A method for functional magnetic resonance imaging (fMRI) uses
steady-state free precession (SSFP) to image changes in blood oxygenation
between two time periods. A center frequency of the SSFP sequence is
placed between the different resonant frequencies for oxyhemoglobin and
deoxyhemoglobin whereby the signals have a phase difference of
180.degree. and tend to cancel. By repeating the SSFP imaging sequence at
different times, the difference in the measured signals provides a
measure of change in oxyhemoglobin. RF flip angle of the SSFP sequence is
chosen to maximize signal level in the frequency range from that of water
in the presence of oxyhemoglobin and that of water in the presence of
deoxyhemoglobin.