Fig. 1

Experimental design. Twenty-one male patients attended three sessions, where the first session consisted of a clinical and neuropsychological screening and mock scanner familiarisation; during the second session baseline MRI measurements were collected and following this, GONB treatment was administered; the third sessions served as a follow up visit, where MRI measurements were collected once again. In addition, PCASL and structural data were acquired from a group of seven matched healthy controls, using identical pulse sequence in the same scanner, to permit further comparisons. All three visits were completed within a time window of approximately 30 days