[Introduction to functional magnetic resonance]

During recent years we have seen the birth and development of a technique destined to revolutionize the world of the neurosciences, functional magnetic resonance (fMR). This new technique presents many challenges, both from the hardware point of view (little signal, relatively limited spatial and temporal resolution, artefacts, etc.) and of analysis (correction for movement, improved signal/noise ratio, statistical models used, etc.).

In this paper we review the most important aspects of fMR regarding artefacts, analysis and origin of the signal, based on the widely used BOLD contrast.

Although still at its beginnings, and in spite of aspects which need improvement, fMR appears to be a very useful tool both for clinical applications and investigation, and its use should be encouraged by normal MR imaging teams in everyday clinical practice.