Short-term deep brain stimulation of the thalamic reticular nucleus modifies aberrant oscillatory activity in a neurodevelopment model of schizophrenia.

Dysfunction of thalamo-cortical networks involving particularly the thalamic reticular nucleus (TRN) is implicated in schizophrenia. In the neonatal ventral hippocampal lesion (NVHL), a heuristic animal model of schizophrenia, brain oscillation changes similar to those of schizophrenic patients have been reported. The aim of this study was to analyze the effects of short-term deep brain stimulation (DBS) in the thalamic reticular nucleus on electroencephalographic (EEG) activity in the NVHL. Male and female Sprague-Dawley rats were used and the model was prepared by excitotoxicity damage of the ventral hippocampus on postnatal day 7 (PD-7). Chronic bilateral stainless steel electrodes were implanted in the TRN, thalamic dorsomedial nucleus and prelimbic area at PD-90. Rats were classified as follows: sham and NVHL groups, both groups received bilateral DBS in the TRN for one hour (100Hz, 100µs pulses, 200µA). All animals showed a sudden behavioral arrest accompanied by widespread symmetric bilateral spike-wave discharges, this activity was affected by DBS-TRN. Additionally, the power spectra of 0.5-100Hz and the coherence of 0.5-4.5 and 35-55Hz frequencies were modified by DBS-TRN. Our results suggest that DBS in the TRN may modify functional connectivity between different parts of the thalamo-cortical network. Additionally, our findings may suggest a beneficial effect of DBS-TRN on some preclinical aberrant oscillatory activities in a neurodevelopmental model of schizophrenia.