Study of neurovascular coupling in humans via simultaneous magnetoencephalography and diffuse optical imaging acquisition

Neuroimage. 2009 Jul 1;46(3):624-32. doi: 10.1016/j.neuroimage.2009.03.008. Epub 2009 Mar 12.

Abstract

By combining diffuse optical imaging (DOI) and magnetoencephalography (MEG) we investigate neurovascular coupling non-invasively in human subjects using median-nerve stimulation. Previous fMRI studies have shown a habituation effect in the hemodynamic blood oxygen level-dependent (BOLD) response for stimulation periods longer than 2 s. With DOI and MEG we can test whether this effect in hemodynamic response can be accounted for by a habituation effect in the neural response. Our experimental results show that the habituation effect in the hemodynamic response is stronger than that in the earliest cortical neural response (N20). Using a linear convolution model to predict hemodynamic responses we found that including late neural components (> or = 30 ms) improves the prediction of the hemoglobin response. This finding suggests that in addition to the initial evoked-response deflections related to the talamic afferent input, later cortical activity is needed to predict the hemodynamic response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Brain / blood supply
  • Brain / physiology*
  • Cerebrovascular Circulation / physiology*
  • Computer Simulation
  • Diffusion Magnetic Resonance Imaging / methods*
  • Evoked Potentials, Somatosensory / physiology*
  • Female
  • Habituation, Psychophysiologic / physiology
  • Humans
  • Magnetoencephalography / methods*
  • Male
  • Models, Neurological
  • Oxygen Consumption / physiology*
  • Somatosensory Cortex / physiology*
  • Young Adult