Browsing by Subject "Peripheral Nerves"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Changes in Brain Resting-state Functional Connectivity Associated with Peripheral Nerve Block: A Pilot Study.
    (Anesthesiology, 2016-08) Melton, M Stephen; Browndyke, Jeffrey N; Harshbarger, Todd B; Madden, David J; Nielsen, Karen C; Klein, Stephen M
    BACKGROUND: Limited information exists on the effects of temporary functional deafferentation (TFD) on brain activity after peripheral nerve block (PNB) in healthy humans. Increasingly, resting-state functional connectivity (RSFC) is being used to study brain activity and organization. The purpose of this study was to test the hypothesis that TFD through PNB will influence changes in RSFC plasticity in central sensorimotor functional brain networks in healthy human participants. METHODS: The authors achieved TFD using a supraclavicular PNB model with 10 healthy human participants undergoing functional connectivity magnetic resonance imaging before PNB, during active PNB, and during PNB recovery. RSFC differences among study conditions were determined by multiple-comparison-corrected (false discovery rate-corrected P value less than 0.05) random-effects, between-condition, and seed-to-voxel analyses using the left and right manual motor regions. RESULTS: The results of this pilot study demonstrated disruption of interhemispheric left-to-right manual motor region RSFC (e.g., mean Fisher-transformed z [effect size] at pre-PNB 1.05 vs. 0.55 during PNB) but preservation of intrahemispheric RSFC of these regions during PNB. Additionally, there was increased RSFC between the left motor region of interest (PNB-affected area) and bilateral higher order visual cortex regions after clinical PNB resolution (e.g., Fisher z between left motor region of interest and right and left lingual gyrus regions during PNB, -0.1 and -0.6 vs. 0.22 and 0.18 after PNB resolution, respectively). CONCLUSIONS: This pilot study provides evidence that PNB has features consistent with other models of deafferentation, making it a potentially useful approach to investigate brain plasticity. The findings provide insight into RSFC of sensorimotor functional brain networks during PNB and PNB recovery and support modulation of the sensory-motor integration feedback loop as a mechanism for explaining the behavioral correlates of peripherally induced TFD through PNB.
  • Thumbnail Image
    ItemOpen Access
    Fully implantable neural recording and stimulation interfaces: Peripheral nerve interface applications.
    (Journal of neuroscience methods, 2020-03) Deshmukh, Ashlesha; Brown, Logan; Barbe, Mary F; Braverman, Alan S; Tiwari, Ekta; Hobson, Lucas; Shunmugam, Sudha; Armitage, Oliver; Hewage, Emil; Ruggieri, Michael R; Morizio, James

    Background

    Peripheral nerve interfacing has many applications ranging from investigation of neural signals to therapeutic intervention for varied diseases. This need has driven technological advancements in the field of electrode arrays and wireless systems for in-vivo electrophysiological experiments. Hence we present our fully implantable, programmable miniaturized wireless stimulation and recording devices.

    New method

    The method consists of technological advancements enabling implantable wireless recording up to 128 channels with a sampling rate of 50Khz and stimulation up to ±4 mA from 15 independent channels. The novelty of the technique consists of induction charging cages which enables freely moving small animals to undergo continuous electrophysiological and behavioral studies without any impediments. The biocompatible hermetic packaging technology for implantable capsules ensures stability for long-term chronic studies.

    Results

    Electromyographs wirelessly recorded from leg muscles of a macaque and a rat using implantable technology are presented during different behavioral task studies. The device's simultaneous stimulation and recording capabilities are reported when interfaced with the vagus and pelvic nerves.

    Comparison with existing method(s)

    The wireless interfacing technology has a large number of recording and stimulating channels without compromising on the signal quality due to sampling rates or stimulating current output capabilities. The induction charging technology along with transceiver and software interface allows experiments on multiple animals to be carried out simultaneously.

    Conclusions

    This customizable technology using wireless power transmission, reduced battery size, and miniaturized electronics has paved way for a robust, fully implantable, hermetic neural interface system enabling the study of bioelectronic medical therapies.