Optogenetic activation of an inhibitory network enhances feedforward functional connectivity in auditory cortex

Neuron. 2013 Nov 20;80(4):1066-76. doi: 10.1016/j.neuron.2013.08.017.


The mammalian neocortex is a highly interconnected network of different types of neurons organized into both layers and columns. Overlaid on this structural organization is a pattern of functional connectivity that can be rapidly and flexibly altered during behavior. Parvalbumin-positive (PV+) inhibitory neurons, which are implicated in cortical oscillations and can change neuronal selectivity, may play a pivotal role in these dynamic changes. We found that optogenetic activation of PV+ neurons in the auditory cortex enhanced feedforward functional connectivity in the putative thalamorecipient circuit and in cortical columnar circuits. In contrast, stimulation of PV+ neurons induced no change in connectivity between sites in the same layers. The activity of PV+ neurons may thus serve as a gating mechanism to enhance feedforward, but not lateral or feedback, information flow in cortical circuits. Functionally, it may preferentially enhance the contribution of bottom-up sensory inputs to perception.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acoustic Stimulation
  • Algorithms
  • Animals
  • Auditory Cortex / cytology
  • Auditory Cortex / physiology*
  • Channelrhodopsins
  • Dependovirus
  • Electrodes
  • Electrophysiological Phenomena
  • Evoked Potentials / physiology
  • Feedback, Physiological / physiology*
  • Immunohistochemistry
  • Mice
  • Mice, Transgenic
  • Models, Neurological
  • Nerve Net / physiology*
  • Neural Pathways / physiology*
  • Optogenetics*
  • Parvalbumins / metabolism
  • Signal-To-Noise Ratio


  • Channelrhodopsins
  • Parvalbumins