Fig. 1.

Scan-rescan variability in cortical thickness during free water and water control conditions in one Rhesus macaque. Scans P1 and P2 were both acquired when the subject had unlimited access to water for at least one month, and were separated by 13 days. P3 was acquired at the end of a 24-day period of fluid control that started immediately after P2. The fluid control protocol consisted in access to 70% of free intake, 6 days a week. Regions-of-interest were chosen randomly. CT. Cortical Thickness. SMA. Supplementary Motor Area. pre-SMA. Pre-Supplementary Motor Area.*paired-t-test, p < 0.0001. Note that the difference is of small amplitude but consistent across brain regions. These results come from one subject and need to be replicated.