Dear Matthew and others,
Your summary doesn't seem to capture the essence of the discussion, as far
as I've been following. (Well, maybe point 3 about the meta-analysis, but
clearly not the first two.) I would summarize the essence of the
discussion as follows.
1) The thresholded maps are useful for demonstrating reliable effects free
of subjective bias, but care must be used in their description and
interpretation to avoid misleading uncritical readers who don't understand
the limitations of the statistical approach.
2) There may be important additional information to be derived from the
unthresholded maps, which should be considered in interpreting results.
The debate appears to be whether the responsibility for viewing and
interpreting these maps should lie in the hands of the researcher, the
manuscript editor / reviewers, or the reader of the published
manuscripts. I prefer to leave this in the hands of the
researcher; hopefully, results from other labs would disconfirm
inappropriate conclusions reached by unethical, incompetent or
short-sighted researchers.
Doug Burman
>I thought I'd also throw in a few replies, and also summarize where I
>think we've got to...
>
>Assertion 1) The thresholded map (e.g. significant areas for condition
>A > condition B) is not useful for localization, because it can't tell
>you if the activation was specific to these areas or not.
>
>Assertion 2) The continuous map does a better job of localization than
>the thresholded map (which does a very bad job), because the
>continuous map shows you the level of activity across the whole brain
>
>Then the more minor points:
>
>Assertion 3) The continuous map does a much better job for meta-analysis.
>
>I might be wrong, but I think we all basically agree on these points
>in principle?
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