JSM 2005 - Toronto

Abstract #304479

This is the preliminary program for the 2005 Joint Statistical Meetings in Minneapolis, Minnesota. Currently included in this program is the "technical" program, schedule of invited, topic contributed, regular contributed and poster sessions; Continuing Education courses (August 7-10, 2005); and Committee and Business Meetings. This on-line program will be updated frequently to reflect the most current revisions.

To View the Program:
You may choose to view all activities of the program or just parts of it at any one time. All activities are arranged by date and time.



The views expressed here are those of the individual authors
and not necessarily those of the ASA or its board, officers, or staff.


The Program has labeled the meeting rooms with "letters" preceding the name of the room, designating in which facility the room is located:

Minneapolis Convention Center = “MCC” Hilton Minneapolis Hotel = “H” Hyatt Regency Minneapolis = “HY”

Back to main JSM 2005 Program page



Legend: = Applied Session, = Theme Session, = Presenter
Activity Number: 473
Type: Topic Contributed
Date/Time: Thursday, August 11, 2005 : 8:30 AM to 10:20 AM
Sponsor: Biometrics Section
Abstract - #304479
Title: Maximizing Power with Arterial Spin Labeling fMRI
Author(s): Jeanette Mumford*+ and Luis Hernandez-Garcia and Thomas Nichols
Companies: University of Michigan and University of Michigan and University of Michigan
Address: , Ann Arbor, MI, 48109-2029, United States
Keywords: arterial spin label ; autocorrelation function modeling
Abstract:

Functional Magnetic Resonance Imaging (fMRI) is a method for measuring human brain activity. Typically, fMRI uses the blood oxygen level-dependent (BOLD) effect, a nonquantitative method where signal changes are attributable to changes in blood flow, blood volume, and oxygen metabolism. We consider a relatively new quantitative fMRI method: blood flow imaging with arterial spin labeling (ASL). ASL measures blood flow using magnetically labeled arterial blood as a tracer, and the data consists of alternating control images (with no magnetic label) and labeled images. The subtraction of the control/label pairs creates length-N/2 time series. While the original length-N time series have appreciable autocorrelation, the differencing process tends to whiten the data, and the length-N/2 time series are assumed to have iid errors. We propose that, instead of differencing the data, the differencing should be built into the model and the length-N data should be modeled directly. In preliminary work, we found that modeling all of the data results in marked increase in precision (24% decrease in stdev). ACF modeling and whitening will improve the precision even further.


  • The address information is for the authors that have a + after their name.
  • Authors who are presenting talks have a * after their name.

Back to the full JSM 2005 program

JSM 2005 For information, contact jsm@amstat.org or phone (888) 231-3473. If you have questions about the Continuing Education program, please contact the Education Department.
Revised March 2005