There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
The aim of this study was to investigate the effects of bilateral chemical lesion
of the rostral pole of the thalamic reticular nucleus on EEG activities in freely
moving rats applying quantitative analysis and brain mapping of power spectra distribution.
Ketamine-sedated Sprague-Dawley rats were implanted to monitor behavioral states with
frontoparietal electrodes in a first series of experiments and with multiple electrodes
along the antero-posterior axis (F1, F2, F7, F8, T3, T4, P3, P4) in a second series.
Monopolar and bipolar recordings were obtained in animals stereotaxically injected
with ibotenic acid into both rostral poles of the thalamic reticular nucleus. Long-term
video-EEG recordings and brain mapping based on quantitative spectral analysis were
made.
Two forms of dysrhythmia gradually emerged in the neocortical EEG at 12-24h post-injection:
potentiation of theta waves and spontaneous high-voltage spindles (HVS) at 4.5-8Hz
frequency. Brain mapping during these dysrhythmia shows highest power posteriorly
(parietotemporal) for theta and mesiofrontally for HVS.
Given the lack of inhibitory intrinsic interneurons in the rat thalamus, bilateral
destruction of a small part of the solely GABAergic population may promote cortical
dysrhythmia (probably by dis-inhibition). The topographic differences in power might
indicate different involved structures.