Measurement of pharyngeal sensory cortical processing: technique and physiologic implications

<p>Abstract</p> <p>Background</p> <p>Dysphagia is a major complication of different diseases affecting both the central and peripheral nervous system. Pharyngeal sensory impairment is one of the main features of neurogenic dysphagia. Therefore an objective technique to examine the cortical processing of pharyngeal sensory input would be a helpful diagnostic tool in this context. We developed a simple paradigm to perform pneumatic stimulation to both sides of the pharyngeal wall. Whole-head MEG was employed to study changes in cortical activation during this pharyngeal stimulation in nine healthy subjects. Data were analyzed by means of synthetic aperture magnetometry (SAM) and the group analysis of individual SAM data was performed using a permutation test.</p> <p>Results</p> <p>Our results revealed bilateral activation of the caudolateral primary somatosensory cortex following sensory pharyngeal stimulation with a slight lateralization to the side of stimulation.</p> <p>Conclusion</p> <p>The method introduced here is simple and easy to perform and might be applicable in the clinical setting. The results are in keeping with previous findings showing bihemispheric involvement in the complex task of sensory pharyngeal processing. They might also explain changes in deglutition after hemispheric strokes. The ipsilaterally lateralized processing is surprising and needs further investigation.</p

Analytical evaluation of dose measurement of critical accident at SILENE (Contract research)

Institute for Radioprotection and Nuclear Safety (IRSN) and the OECD Nuclear Energy Agency (NEA) jointly organized SILENE Accident Dosimetry Intercomparison Exercise to intercompare the dose measurement systems of participating countries. Each participating country carried out dose measurements in the same irradiation field, and the measurement results were mutually compared. The participated in the exercise to measure the doses of gamma rays and neutron from SILENE by using thermoluminescence dosimeters (TLD's) and an alanine dosimeter. In this examination, the derived evaluation formulae for obtaining a tissue-absorbed dose from measured value (ambient dose equivalent) of TLD for neutron. We reported the tissue-absorbed dose computed using this evaluation formula to OECD/NEA. TLD's for neutron were irradiated in the TRACY facility to verify the evaluation formulae. The results of TLD's were compared with the calculations of MCNP and measurements with alanine dose meter. We found that the ratio of the dose by the evaluation formula to the measured value by the alanine dosimeter was 0.94 and the formula agreed within 6%. From examination of this TRACY, we can conclude that the value reported to OECD/NEA has equivalent accuracy

The Measurement for Movement-Related Fields Averaged By Using the Force

Introduction When we measure movement-related MEGs such as movement-related field (MEF) and motor field (MF), electromyogram (EMG) obtained from corresponding muscles has been used as a trigger signal for the alignment of averaging MEGs [1,2]. However, the latency of EMG signals is often distributed inconsistently, ranging from 30msec to 60msec and this fluctuation sometimes makes difficult to analyze the temporal structure of movement-related MEGs [8]. Using signals of the force sensitive register (FSR) may be an alternate approach for a more stable latency fluctuation. FSR has been used to measure the applied force in the ergonomics/biomechanics research area owing to its direct and quick responses [3]. Therefore, it is not hard to imagine that the temporal patterns to illustrate the relationship between force intensity and MEG activity in a sensorimotor area can be clarified. With regard to isometric force exertion, there was a correlation between the force intensity and the int

Dynamic Range for Bone Conduction Ultrasound

Introduction Since Gavreau [1] reported that ultrasound could be perceived by bone conduction, controversial discussions have surrounded the concept of the auditory perception of ultrasound. Particular attention has been paid to its perception mechanism and to whether or not the profoundly hearingimpaired can detect ultrasound and discriminate ultrasound modulated by different speech sounds. Consideration is being given to the possibility of using ultrasound hearing aids as an alternative to cochlear implant. Pertaining to the peripheral mechanism of ultrasound perception, the following hypotheses were suggested by Dieroff and Ertelsu [2]. 1) Ultrasonic perception as a result of inadequate stimulation of particular sections of the hearing system [3]. 2) Ultrasonic perception as a result of adequate stimulation of particular sections of the hearing system. The second hypothesis was classified into two categories: the existence of rudimentary ultrasonic receptors [4,5] and the generati