PubMed HealthSearch

PubMed · 8857312

Robust method for estimating motor unit firing-pattern statistics.

Abstract

An error-filtered estimation (EFE) algorithm for estimating the mean and standard deviation of a set of time intervals between consecutive motor unit firing times (inter-pulse intervals (IPIs)) is described. As the input IPI data are filtered and only valid IPIs are used to estimate mean and standard deviation values, the EFE algorithm provides accurate estimates even when the data defining the train of motor unit firing times are only partially complete or have several erroneous firing times. The algorithm has been evaluated using both simulated and real motor unit firing time data, and has been found to provide accurate and unbiased mean and standard deviation estimates, even when up to 70% of the IPI data are incorrect.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

D Stashuk, Y Qu. 1996. Robust method for estimating motor unit firing-pattern statistics.. https://doi.org/10.1007/bf02637022

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Primary motor cortex isolation: complete paralysis with preserved primary motor cortex.

We present a left-sided hemiplegic patient with a cerebrovascular lesion involving the medial part of the right frontal and parietal lobes and the corpus callosum, but sparing the hand area of right primary motor cortex (M1). Several studies using transcranial magnetic stimulation demonstrated functional integrity of the efferent pathways from the right M1, intact sensory afferents to M1, an impairment of transcallosal connection between the bilateral motor cortices, and reduced ipsilateral cortico-cortical inhibition within the right M1. Based on these results, we conclude that the paralysis of this patient was caused by disconnection of the intact M1 from any structures requisite for initiation of movements. The present patient also suggests the importance of various afferents to M1 in voluntary movement. We propose a term of 'primary motor cortex isolation' to designate the paralysis reported here.

Electromyography

Symmetry of normal motor and sensory nerve conduction measurements.

Nerve conduction measurements in normal subjects are assumed to be symmetric, but the normal limits of symmetry have not been determined. Full data on the limits of symmetry for commonly studied nerves are important in the clinical interpretation of nerve conduction data. We selected normal electrodiagnostic studies from archived electromyographic laboratory reports that included bilateral measurements of motor and sensory nerves. Symmetry of nerve conduction measures was confirmed, and only the median and ulnar sensory nerves had significant deviations from symmetry, supporting subclinical nerve damage in the most common dominant hand. The limits of symmetry were determined by calculating the 95th percentile for the differences between sides. For motor and sensory nerves, the range of 95th percentile limits was narrower for measures in upper extremity nerves compared to lower extremity nerves. Several reasons are offered for the wider limits of symmetry in lower extremity nerves.

Electromyography