Affordable Access

Publisher Website

Intrasubject reliability and validity of somatosensory source localization using a large array biomagnetometer

Authors
Journal
Electroencephalography and Clinical Neurophysiology
0013-4694
Publisher
Elsevier
Publication Date
Volume
90
Issue
2
Identifiers
DOI: 10.1016/0013-4694(94)90006-x
Keywords
  • Neuromagnetic Fields
  • Somatosensory Source Localization
  • Biomagnetometer

Abstract

Abstract Neuromagnetic fields were evoked by tactile stimuli and detected with a multi-channel biomagnetometer through 72 independent repetitive measurements on a single subject. Each measurement consisted of a somatosensory evoked response (N = 256 stimuli) using a single probe placement. These fields were then analyzed for source localization using an equivalent current dipole model and demonstrated highly reliable localization. The 3 major neuromagnetic somatosensory response components peaking at 35, 65 and 110 msec all localized to the same area of cortex. The relative contributions of intrinsic brain activity, habituation, probe placement, and choice of fiduciary points for headframe determination were quantified. Intrinsic factors were found to constitute the major source of inter-measurement error. Sources localized by magnetic source imaging (MSI) appeared valid relative to neuroanatomical estimation of the central fissure on MRI. Non-invasive presurgical biomagnetic localization of somatosensory cortex produces reliable and valid functional localizations which can be of potential value in risk assessment and may provide a useful guide for invasive functional mapping.

There are no comments yet on this publication. Be the first to share your thoughts.