Spring 2002 Seminar Series - February 5, 2002
University of Minnesota
School of Statistics
College of Liberal Arts
Mathematical and Statistical Problems Relating to Functional MRI
Martin Lindquist
University of Minnesota
(Statistics Search Candidate)
Tuesday, February 5, 2002
4:00 PM,
B10
Ford Hall
Minneapolis, East Bank Campus
Social at 3:30 PM,
300
Ford Hall
Abstract
What occurs in humans' brains when they see a picture of someone they recognize?
Recognition occurs almost immediately, but where in the brain does it take place?
Functional Magnetic Resonance Imaging (fMRI), a technique that can be used to
study mental activity in the brain, holds great promise for assisting in the
arduous task of mapping brain functions. It is also a technique where
mathematics and statistics promise to play a crucial role.
As currently used, the temporal resolution of fMRI studies are too slow to
effectively answer the questions posed above. To increase their usefulness, new
methods to accelerate the speed of fMRI studies must be introduced. In this talk,
an idea is presented for obtaining this needed acceleration, based on a
trade-off of spatial for temporal resolution, achieved by sampling only a small
fraction of the Fourier transform of the spin density and applying a prolate
spheroidal wave function filter. This is used to obtain the total activity in a
predetermined region of the brain. The fraction sampled will depend upon the
shape of the region being studied, and is carefully chosen to optimize certain
criteria.
In order to properly detect activation in the predetermined region, there is a
need for a thorough statistical analysis of the collected fMRI time series data.
Some novel approaches to analyzing fMRI data that involve the use of change-point
analysis will also be discussed.