https://www.physiology.org/doi/abs/10.1152/jn.00053.2018
https://www.ncbi.nlm.nih.gov/pubmed/30625004?dopt=Abstract
Aberrant Thalamocortical Coherence in Animal Model of Tinnitus.
J Neurophysiol
Aberrant Thalamocortical Coherence in Animal Model of Tinnitus.
J Neurophysiol. 2019 Jan 09;:
Authors: Vilela-Rodrigues PV, Auerbach B, Salvi RJ
Abstract
Electrophysiological studies from humans suggest that the phantom sound of tinnitus is associated with abnormal thalamocortical neural oscillations. However, tinnitus models have seldom been tested in animal models where it is possible to simultaneously assess the neural oscillatory activity between the thalamus and auditory cortex. To explore this issue, we used multichannel electrodes to examine the oscillatory behavior of local field potentials recorded in the rat medial geniculate body (MBG) and primary auditory cortex (A1) before and after administering a dose of sodium salicylate (SS) that reliably induces tinnitus. In the MGB, SS reduced power and coherence in theta, alpha and beta oscillations, but increased coherence in the gamma band. Within A1, SS significantly decreased power and coherence between theta and alpha bands, but increased power and coherence in the gamma band. When coherence was measured between one electrode in the MGB and another in A1, SS decreased coherence in beta, alpha and theta bands, but increased coherence in the gamma band. SS also increased cross-frequency coupling between the phase of theta oscillations in the MGB and amplitude of gamma oscillations in A1. Altogether, our results suggest that SS treatment fundamentally alters how thalamocortical circuits communicate, leading to excessive cortical gamma power and synchronization, neurophysiological changes implicated in tinnitus. Our data provide support for element of both the thalamocortical dysrhythmia (TD) and synchronization-by-loss-of-inhibition (SLIM) models of tinnitus, demonstrating that increased cortical gamma is associated with both enhanced theta-gamma coupling as well as decreases alpha power/coherence between the MGB and A1.
PMID: 30625004 [PubMed – as supplied by publisher]
PubMed:30625004
