Nuclear magnetic resonance (NMR) proton density images of the human brain have been made by the FONAR method. Spin-lattice relaxation times, T1, of water hydrogen protons have been determined at random positions within frontal and temporal regions of the human brain. The primary purpose of this ongoing research is to accumulate a large data base of normal T1 values for water protons in normal human brain tissue. Our experience to date includes 31 measurements on 18 volunteer subjects, and the mean value +/- standard deviation is 215 +/- 42 msec. In addition, two metastatic lesions of the brain were studied and found to have T1 values longer than those for normal brain tissue.