Validation of brain connectivity analysis using fMRI simulation Online publication date: Fri, 16-Oct-2015
by Shamil M. Hadi; Mohammad-Reza Siadat; Abbas Babajani-Feremi
International Journal of Engineering Systems Modelling and Simulation (IJESMS), Vol. 7, No. 4, 2015
Abstract: Functional magnetic resonance imaging (fMRI) has been widely used in cognitive neuroscience. Brain connectivity analysis such as dynamic causal modelling (DCM) using fMRI has drawn increasing attention of neuroimaging researchers. However, performance of DCM under low SNR has not been explored and validated thoroughly. A reasonable question is what levels of noise can be handled by the DCM. Therefore, simulation is an appropriate methodology to address this question. We propose the Euler method to simulate fMRI signal. The results were compared to those of the SPM-generate. Some parameters estimated by DCM were significantly different. Unlike SPM-generate, DCM always converged when using signals generated by Euler method. Although DCM performed similarly in linear scenario for both methods, DCM handled higher noise levels for Euler compared to SPM-generate. The higher performance of DCM when using Euler method might be due to direct discretisation of the dynamic system of the neuronal state variables.
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Engineering Systems Modelling and Simulation (IJESMS):
Login with your Inderscience username and password:
Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.
If you still need assistance, please email subs@inderscience.com
Our Blog 
Follow us on Twitter 
Visit us on Facebook