jcem.endojournals.org/cgi/conten … /88/7/3064
“The study demonstrated that testosterone replacement enhanced cerebral perfusion in midbrain and superior frontal gyrus (Brodman area 8) at 3–5 wk of treatment. At 12–14 wk the study continued to show increased perfusion in midbrain in addition to the appearance of a new activated region in the midcingulate gyrus (Brodman area 24). The results of this study provide objective evidence that testosterone and /or its metabolites increased cerebral perfusion in addition to the improvement in cognitive function.”