"Neuroimaging data" is extremely vague and nonspecific. What kind of imaging, how big are the files, and what kind of processing will you be doing on it? Are there GPU implementations of the algorithms you plan on using, and if not, do you plan on writing them? What kind of redundancies do you want in place for the storage? Whatever it is, I would recommend not getting SSD hard drives - they'll drive up the cost to insane levels for no good reason if you need any kind of big storage capacity.