Statistical parametric mapping

It may alternatively refer to software created by the Wellcome Department of Imaging Neuroscience at University College London to carry out such analyses.

To filter out these random effects, and to highlight the areas of activity linked specifically to the process under investigation, statistics look for the most significant differences.

Such normalization typically involves translation, rotation and scaling and nonlinear warping of the brain surface to match a standard template.

Standard brain maps such as the Talairach-Tournoux or templates from the Montréal Neurological Institute (MNI) allow researchers from across the world to compare their results.

Images can be smoothed to make the data less noisy (similar to the 'blur' effect used in some image-editing software) by which voxels are averaged with their neighbours, typically using a Gaussian filter or by wavelet transformation.

Because many statistical tests are conducted, adjustments have to be made to control for type I errors (false positives) potentially caused by the comparison of levels of activity over many voxels.

A type I error would result in falsely assessing background brain activity as related to the task.

SPM is software written by the Wellcome Department of Imaging Neuroscience at University College London to aid in the analysis of functional neuroimaging data.