3. Investigators will assess scalp to identify involved, pruritic sites along EEG lead axis T3-O1 or, secondarily, along EEG lead axis C3 to Pz. EEG testing is a standard non-invasive neurologic test in which scalp electrodes are placed in well-defined and specified positions on the scalp. We will not be doing an EEG or using electrodes. We are simply using the anatomic landmarks specified for EEG placement to allow uniform selection of scalp areas to test and biopsy.