A model of variability in brain stimulation evoked responses.
Abstract
The input-output (IO) curve of cortical neuron populations is a key measure of neural
excitability and is related to other response measures including the motor threshold
which is widely used for individualization of neurostimulation techniques, such as
transcranial magnetic stimulation (TMS). The IO curve parameters provide biomarkers
for changes in the state of the target neural population that could result from neurostimulation,
pharmacological interventions, or neurological and psychiatric conditions. Conventional
analyses of IO data assume a sigmoidal shape with additive Gaussian scattering that
allows simple regression modeling. However, careful study of the IO curve characteristics
reveals that simple additive noise does not account for the observed IO variability.
We propose a consistent model that adds a second source of intrinsic variability on
the input side of the IO response. We develop an appropriate mathematical method for
calibrating this new nonlinear model. Finally, the modeling framework is applied to
a representative IO data set. With this modeling approach, previously inexplicable
stochastic behavior becomes obvious. This work could lead to improved algorithms for
estimation of various excitability parameters including established measures such
as the motor threshold and the IO slope, as well as novel measures relating to the
variability characteristics of the IO response that could provide additional insight
into the state of the targeted neural population.
Type
Journal articlePermalink
https://hdl.handle.net/10161/24068Published Version (Please cite this version)
10.1109/EMBC.2012.6347467Publication Info
Goetz, SM; & Peterchev, AV (2012). A model of variability in brain stimulation evoked responses. Conference proceedings : ... Annual International Conference of the IEEE Engineering
in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society.
Conference, 2012. pp. 6434-6437. 10.1109/EMBC.2012.6347467. Retrieved from https://hdl.handle.net/10161/24068.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
Collections
More Info
Show full item recordScholars@Duke
Stefan M Goetz
Assistant Professor in Psychiatry and Behavioral Sciences
Angel V Peterchev
Associate Professor in Psychiatry and Behavioral Sciences
I direct the Brain Stimulation Engineering Lab (BSEL) which focuses on the development,
modeling, and application of devices and paradigms for transcranial brain stimulation.
Transcranial brain stimulation involves non-invasive delivery of fields (e.g., electric
and magnetic) to the brain that modulate neural activity. It is widely used as a tool
for research and a therapeutic intervention in neurology and psychiatry, including
several FDA-cleared indications. BSEL develops novel technology s
Alphabetical list of authors with Scholars@Duke profiles.

Articles written by Duke faculty are made available through the campus open access policy. For more information see: Duke Open Access Policy
Rights for Collection: Scholarly Articles
Works are deposited here by their authors, and represent their research and opinions, not that of Duke University. Some materials and descriptions may include offensive content. More info