Blood volume and hemoglobin oxygenation response following electrical stimulation of human cortex. Academic Article uri icon

Overview

abstract

  • Our understanding of perfusion-based human brain mapping techniques relies on a detailed knowledge of the relationship between neuronal activity and cerebrovascular hemodynamics. We performed optical imaging of intrinsic signals at wavelengths sensitive to total hemoglobin (Hbt; which correlate with cerebral blood volume (CBV)) and deoxygenated hemoglobin (Hbr) directly in humans during neurosurgical operations and investigated the optical signals associated with bipolar cortical stimulation at a range of amplitudes. Cortical stimulation elicited a rapid focal increase in Hbr (initial dip) in all subjects. An equally rapid increase in Hbt (<200 ms), with a slightly higher signal-to-noise ratio, was also highly localized for <2 s in spite of the non-columnar nature of the stimulus, after which the signal spread to adjacent gyri. A later decrease in Hbr (>3 s), which is relevant to the blood oxygen level dependent (BOLD) signal, was poorly localized. Increasing the stimulus amplitude elicited a linear increase in the area of the optical signal for Hbt and the initial dip but not the late decrease in Hbr, and a nonlinear increase in optical signal amplitude with a plateau effect for initial dip, Hbt and late decrease in Hbr.

publication date

  • February 15, 2006

Research

keywords

  • Blood Volume
  • Cerebral Cortex
  • Image Enhancement
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Angiography
  • Magnetic Resonance Imaging
  • Oxygen
  • Oxyhemoglobins

Identity

Scopus Document Identifier

  • 33646589720

Digital Object Identifier (DOI)

  • 10.1016/j.neuroimage.2005.11.030

PubMed ID

  • 16480899

Additional Document Info

volume

  • 31

issue

  • 1