What Causes Poor Memory While Suffering From High Potassium Levels?

I have noticed that my mom doesn t remember things the way she did before. We talked about it, she went to see her doctor, and instead, they told her that she had high potassium levels (she didn t explain much). I did some research and found that an unbalanced sodium and potassium level may interfere with neurons functions, which may stop sendihg information perhaps in the brain and people may forget things. My question is, whether or not my conclusions are truth, how is this peson likely to suffer a worsening condition based on the fact that she does have high potassium levels? And, is there a way to reduce this?