The Renyi entropy in data-driven analysis for pharmacological MRIJohn McGonigle, Majid Mirmehdi, Robin Holmes, Andrea L. Malizia, The Renyi entropy in data-driven analysis for pharmacological MRI. Joint Annual Meeting ISMRM-ESMRMB. May 2010. PDF, 609 Kbytes.
The analysis of pharmacological MRI (phMRI) traditionally depends upon the use of an appropriate input function, usually derived from blood plasma concentrations of the drug used in the experiment. There are a number of problems with this approach including the relationship between plasma and brain concentrations and the longer term effects of receptor activation. Because of this a number of data-driven approaches have been used where no model of the neural response is known a priori such as independent component analysis and wavelet cluster analysis. Here we explore the use of a measure of signal complexity known as the Renyi entropy to discover voxels of interest in a data-driven manner using a dataset known to show reduced perfusion in the hippocampus.