[Functional neuroimaging (fMRI, PET and MEG): what do we measure?]

Rev Med Liege. 2008 May-Jun;63(5-6):231-7.
[Article in French]

Abstract

Functional cerebral imaging techniques allow the in vivo study of human cognitive and sensorimotor functions in physiological or pathological conditions. In this paper, we review the advantages and limitations of functional magnetic resonance imaging (fMRI), positron emission tomography (PET) and magnetoencephalography (MEG). fMRI and PET measure haemodynamic changes induced by regional changes in neuronal activity. These techniques have a high spatial resolution (a few millimeters), but a poor temporal resolution (a few seconds to several minutes). Electroencephalogram (EEG) and MEG measure the neuronal electrical or magnetic activity with a high temporal resolution (i.e., milliseconds) albeit with a poorer spatial resolution (i.e., a few millimeters to one centimeter). The combination of these different neuroimaging techniques allows studying different components of the brain's activity (e.g., neurovascular coupling, electromagnetic activity) with both a high temporal and spatial resolution.

Publication types

  • English Abstract
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Brain / physiology*
  • Brain / physiopathology
  • Brain Diseases / physiopathology*
  • Humans
  • Magnetic Resonance Imaging*
  • Magnetoencephalography*
  • Positron-Emission Tomography*