title: Differential Receptive Field Properties of Parvalbumin and Somatostatin Inhibitory Neurons in Mouse Auditory Cortex.
abstract: Cortical inhibitory circuits play important roles in shaping sensory processing. In auditory cortex, however, functional properties of genetically identified inhibitory neurons are poorly characterized. By two-photon imaging-guided recordings, we specifically targeted 2 major types of cortical inhibitory neuron, parvalbumin (PV) and somatostatin (SOM) expressing neurons, in superficial layers of mouse auditory cortex. We found that PV cells exhibited broader tonal receptive fields with lower intensity thresholds and stronger tone-evoked spike responses compared with SOM neurons. The latter exhibited similar frequency selectivity as excitatory neurons. The broader/weaker frequency tuning of PV neurons was attributed to a broader range of synaptic inputs and stronger subthreshold responses elicited, which resulted in a higher efficiency in the conversion of input to output. In addition, onsets of both the input and spike responses of SOM neurons were significantly delayed compared with PV and excitatory cells. Our results suggest that PV and SOM neurons engage in auditory cortical circuits in different manners: while PV neurons may provide broadly tuned feedforward inhibition for a rapid control of ascending inputs to excitatory neurons, the delayed and more selective inhibition from SOM neurons may provide a specific modulation of feedback inputs on their distal dendrites.
authors.affiliation: Zilkha Neurogenetic Institute Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Ling-Yun
authors.initials: LY
authors.lastname: Li
authors.affiliation: Zilkha Neurogenetic Institute Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Xiaorui R
authors.initials: XR
authors.lastname: Xiong
authors.affiliation: Zilkha Neurogenetic Institute Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Leena A
authors.initials: LA
authors.lastname: Ibrahim
authors.affiliation: Zilkha Neurogenetic Institute Department of Otolaryngology of Southwest Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yuan
authors.affiliation: Zilkha Neurogenetic Institute Department of Cell and Neurobiology.
authors.forename: Huizhong W
authors.initials: HW
authors.lastname: Tao
authors.affiliation: Zilkha Neurogenetic Institute Department of Physiology and Biophysics.
authors.forename: Li I
authors.initials: LI
authors.lastname: Zhang
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001303:Auditory Cortex / Q000166:cytology / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D008810:Mice, Inbred C57BL; D009433:Neural Inhibition / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D061848:Optical Imaging; D010320:Parvalbumins / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D013004:Somatostatin / Q000378:metabolism*; D013569:Synapses / Q000502:physiology
chemical_list: D010320:Parvalbumins; D013004:Somatostatin
keywords: auditory cortex; in vivo patch recording; inhibitory subtype; interneuron; two-photon imaging; whole-cell recording