Vascular transit times in calcarine cortex: Kinetic analysis of R2* changes observed using localized 1H spectroscopy

J. A. Detre, Z. Wang, M. M. Stecker, R. A. Zimmerman

Research output: Contribution to journalArticle

2 Scopus citations


A kinetic analysis of water signal intensity changes measured in human visual cortex by PRESS localized 1H spectroscopy at 500 ms resolution with light-emitting diode (LED) goggle stimulation was used to determine vascular transit times for transitions between rest and activation. Monoexponential curve fitting was used to determine both R2* values for each free induction decay and the time constants for R2* changes with activation and deactivation. Measured transit time values were in general agreement with the literature, and were significantly shorter for 'Off→On' than for 'On→Off' transitions, consistent with known alterations in blood flow with activation and deactivation. The differences in transit times between 'Off→On' and 'On→Off' also varied with stimulus frequency in accordance with known physiology. This type of analysis may provide a useful means of analyzing functional activation data and for quantitatively comparing functional activation results from differing subjects and imaging sessions.

Original languageEnglish (US)
Pages (from-to)326-330
Number of pages5
JournalMagnetic Resonance in Medicine
Issue number3
Publication statusPublished - 1995



  • H spectroscopy
  • calcarine cortex
  • functional activation
  • transit time

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

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