A study involving 449 older adults (50+) found that those with high blood pressure who achieved systolic blood pressure of less than 120 mm Hg ("intensive" blood pressure control) had a small but significantly lower amount of white matter lesions on their brain but a slightly greater decrease in brain volume than similar patients who achieved the current standard for healthy blood pressure of 140 mm Hg.

https://www.eurekalert.org/pub_releases/2019-08/uota-gbp081319.php

The SPRINT MIND Investigators for the SPRINT Research Group. Association of Intensive vs Standard Blood Pressure Control With Cerebral White Matter Lesions. JAMA. 2019;322(6):524–534. doi:10.1001/jama.2019.10551