodopsins, Microbial - metabolism; Science; Science (multidisciplinary); Signal-To-Noise Ratio; Somatostatin - genetics; Somatostatin - metabolism; Synaptic Transmission - genetics; Visual Cortex - cytology; Visual Cortex - metabolism; Wakefulness - physiology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms7802

The responses of visual cortical neurons to natural stimuli are both reliable and sparse. These properties require inhibition, yet the contribution of specific types of inhibitory neurons is not well understood. Here we demonstrate that optogenetic suppression of parvalbumin (PV)- but not somatostatin (SOM)-expressing interneurons reduces response reliability in the primary visual cortex of anaesthetized and awake mice. PV suppression leads to increases in the low firing rates and decreases in the high firing rates of cortical neurons, resulting in an overall reduction of the signal-to-noise ratio (SNR). In contrast, SOM suppression generally increases the overall firing rate for most neurons, without affecting the SNR. Further analysis reveals that PV, but not SOM, suppression impairs neural discrimination of natural stimuli. Together, these results reveal a critical role for PV interneurons in the formation of reliable visual cortical representations of natural stimuli. Natural stimuli evoke temporally reliable responses from visual cortical neurons, yet the underlying mechanisms are not well understood. Here, the authors demonstrate a critical role for parvalbumin- but not somatostatin-positive inhibitory interneurons in regulating visual cortical response reliability.