Uses in Functional and Anatomical Studies

Landmark research [13-15] demonstrated that individual variability in response location —when reported using Talairach coordinates —has a standard deviation on the order of 5 mm and is similar across different brain areas [17,21], regardless of the nature of the complexity of the operation performed. That intersubject averaging gives statistically well-behaved reductions in background noise and increases in signal-to-noise ratio [16,23-25] is strong confirmation that intersubject functional variability is not large (Fig. 7, PET). These observations encouraged many laboratories to incorporate spatial normalization and image averaging in the experimental design of functional studies of the brain. It is now common practice to use Talairach coordinates in functional brain mapping studies [19]. The human BrainMap database makes use of this standardization, to record functional brain findings using Talairach coordinates [18,20,22]. Probabilistic 3D regions of interest defining location and extent of elementary mental operations in Talairach space have been reported for use in functional PET studies [21]. Talairach coordinates have been used to guide researchers to target transcranial stimulation of brain regions [40, 41]. Spatial normalization has subsequently been validated for use in high-resolution anatomical MR images [8,9,32,35,56,57],

By providing a means to standardize brain images spatially, the Talairach space has solved many of the problems associated with the "gross anatomical space". Statistical models of anatomical [10,36] and functional [21] variability are now available for use in Talairach space, providing insight for both individual and population studies of the brain. Talairach coordinates are commonly used to obtain labels for typical anatomical and functional areas from the 1988 Talairach atlas. A network-based brain-label server called the Talairach Daemon [33] automates this process by providing a hierarchical set of anatomical labels using Talairach coordinates. A variety of software packages for spatial normalization to Talairach space are available over the Internet, and many centers are using these applications to enhance their research, educational, and clinical capabilities.

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