You can try MIND diet, Mediterranean-DASH Intervention for Neurodegenerative Delay Diet.
This diet helps recude dementia and the decline in brain health.
The MIND Diet includes:
Green, leafy vegetables and non-starchy vegetables;
Berries like blueberries, raspberries, blackberries;
Whole grains like oatmeal, quinoa, brown rice, whole-wheat pasta;
Fish like salmon, sardines, trout, tuna, mackerel;
Bean like lentils, soybeans;
Wine (no more than 1 glass/day).
There are also foods that should be avoided:
Butter and margarine;
Pastries and sweets.