In reply
Fox et al raise several issues—some of valid concern. Since Fox and Ingham were provided with extensive documentation on our research (including the studies in question) in a 1990 visit to our laboratories, they are better informed than the average reader. They have reviewed materials and data not yet in publication which address their concerns and demonstrate that these pose no substantial threat to the validity of our findings. While much of this response to their letter will be redundant to Fox et al, we appreciate an opportunity to address these issues in this broader, public forum. We will consider issues in the order in which they were raised by Fox et al: (1) absolute flow findings; (2) relative flow findings; and (3) other methodologic concerns.Fox et al assert that, "the most important finding of the regional cerebral blood flow (rCBF) data in stuttering is the global