The cognitive impact of wealth has been pretty well studied, and there is already a very good population being studied for this - farmers in some places are pre

The cognitive impact of wealth has been pretty well studied, and there is already a very good population being studied for this - farmers in some places are pretty well off immediately after harvest/sale, and just before the next harvest, are usually back to a baseline state, or even struggling to pay bills again. Not only do they exhibit better long-term thinking when they are flush with cash, they tend be overall more cognitively capable.