| First Author | Miska NJ | Year | 2018 |
| Journal | Elife | Volume | 7 |
| PubMed ID | 30311905 | Mgi Jnum | J:269760 |
| Mgi Id | MGI:6269274 | Doi | 10.7554/eLife.38846 |
| Citation | Miska NJ, et al. (2018) Sensory experience inversely regulates feedforward and feedback excitation-inhibition ratio in rodent visual cortex. Elife 7:e38846 |
| abstractText | Brief (2-3d) monocular deprivation (MD) during the critical period induces a profound loss of responsiveness within binocular (V1b) and monocular (V1m) regions of rodent primary visual cortex. This has largely been ascribed to long-term depression (LTD) at thalamocortical synapses, while a contribution from intracortical inhibition has been controversial. Here we used optogenetics to isolate and measure feedforward thalamocortical and feedback intracortical excitation-inhibition (E-I) ratios following brief MD. Despite depression at thalamocortical synapses, thalamocortical E-I ratio was unaffected in V1b and shifted toward excitation in V1m, indicating that thalamocortical excitation was not effectively reduced. In contrast, feedback intracortical E-I ratio was shifted toward inhibition in V1m, and a computational model demonstrated that these opposing shifts produced an overall suppression of layer 4 excitability. Thus, feedforward and feedback E-I ratios can be independently tuned by visual experience, and enhanced feedback inhibition is the primary driving force behind loss of visual responsiveness. |
