A New Approach for Creating Customizable Cytoarchitectonic Probabilistic Maps without a Template

Abstract

Abstract. We present a novel technique for creating template-free probabilistic maps of the cytoarchitectonic areas using a groupwise registration. We use the technique to transform 10 human post-mortem structural MR data sets, together with their corresponding cytoarchitectonic information, to a common space. We have targeted the cytoarchitectonically defined subregions of the primary auditory cortex. Thanks to the templatefree groupwise registration, the created maps are not macroanatomically biased towards a specific geometry/topology. The advantage of the groupwise versus pairwise registration in avoiding such anatomical bias is better revealed in studies with small number of subjects and a high degree of variability among the individuals such as the post-mortem data. A leave-oneout cross-validation method was used to compare the sensitivity, specificity and positive predictive value of the proposed and published maps. We observe a significant improvement in localization of cytoarchitectonically defined subregions in primary auditory cortex using the proposed maps. The proposed maps can be tailored to any subject space by registering the subject image to the average of the groupwise-registered post-mortem images.

Differential activity in Heschl's gyrus between deaf and hearing individuals is due to auditory deprivation rather than language modality

“…Area Te1.0 of Heschl's gyrus was defined using the cytoarchitectonic maps generated by Tahmasebi et al (2009), based on those produced by Morosan et al (2001). Briefly, Tahmasebi et al (2009) warped the 10 post-mortem brains and corresponding cytoarchitectonic information of Morosan et al (2001) into SPM's standard MNI template.…”

“…Briefly, Tahmasebi et al (2009) warped the 10 post-mortem brains and corresponding cytoarchitectonic information of Morosan et al (2001) into SPM's standard MNI template. This procedure resulted in cytoarchitectonic definitions in a standard space with higher specificity and less overlap with surrounding regions.…”

Localizing the human primary auditory cortex in vivo using structural MRI

“…Future validations must determine whether such an approach is more precise than using probability maps defined in post-mortem data(e.g. Fischl et al, 2008; Tahmasebi et al, 2009). To use this method for single subject delineation of the PAC area from neighboring secondary cortex, the data must be improved e.g.…”

“…However, the precision of the location of cortical brain areas, which have been defined in only a few brains, is limited because of the large anatomical differences between subjects. A current approach to overcome this problem is to use surface–based alignment of the cortical folding patterns (Fischl et al,2008) or template-free registration (Tahmasebi et al, 2009) in conjunction with probability maps that are based on newly defined architectonic properties of cortical areas in ten different brains (Mazziotta et al, 2001; Zilles et al, 2002). The results suggest that cortical folds are much better predictors of the cytoarchitectonically defined regions than had been previously thought.…”

Effects of Aging and Adult-Onset Hearing Loss on Cortical Auditory Regions

“…Post-mortem cytoarchitectonic analysis has revealed three distinct areas in Heschl's gyrus (from postero-medial to antero-lateral): Te1.1, Te1.0, and Te1.2. Based on its granularity, Te1.0 is the most likely human homolog of the primary auditory cortex (Morosan et al, 2001 ; Tahmasebi et al, 2009 ; Hackett, 2011 ). The fact that these cytoarchitectonic definitions bypass auditory stimulation for the definition of functional areas, which can be complicated or not possible in participants with auditory deficits, have made these cytoarchitectonic maps popular in the study of hearing loss in humans.…”