Discussion and Conclusions

This study demonstrates that with high angular and spatial resolution diffusion imaging, the amygdala can be parceled into three subflelds. The automated clustering uses only microstructural information within the amygdala and does not require prior knowledge of histology or cortical functional projections of amygdaloid subnuclei. The physical locations of the three subflelds infer three subnuclei including lateral, basolateral, and centromedial nuclei. However, further study is warranted to validate their cortical projections by incorporating dMRI tractography to link each cluster to functionally relevant cortical regions and to compare with histologically defined subnuclei.

Acknowledgements Supported in part by Dartmouth Synergy, Indiana Alzheimer Disease Center pilot grant, NIH R01 MH080716, R01 EB022574, R01 LM011360, R01 AG19771 and P30 AG10133.


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