Noninvasive Detection of Motor-Evoked Potentials in Response to Brain Stimulation Below the Noise Floor-How Weak Can a Stimulus Be and Still Stimulate.

Goetz, SM

Li, Z

Peterchev, AV

2023-08-25T08:19:56Z

2023-08-25T08:19:56Z

2018-07

2023-08-25T08:19:56Z

Motor-evoked potentials (MEP) are one of the most important responses to brain stimulation, such as supra-threshold transcranial magnetic stimulation (TMS) and electrical stimulation. The understanding of the neurophysiology and the determination of the lowest stimulation strength that evokes responses requires the detection of even smallest responses, e.g., from single motor units, but available detection and quantization methods are rather simple and suffer from a large noise floor. The paper introduces a more sophisticated matched-filter detection method that increases the detection sensitivity and shows that activation occurs well below the conventional detection level. In consequence, also conventional threshold definitions, e.g., as 50 μV median response amplitude, turn out to be substantially higher than the point at which first detectable responses occur. The presented method uses a matched-filter approach for improved sensitivity and generates the filter through iterative learning from the presented data. In contrast to conventional peak-to-peak measures, the presented method has a higher signal-to-noise ratio (≥14 dB). For responses that are reliably detected by conventional detection, the new approach is fully compatible and provides the same results but extends the dynamic range below the conventional noise floor. The underlying method is applicable to a wide range of well-timed biosignals and evoked potentials, such as in electroencephalography.

2375-7477

2694-0604

https://hdl.handle.net/10161/28783

eng

IEEE

Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference

10.1109/embc.2018.8512765

Brain

Humans

Electroencephalography

Electric Stimulation

Evoked Potentials, Motor

Transcranial Magnetic Stimulation

Noninvasive Detection of Motor-Evoked Potentials in Response to Brain Stimulation Below the Noise Floor-How Weak Can a Stimulus Be and Still Stimulate.

Journal article

Peterchev, AV|0000-0002-4385-065X

2687

2690

Duke

Pratt School of Engineering

School of Medicine

Clinical Science Departments

Biomedical Engineering

Electrical and Computer Engineering

Psychiatry & Behavioral Sciences

Institutes and Provost's Academic Units

University Institutes and Centers

Duke Institute for Brain Sciences

Initiatives

Nicholas Institute for Energy, Environment & Sustainability

Neurosurgery

Nicholas Institute for Energy, Environment & Sustainability

Psychiatry & Behavioral Sciences, Behavioral Medicine & Neurosciences

Published

2018