Typical neuronal activity patterns of the relay and nonspecific thalamic nuclei in patients with spasmodic torticollis

• Published in: Human physiology 2015-05, Vol.41 (3), p.280-288
• Main Authors: Devetiarov, D. A., Semenova, U. N., Butiaeva, L. I., Sedov, A. S.
• Format: Article
• Language: English
• Subjects: Biomedicine; Human Physiology; Life Sciences
• ISSN: 0362-1197; 1608-3164
• DOI: 10.1134/S0362119715020048

Unit activity of 50 neurons of the nonspecific (Rt and MD) and relay (Voi and Voa) thalamic nuclei was recorded extracellularly during 14 stereotactic surgeries in spasmodic torticollis patients by a microelectrode technique. An analysis with Poincare maps and gap statistics revealed three main neuronal activity patterns: irregular single spikes, low-threshold Ca 2+ -dependent rhythmic (3–5 Hz) bursts, and combinations of bursts and single spikes. Grouping (in the Voi and Rt nuclei) and long-burst (in the Voa nucleus) patterns were observed in a few cases. The grouping pattern consisted of low-density groups of spikes with random lengths and a tendency to periodicity in the range from 1 to 1.5 Hz. The long-burst pattern consisted of long dense groups of spikes with random lengths and invariant interburst intervals. Main numerical parameters of the three most common neuronal activity patterns were estimated by a parametric analysis. The thalamic nuclei substantially differed in burst activity characteristics, while their average firing rates did not differ significantly. The results may be used for functional identification of the thalamic nuclei during stereotactic neurosurgery in patients with movement disorders.