Sample fMRI Block Design Analysis using SPM


This tutorial describes how to analyze a simple fMRI dataset. To complete this tutorial you will need:
  1. MATLAB installed on your computer.
  2. SPM installed on your computer.
  3. Download and extract the sample dataset that includes the fMRI data (in NIfTI format), an anatomical scan (also T1) and text files that describe the timing.

Consider a simple experiment where we ask an individual to press their left hand at some timepoints, their right hand at other times, and to simply rest at other moments in time. In this situation one would expect that the left motor cortex and right cerebellum will be activated following right hand movement. This tutorial shows how to analyze this dataset. Below we provide a sample dataset from the GSU/GT Center for Advanced Brain Imaging.

The image below illustrates our study. The vertical axis shows time, in 1.92 second fMRI volumes (the picture shows the first 6 minutes). The red and green bars along the top of the image show when the individual presses their left (red) or right hand (green) - note that they press the same hand continuously for 12 seconds (a 'block' design). The red and green lines show the predicted blood flow signal for regions that are activated following left and right hand movements. Note that we expect the images to become brighter several seconds after an individual starts a task (the blood flow effect is sluggish).

[Image: Model Timecourse]

Analyzing the dataset