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Dynamic causal modelling for functional near-infrared spectroscopy.

Tak S, Kempny AM, Friston KJ, Leff AP, Penny WD - Neuroimage (2015)

Bottom Line: Specifically, we present a generative model of how observed fNIRS data are caused by interactions among hidden neuronal states.Inversion of this generative model, using an established Bayesian framework (variational Laplace), then enables inference about changes in directed connectivity at the neuronal level.Using experimental data acquired during motor imagery and motor execution tasks, we show that directed (i.e., effective) connectivity from the supplementary motor area to the primary motor cortex is negatively modulated by motor imagery, and this suppressive influence causes reduced activity in the primary motor cortex during motor imagery.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London WC1N 3BG, UK. Electronic address: s.tak@ucl.ac.uk.

No MeSH data available.


Estimates of DCM parameters, including neurodynamic and hemodynamic effects. Magnitude of bar graph indicates posterior mean of each parameter, and the red error bar indicates the standard deviation (square root of posterior variance) for model 9.
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f0030: Estimates of DCM parameters, including neurodynamic and hemodynamic effects. Magnitude of bar graph indicates posterior mean of each parameter, and the red error bar indicates the standard deviation (square root of posterior variance) for model 9.

Mentions: We selected M1 and SMA for source region 1 and source region 2, task for the first input, and motor imagery for the second input. So, as an example of analysis results, B1,22 indicates that connectivity strength from SMA to M1 was reduced by motor imagery (− 0.77). This is entirely consistent with previous fMRI activation studies of this paradigm – and the notion that imagined movement calls on the same sensorimotor schemata here as executed movements – but gated at the level of the motor cortex. More details about the estimate of DCM parameters, including posterior variance, are shown in Fig. 6.


Dynamic causal modelling for functional near-infrared spectroscopy.

Tak S, Kempny AM, Friston KJ, Leff AP, Penny WD - Neuroimage (2015)

Estimates of DCM parameters, including neurodynamic and hemodynamic effects. Magnitude of bar graph indicates posterior mean of each parameter, and the red error bar indicates the standard deviation (square root of posterior variance) for model 9.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4401444&req=5

f0030: Estimates of DCM parameters, including neurodynamic and hemodynamic effects. Magnitude of bar graph indicates posterior mean of each parameter, and the red error bar indicates the standard deviation (square root of posterior variance) for model 9.
Mentions: We selected M1 and SMA for source region 1 and source region 2, task for the first input, and motor imagery for the second input. So, as an example of analysis results, B1,22 indicates that connectivity strength from SMA to M1 was reduced by motor imagery (− 0.77). This is entirely consistent with previous fMRI activation studies of this paradigm – and the notion that imagined movement calls on the same sensorimotor schemata here as executed movements – but gated at the level of the motor cortex. More details about the estimate of DCM parameters, including posterior variance, are shown in Fig. 6.

Bottom Line: Specifically, we present a generative model of how observed fNIRS data are caused by interactions among hidden neuronal states.Inversion of this generative model, using an established Bayesian framework (variational Laplace), then enables inference about changes in directed connectivity at the neuronal level.Using experimental data acquired during motor imagery and motor execution tasks, we show that directed (i.e., effective) connectivity from the supplementary motor area to the primary motor cortex is negatively modulated by motor imagery, and this suppressive influence causes reduced activity in the primary motor cortex during motor imagery.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London WC1N 3BG, UK. Electronic address: s.tak@ucl.ac.uk.

No MeSH data available.