There are 2 studies that match your criteria.
Criteria: Freq Range=300 kHz - 300 GHz (RF/mmW/THz),Study Type=Human / Provocation,Study Subtype=Blood Brain Barrier, Brain Circulation,Status=Ongoing

Details - Project ID 148
Lab	Medical University of Luebech, FRG
Study Design	900 MHz (GSM) exposure to humans and analysis of cerebral blood flow
Summary	(ongoing)
Citation
Details - Project ID 1242
Lab	Arhus Hospital, Denmark
Study Design	900 & 1800 MHz (GSM) mobile phone exposure and PET scan analysis of brain blood flow
Summary	PET Study of the Cerebrometabolic Effects of Nonionizing Radiation from Mobile Phones
Citation