Brain Topography

, Volume 7, Issue 1, pp 3–8

Significance probability mapping: The final touch int-statistic mapping

Authors

  • Farid Hassainia
    • Centre d'étude du sommeilHôpital du Sacré-Coeur
    • Centre d'étude du sommeil, Hôpital du Sacré-Coeur and Dept. PsychiatrieUniversité de Montréal
  • Dominique Petit
    • Centre d'étude du sommeilHôpital du Sacré-Coeur
    • Centre d'étude du sommeil, Hôpital du Sacré-Coeur and Dept. PsychiatrieUniversité de Montréal
  • Jacques Montplaisir
    • Centre d'étude du sommeilHôpital du Sacré-Coeur
    • Centre d'étude du sommeil, Hôpital du Sacré-Coeur and Dept. PsychiatrieUniversité de Montréal
Article

DOI: 10.1007/BF01184832

Cite this article as:
Hassainia, F., Petit, D. & Montplaisir, J. Brain Topogr (1994) 7: 3. doi:10.1007/BF01184832

Summary

Significance Probability Mapping (SPM), based on Student'st-statistic, is widely used for comparing mean brain topography maps of two groups. The map resulting from this process represents the distribution oft-values over the entire scalp. However,t-values by themselves cannot reveal whether or not group differences are significant. Significance levels associated with a fewt-values are therefore commonly indicated on map legends to give the reader an idea of the significance levels oft-values. Nevertheless, a precise significance level topography cannot be achieved with these few significance values. We introduce a new kind of map which directly displays significance level topography in order to relieve the reader from converting multiplet-values to their corresponding significance probabilities, and to obtain a good quantification and a better localization of regions with significant differences between groups. As an illustration of this type of map, we present a comparison of EEG activity in Alzheimer's patients and age-matched control subjects for both wakefulness and REM sleep.

Key words

EEG Brain mapping Student'st-statistic Significance probability mapping Alzheimer's disease

Copyright information

© Human Sciences Press, Inc. 1994