Track topics on Twitter Track topics that are important to you
: One limitation with cochlear implants is the difficulty stimulating spatially discrete spiral ganglion cell groups because of electrode interactions. Multipolar electrodes have improved on this some, but also at the cost of much higher device power consumption. Recently, it has been shown that spatially selective stimulation of the auditory nerve is possible with a mid-infrared laser aimed at the spiral ganglion via the round window. However, these neurons must be driven at adequate rates for optical radiation to be useful in cochlear implants. We herein use single-fiber recordings to characterize the responses of auditory neurons to optical radiation. STUDY
: In vivo study using normal-hearing adult gerbils.
: Two diode lasers were used for stimulation of the auditory nerve. They operated between 1.844 μm and 1.873 μm, with pulse durations of 35 μs to 1,000 μs, and at repetition rates up to 1,000 pulses per second (pps). The laser outputs were coupled to a 200-μm-diameter optical fiber placed against the round window membrane and oriented toward the spiral ganglion. The auditory nerve was exposed through a craniotomy, and recordings were taken from single fibers during acoustic and laser stimulation.
: Action potentials occurred 2.5 ms to 4.0 ms after the laser pulse. The latency jitter was up to 3 ms. Maximum rates of discharge averaged 97 ± 52.5 action potentials per second. The neurons did not strictly respond to the laser at stimulation rates over 100 pps.
: Auditory neurons can be stimulated by a laser beam passing through the round window membrane and driven at rates sufficient for useful auditory information. Optical stimulation and electrical stimulation have different characteristics; which could be selectively exploited in future cochlear implants. Laryngoscope, 2010.
Department of Surgery, ENT Section, Walter Reed Army Medical Center, Washington, DC.
This article was published in the following journal.
Name: The Laryngoscope
To determine the proportion of nerve fibers in the hypogastric nerve (HGN) and pelvic splanchnic nerve (PSN), small tissue strips of the HGN and PSN from 12 donated elderly cadavers were examined hist...
Primary motor cortex (M1) excitability can be assessed using transcranial magnetic stimulation (TMS) and can be modulated by a conditioning electrical stimulus delivered to a peripheral nerve prior to...
Functional recovery after peripheral nerve injury remains a tough problem at present. Specifically, a type of glial cell exists in peripheral nerves that promotes axonal growth and myelin formation an...
As it might lead to less discomfort, magnetic nerve stimulation (MNS) is increasingly used as an alternative to electrical stimulation methods. Yet, MNS and electrical nerve stimulation (ENS) and elec...
Combination of ultrasound and nerve stimulation technique could be useful under several conditions. Nerve stimulation canvarify the position of the nerve in case of bad preconditions during ultrasound...
The purpose of the study is to determine whether a particular type of nerve fibers, A-delta fibers, can be tested in an Electromyography (EMG) lab on a routine basis. Normal, healthy volun...
The goal of this study is to investigate the influence of transcutaneous vagus nerve stimulation 1. on the noradrenergic system in the brain and 2. on memory, in healthy volunteers. ...
Transcranial magnetic stimulation (TMS) involves the use of magnetic fields to non-invasively stimulate the brain. Studies overseas have suggested this may be an effective and safe treatme...
The purpose of this study is to evaluate the defecatory function when nerve fibers around the inferior mesenteric artery(IMA) and left colic artery(LCA) are preserved(so called low ligatio...
Patients with refractory epilepsy who are candidates for a treatment with vagus nerve stimulation will be prospectively randomized into 3 arms with different vagus nerve stimulation paradi...
A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the unmyelinated nerve fibers are small. The axons to SCHWANN CELLS ratio is greater in the unmyelinated nerve fibers than that in the myelinated fiber (NERVE FIBERS, MYELINATED) which is 1:1. Usually several axons are surrounded by a single Schwann cell in the unmyelinated nerve fibers. Therefore, each unmyelinated fiber is not completely covered by the MYELIN SHEATH formed by the Schwann cell. Unmyelinated nerve fibers conduct impulses at low velocities. They represent the majority of peripheral sensory and autonomic fibers. They are also found in the spinal cord and brain.
A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the myelinated nerve fibers are completely encased in a MYELIN SHEATH. They are fibers of relatively large and varied diameters. Their NEURAL CONDUCTION rates are faster than those of the unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED). Myelinated nerve fibers are present in somatic and autonomic nerves.
The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.
The nerve husk. The outermost part of the MYELIN SHEATH covering a myelinated nerve fiber (NERVE FIBERS, MYELINATED) or a bundle of unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED).
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the central nervous system.
Latest News Clinical Trials Research Drugs Reports Corporate
Hearing, auditory perception, or audition is the ability to perceive sound by detecting vibrations, changes in the pressure of the surrounding medium through time, through an organ such as the ear. Sound may be heard through solid, liquid, or gaseous mat...