JSM 2014 Home
Online Program Home
My Program

Abstract Details

Activity Number: 284
Type: Topic Contributed
Date/Time: Tuesday, August 5, 2014 : 8:30 AM to 10:20 AM
Sponsor: Section on Statistical Computing
Abstract #313297
Title: Clustering Approaches to Activation Detection in fMRI
Author(s): Ranjan Maitra*+ and Wei-Chen Chen
Companies: Iowa State University and University of Tennessee
Keywords: mixtures of beta distributions ; EM algorithm ; segmentation ; Bayesian Information Criterion ; missing information ; functional Magnetic Resonance Imaging
Abstract:

The past two decades have seen the development of functional Magnetic Resonance Imaging (fMRI) as a tool to noninvasively study the spatial characteristics and extent of human brain function. Preliminary statistical analysis relates the time-course MR sequences at a voxel to a stimulus and assessing significance of this relationship based on the p-values. Incorporating spatial context in the significance assessment is computationally challenging. We propose modeling the p-values as a mixture of beta distributions, while incorporating spatial context via the voxel coordinates. Parallel and accelerated Expectation-Maximization (EM) methods are used to perform computations in a practical setting and the Bayes Information Criterion (BIC) is used to determine the number of components in the best-fitting solution. The resulting segmentation is analyzed to specify common regions of activation, with promising results on simulation datasets and also on data from an fMRI study.


Authors who are presenting talks have a * after their name.

Back to the full JSM 2014 program




2014 JSM Online Program Home

For information, contact jsm@amstat.org or phone (888) 231-3473.

If you have questions about the Professional Development program, please contact the Education Department.

The views expressed here are those of the individual authors and not necessarily those of the JSM sponsors, their officers, or their staff.

ASA Meetings Department  •  732 North Washington Street, Alexandria, VA 22314  •  (703) 684-1221  •  meetings@amstat.org
Copyright © American Statistical Association.