Format

Send to

Choose Destination
Neuron. 2017 Jul 19;95(2):412-423.e4. doi: 10.1016/j.neuron.2017.06.019. Epub 2017 Jul 6.

Network-Level Control of Frequency Tuning in Auditory Cortex.

Author information

1
Center for Neural Circuits and Behavior and Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA. Electronic address: hiroyuki_kato@med.unc.edu.
2
Center for Neural Circuits and Behavior and Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA.
3
Center for Neural Circuits and Behavior and Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA. Electronic address: jisaacson@ucsd.edu.

Abstract

Lateral inhibition is a fundamental circuit operation that sharpens the tuning properties of cortical neurons. This operation is classically attributed to an increase in GABAergic synaptic input triggered by non-preferred stimuli. Here we use in vivo whole-cell recording and two-photon Ca2+ imaging in awake mice to show that lateral inhibition shapes frequency tuning in primary auditory cortex via an unconventional mechanism: non-preferred tones suppress both excitatory and inhibitory synaptic inputs onto layer 2/3 cells ("network suppression"). Moreover, optogenetic inactivation of inhibitory interneurons elicits a paradoxical increase in inhibitory synaptic input. These results indicate that GABAergic interneurons regulate cortical activity indirectly via the suppression of recurrent excitation. Furthermore, the network suppression underlying lateral inhibition was blocked by inactivation of somatostatin-expressing interneurons (SOM cells), but not parvalbumin-expressing interneurons (PV cells). Together, these findings reveal that SOM cells govern lateral inhibition and control cortical frequency tuning through the regulation of reverberating recurrent circuits.

PMID:
28689982
PMCID:
PMC5705232
DOI:
10.1016/j.neuron.2017.06.019
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center