Nevertheless, few patients did show memory improvements. These were the same two who reported memory recollections when the electrodes were first implanted.
Health & Medicine

Post quote

In 2008, they reported that stimulation of the hypothalamus caused vivid memory recollections for a 40-year-old man. In that case, the effect was entirely unintended and unexpected. The patient was being given DBS to try to curb his appetite (he weighed 350 pounds.)
And though the hypothalamus is involved in regulating appetite, not memory – but the fornix, a nerve bundle that passes through that area, is. It’s the main “nerve highway” connecting the hippocampus to the rest of the brain, and the hippocampus is vital for memory.