Strength in Weakness: Slow Excitation Increases Temporal Precision of Sound Offset Encoding

Material below summarizes the article Slow NMDA-Mediated Excitation Accelerates Offset-Response Latencies Generated via a Post-Inhibitory Rebound Mechanism, published on May 31, 2019, in eNeuro and authored by Ezhilarasan Rajaram, Carina Kaltenbach, Matthew J. Fischl, Leander Mrowka, Olga Alexandrova, Benedikt Grothe, Matthias H. Hennig, and Conny Kopp-Scheinpflug.

Highlights

• In response to short sound stimuli in vivo, some superior paraolivary nucleus (SPN) neurons display only offset responses (OFF-only), while others display both onset and offset responses (ON-OFF).

• The response to the end of the acoustic stimulus in these ON-OFF neurons occurs significantly faster in comparison to OFF-only neurons and is surprisingly invariant to changes in sound intensity.

• The presence of strong inhibition and weak excitation in SPN neurons as identified by patch-clamp recordings was fed into a computational model, which indicated that NMDA receptors, though weakly expressed, play an important role in improving the temporal precision of the offset response.