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Updated: May 14, 2026

Stimulus-specific Cortical Visual Evoked Potential Morphological Patterns
Published on: May 12, 2019
Concentric needle jitter on voluntary activated frontalis in 20 healthy subjects
João A Kouyoumdjian1, Erik V Stålberg
1Faculdade de Medicina de São José do Rio Preto (FAMERP), Department of Neurological Sciences, Rua Luiz Antônio da Silveira 1661, 15025-020, São José do Rio Preto, São Paulo, Brazil. jaris@terra.com.br
Introduction:
Normative data for jitter parameters using a disposable concentric needle have been described in a few studies.
Methods:
Jitter, expressed as the mean consecutive difference (MCD), was measured in the frontalis muscle in 20 subjects by voluntary contraction.
Results:
Mean MCD for individual studies (20, gaussian), all potentials (400, non-gaussian), and 18th highest value (20, gaussian) were 19.9 ± 2.9 μs, 19.9 ± 6.6 μs, and 26.9 ± 4.4 μs, respectively.
Conclusion:
The suggested upper normal limit for mean MCD is 26 μs and for outliers is 36 μs.
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