Conduction Velocities and Their Temperature Coefficients in Sensory Nerve Fibres of Cockroach Legs

1967 ◽  
Vol 46 (1) ◽  
pp. 63-84
Author(s):  
K. M. CHAPMAN ◽  
J. H. PANKHURST
Keyword(s):  
Conduction Velocity ◽  
Periplaneta Americana ◽  
Sensory Nerve ◽  
Point Of View ◽  
Conduction Delay ◽  
Nerve Fibres ◽  
Impulse Frequency ◽  
Temperature Coefficients ◽  
Conduction Velocities ◽  
Sensory Encoding

1. Conduction velocities of individual afferent nerve fibres from tactile spines and proprioceptive campaniform sensilla have been measured in situ over the temperature range 5-42° C., in leg preparations of the cockroach Periplaneta americana. 2. Conduction velocities at 20° C. (u20) averaged 3.3±1.4 m./sec., ranging from 1.6 to 11.0 m./sec. 3. Temperature coefficients, expressed as Q10 for the interval 20-30° C., averaged 1.7±0.24, ranging from 1.3 to 2.6. 4. The length of the propagated disturbance is about 2-3 mm., and is nearly temperature-independent. 5. Fibre diameters, estimated from conduction velocity, must be about 10 µ. 6. There is no correlation between conduction velocity and distance from the sensillum to the thoracic ganglion. Conduction delays in fibres conducting within one standard deviation of mean u20 range from about 2 to 15 msec., from the most proximal to the most distal tactile spines. 7. The effect of conduction delay on temporal and spatial sensory encoding is probably unimportant from a behavioural point of view. It contributes a factor of the form exp(-sd/u) to the sensory transfer function, and may be appreciable at upper physiological frequencies of impulse frequency modulation.

scholarly journals Normative Data for Median Nerve Conduction in Healthy Young Adults from Punjab, India

2017 ◽  
Vol 08 (S 01) ◽  
pp. S083-S088
Author(s):  
Manjinder Singh ◽  
Sharat Gupta ◽  
Kamal Dev Singh ◽  
Avnish Kumar
Keyword(s):  
Median Nerve ◽  
Conduction Velocity ◽  
Nerve Conduction ◽  
Normative Data ◽  
Motor Nerve ◽  
Sensory Nerve ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Standardized Protocol ◽  
Conduction Velocities

ABSTRACT Background: Nerve conduction studies (NCSs) are essential for diagnosing various kinds of focal and diffuse neuropathies. Due to the paucity of local NCS data, electrodiagnostic laboratories in Punjab rely on values from Western and other Indian studies. Aim: This study was conducted to provide normative data for median nerve conduction parameters (motor and sensory) in Punjabi populace. Materials and Methods: A cross-sectional study was done on 290 participants (150 males and 140 females), aged 17–21 years, as per standardized protocol. The data were analyzed separately for both genders using SPSS version 20. It consisted of distal latencies and conduction velocities of motor and sensory divisions of median nerve. Student's unpaired t-test was used for statistical analysis. Results: There was no effect of gender on any of the median nerve conduction parameters. Height and weight had nonsignificant negative and positive correlation, respectively (P > 0.05), with conduction velocity in both motor and sensory median nerves. For median motor nerve, the values of distal latency and conduction velocity in males were 2.9 ± 0.16 ms and 60.25 ± 2.99 m/s, respectively, whereas, in females, they were 2.6 ± 0.43 ms and 59.83 ± 2.82 m/s. Similarly, for median sensory nerve, the latency and velocity values in males were 2.8 ± 0.56 ms and 54.81 ± 3.70 m/s, whereas, in females, they were 2.4 ± 0.33 ms and 54.56 ± 3.65 m/s, respectively. Conclusion: The data in this study compared favorably with already existing data. It would help the local electrodiagnostic laboratories in assessing the median nerve abnormalities with greater accuracy in this population subset.

Electrophysiological and Clinical Improvement in Non-Invasive Treatment of Carpal Tunnel Syndrome

2020 ◽  
Vol 20 ◽  
Author(s):  
Riccardo Marvulli ◽  
Giancarlo Ianieri ◽  
Grazia Devenuto ◽  
Marta Falcicchio ◽  
Giulia A. Gallo ◽  
...  
Keyword(s):  
Carpal Tunnel Syndrome ◽  
Sleep Quality ◽  
Conduction Velocity ◽  
Carpal Tunnel ◽  
Nerve Conduction ◽  
Nerve Conduction Velocity ◽  
Pantothenic Acid ◽  
Sensory Nerve ◽  
Sensory Nerve Conduction Velocity ◽  
Tunnel Syndrome

Background and Objective: Carpal tunnel syndrome (CTS) is the most common form of nerve entrapment. Clinically, various signs and symptoms compare due to overexposure to mechanical vibrations transmitted to the wrist bones and cartilage, resulting in compression of the sensory and motor nerve fibers of median nerve. Early symptoms include nocturnal paresthesia and electromyography reveals reduced sensory nerve conduction velocity. Aim of this study was to evaluate the efficacy of a dietary integrator composed of acetyl-L-carnitine, α-lipoic acid,quercetin, bromelain, pantothenic acid, C and B1 and B2 and B6 and B12 vitamins in patients with early (minimal) carpal tunnel syndrome. Methods: 36 patients (28 female and 8 male) with early CTS characterized by sensory nerve demyelination and inflammation of the transverse carpal ligament. Patients were divided into two groups, group A (18 patients received physical therapy) and group B (18 patients, received physical therapy and an oral integrator). Clinical (sleep quality questionnaire to measure severity of paresthesia) and neurophysiological assessment (Sensory Nerve Conduction Velocity) performed at baseline, and then at 30 and 60 days after treatment. Results: Sleep quality and Sensory Nerve Conduction Velocity data analysis show improvement in both groups at 30 and 60 days, with statistically difference between them in both time of analysis. Conclusions: In the early CTS, with sensory fibers damage, use of dietary integrator, such as Micronil Dol®, composed composed of acetyl-L-carnitine, α-lipoic acid,quercetin, bromelain, pantothenic acid, C and B1 and B2 and B6 and B12 vitamins can be effective in quick recovery of median nerve sensory.

scholarly journals Associations of cells from both innate and adaptive immunity with lower nerve conduction velocity: the Maastricht Study

2021 ◽  
Vol 9 (1) ◽  
pp. e001698
Author(s):  
Haifa Maalmi ◽  
Kristiaan Wouters ◽  
Hans H C M Savelberg ◽  
Jeroen H P M van der Velde ◽  
Jos P H Reulen ◽  
...  
Keyword(s):  
T Cells ◽  
Adaptive Immunity ◽  
Conduction Velocity ◽  
Nerve Conduction ◽  
Nerve Conduction Velocity ◽  
Essential Feature ◽  
Sensory Nerve ◽  
Linear Regression Models ◽  
Cross Sectional ◽  
Innate And Adaptive Immunity

IntroductionDistal sensorimotor polyneuropathy (DSPN) is common in people with diabetes but is also found in pre-diabetes. Peripheral nerve myelin damage, which can be assessed by reduced nerve conduction velocity (NCV), is an essential feature of DSPN. Emerging evidence indicates that the development of DSPN may involve the activation of the immune system. However, available studies have mainly investigated circulating immune mediators, whereas the role of immune cells remains unclear. Therefore, we aimed to test whether leukocyte subsets are associated with NCV.Research design and methodsThis cross-sectional study analyzed data from 850 individuals (of whom 252 and 118 had type 2 diabetes and pre-diabetes, respectively) of the Maastricht Study. NCV was measured in the peroneal and tibial motor nerves and the sural sensory nerve and summed to calculate a standardized NCV sum score. Associations between percentages of leukocyte subsets and NCV sum scores were estimated using linear regression models adjusted for demographic, lifestyle, metabolic and clinical covariates.ResultsAfter adjustment for covariates, higher percentages of basophils and CD4+ T cells were associated with lower NCV (p=0.014 and p=0.005, respectively). The percentage of CD8+ T cells was positively associated with NCV (p=0.022). These associations were not modified by glucose metabolism status (all pinteraction >0.05). No associations were found for monocytes, eosinophils, neutrophils, lymphocytes, total T cells, Treg cells and B cells.ConclusionsThe associations of basophils, CD4+ and CD8+ T cells with NCV suggest that cell types from both innate and adaptive immunity may be implicated in the development of DSPN.

scholarly journals Normal neurophysiologic parameters of the median nerve among adult healthy Sudanese population

2020 ◽  
Vol 10 (4) ◽  
pp. 136-141
Author(s):  
Mohammed Salah Elmagzoub ◽  
Ahmed Hassan Ahmed ◽  
Hussam M A Hameed
Keyword(s):  
Action Potential ◽  
Median Nerve ◽  
Conduction Velocity ◽  
Nerve Conduction ◽  
Compound Muscle Action Potential ◽  
Motor Nerve ◽  
Sensory Nerve ◽  
Peak Latency ◽  
Muscle Action Potential ◽  
Sensory Nerve Action

Background: Nerve conduction studies (NCSs) help in delineating the extent distribution of neural lesion, and the diagnosis of peripheral nerve disorders. Because normative nerve conduction parameters were not yet established in Sudan EMG laboratories, this study aims towards having our own reference values, as we are using the American and British parameters. This will allow avoiding the discrepancies that might be induced by many factors. Methods: NCSs were performed in 200 Median nerves of 100 adult healthy Sudanese subjects using standardized techniques. Results: The median SNAP (sensory nerve action potential) values were as follows: distal latency, 2.6±3 ms with a range of (2.3-2.9); peak latency, 3.5±0.5 ms (3.0-4.0); amplitude, 47.7±18.0μV (29.7-65.7); conduction velocity, 53.0±7.8 m/s (45.2-60.8). The following values were obtained for the Median nerve CMAP (compound muscle action potential) at wrist stimulation: distal latency, 3.5±0.5 ms with a range of (3.0-4.0); peak latency, 9.4± 1.0 ms (8.4-10.4); duration, 5.9±0.9 ms (5.0-6.8); amplitude, 12.3±2.5 mV (9.8-14.8); area, 43.0±10.4 mVms (32.6-53.4); conduction velocity, 63.6±6.2 m/s (57.4-69.8). The F wave was 28.4±1.8 ms (26.6-30.2). Conclusion: The overall mean sensory and motor nerve conduction parameters for the tested nerve compared favorably with the existing literature with some discrepancies that were justified.

The Response of a Proprioceptor to the Undulatory Movements of Dogfish

1969 ◽  
Vol 51 (3) ◽  
pp. 775-785 ◽  
Author(s):  
B. L. ROBERTS
Keyword(s):  
Angular Velocity ◽  
Body Wall ◽  
Maximum Velocity ◽  
The Body ◽  
Nerve Fibres ◽  
Impulse Frequency ◽  
Segmental Nerve

1. Recordings were made from segmental nerve fibres in dogfish while body-wall strips were bent sinusoidally at frequencies and angles comparable with the movements of intact fish. 2. The sensory discharge recorded from a slowly adapting mechanoreceptor in the body wall was proportional to the angular velocity and to the amplitude of the movements. 3. The receptor discharged bursts of sensory impulses during every movement cycle near to the time of maximum velocity. 4. The impulse frequency and the number of potentials in each sensory burst was dependent on the frequency of the bending movement. The number of active units depended on the angle of displacement and on the position of the receptor. 5. These experiments show that this mechanoreceptor could provide information about the frequency and the angle of bending of the body of dogfish during swimming movements.

Use of Bromphenol Blue Printing Method for Detecting Sweat on the Palm

1986 ◽  
Vol 11 (1) ◽  
pp. 125-130
Author(s):  
M. SAKURAI
Keyword(s):  
Sensory Nerve ◽  
Sweat Glands ◽  
Bromphenol Blue ◽  
Nerve Function ◽  
Nerve Fibres ◽  
Recovery Stage ◽  
Sympathetic Nerve Fibres ◽  
The Many ◽  
The One ◽  
Printing Method

Sympathetic nerve fibres innervating the sweat glands in the skin are known to accompany sensory nerve fibres closely. Examination of sudorific function, therefore, is a useful aid in making a diagnosis of severed peripheral nerve and also provides valuable information on nerve function in the recovery stage following injury and surgery such as neurorrhaphy. Among the many methods which have been used clinically, the one employing bromphenol blue is thought to be the most simple and accurate.

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