کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1149371 957875 2011 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
An approximation to cluster size distribution of two Gaussian random fields conjunction with application to FMRI data
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات ریاضیات کاربردی
پیش نمایش صفحه اول مقاله
An approximation to cluster size distribution of two Gaussian random fields conjunction with application to FMRI data
چکیده انگلیسی
In brain mapping, the regions of the brain that are 'activated' by a task or external stimulus are detected by thresholding an image of test statistics. Often the experiment is repeated on several different subjects or for several different stimuli on the same subject, and the researcher is interested in the common points in the brain where 'activation' occurs in all test statistic images. The conjunction is thus defined as those points in the brain that show 'activation' in all images. We are interested in which parts of the conjunction are noise, and which show true activation in all test statistic images. We would expect truly activated regions to be larger than usual, so our test statistic is based on the volume of clusters (connected components) of the conjunction. Our main result is an approximate P-value for this in the case of the conjunction of two Gaussian test statistic images. The results are applied to a functional magnetic resonance experiment in pain perception.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Statistical Planning and Inference - Volume 141, Issue 7, July 2011, Pages 2331-2347
نویسندگان
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