• DOI:10.1152/JN.00363.2004
• Corpus ID: 14911132

Very fast oscillations evoked by median nerve stimulation in the human thalamus and subthalamic nucleus.

@article{Hanajima2004VeryFO,
  title={Very fast oscillations evoked by median nerve stimulation in the human thalamus and subthalamic nucleus.},
  author={Ritsuko Hanajima and Robert Chen and Peter Ashby and Andres M. Lozano and William D. Hutchison and Karen Deborah Davis and Jonathan O. Dostrovsky},
  journal={Journal of neurophysiology},
  year={2004},
  volume={92 6},
  pages={
          3171-82
        }
}

• R. Hanajima, Robert Chen, +4 authors J. Dostrovsky
• Published 1 December 2004
• Biology
• Journal of neurophysiology

Very fast oscillations (VFOs; 500-1,500 Hz) are associated with sensory-evoked potentials (SEPs), but their origin is unknown. To characterize the origins of VFOs, we studied 35 patients with deep brain stimulation (DBS) electrodes [15 with thalamic and 20 with the subthalamic nucleus (STN) electrodes]. We recorded median nerve stimulation-evoked SEPs from the thalamus and STN with microelectrodes during stereotactic surgery and from the contacts of the DBS electrodes postoperatively. We also examined the firing of individual neurons in thalamus in relation to the VFOs. In the thalamus, VFOs with frequencies around 1,000 Hz were superimposed on slow potentials. Both slow and fast SEP components showed phase reversals in the somatosensory thalamus [ventralis caudalis (Vc)]. Median nerve poststimulus time histograms showed that single thalamic neurons fired at preferred times at intervals between 0.8 to 1.2 ms that were synchronous with the VFOs, although the neurons fired only once or a few times per trial. In the STN, low-amplitude SEPs with VFOs were observed at a latency similar to the thalamic SEPs. The VFOs from STN probably represent volume conduction, possibly from the medial lemniscus. We conclude that the thalamic VFOs are generated within Vc and that they induce time-locked firing in a network of neurons.