Publication DetailsJ Neuroscience Acute Guinea Pig Cochlear Nucleus Penetrating Electrode
Tinnitus, the perception of phantom sounds, is thought to arise fromÂ increasedÂ neuralÂ synchrony, which facilitates perceptual binding and creates salient sensory features in the absence of physical stimuli. In the auditory cortex,Â increasedÂ spontaneous cross-unitÂ synchronyÂ and single-unit burstingÂ are de facto physiological correlates ofÂ tinnitus. However, it is unknown whether neurons in theÂ dorsalÂ cochlearÂ nucleusÂ (DCN), the putativeÂ tinnitus-induction site, exhibitÂ increasedÂ synchrony. Using a temporary-threshold shift model and gap-prepulse inhibition of the acoustic startle to assessÂ tinnitus, we recorded spontaneous activity fromÂ fusiformÂ cells, the principle neurons of the DCN, in normal hearing,Â tinnitus, and non-tinnitusÂ guinea pigs.Â SynchronyÂ andÂ bursting, as well as spontaneous firing rate (SFR), correlated with behavioral evidence ofÂ tinnitus, and increasedÂ synchrony andÂ burstingÂ were associated with SFR elevation. The presence of increased synchrony and burstingÂ in DCNÂ fusiform cellsÂ suggests that a neural code for phantom sounds emerges in this brainstem location and likely contributes to the formation of theÂ tinnitus percept.
J Neurosci.Â 2016 Feb 10;36(6):2068-73. doi: 10.1523/JNEUROSCI.3960-15.2016.http://www.jneurosci.org/content/36/6/2068.long February 10, 2016 University of Michigan