ReviewThe NIH experience in first advancing fMRI

The introduction of functional MRI at NIH in 1992 was the outcome of research goals first formulated by Turner in 1983. Between 1988 and 1990, Turner worked at NIH on actively-shielded gradient coils and the implementation of EPI-based techniques, especially diffusion-weighted EPI. His work on hypoxia in cat brain in 1990 directly inspired Ken Kwong's demonstration of BOLD contrast in humans at MGH in May 1991. Turner collaborated actively with this MGH team, the first group to map entirely noninvasively human brain activity due to visual stimulation. He introduced BOLD fMRI at NIH in February 1992. This paper reviews the steps that led up to BOLD EPI, and Turner's initial applications of BOLD fMRI at NIH.

► Motivation for investigation of BOLD contrast. ► Value of EPI data acquisition. ► Detailed chronology of first experiments. ► Response of NIH neuroscientists to successful BOLD fMRI.