A Sensitivity Analysis of fMRI Balloon Model

الملخص EN

Functional magnetic resonance imaging (fMRI) allows the mapping of thebrain activation through measurements of the Blood Oxygenation Level Dependent (BOLD) contrast.

The characterization of the pathway from theinput stimulus to the output BOLD signal requires the selection of an adequate hemodynamic model and the satisfaction of some specific conditionswhile conducting the experiment and calibrating the model.

This paper,focuses on the identifiability of the Balloon hemodynamic model.

By identifiability, we mean the ability to estimate accurately the model parametersgiven the input and the output measurement.

Previous studies of the Balloon model have somehow added knowledge eitherby choosing prior distributions for the parameters, freezing some of them, orlooking for the solution as a projection on a natural basis of some vectorspace.

In these studies, the identification was generally assessed using event-related paradigms.

This paper justifies the reasons behind the need of addingknowledge, choosing certain paradigms, and completing the few existing identifiability studies through a global sensitivity analysis of the Balloon modelin the case of blocked design experiment.