You are right that the scalp is less than ideal. The forehead, neck, insides of the nose, and I think the upper parts of the cheek are all better for cooling the brain. I believe the best method found is one where cold dry air is pumped in one nostril and out the other to greatly increase evaporative cooling from the inside of the nose, which cools the blood moving into the brain
A water cooled forehead combined with a water cooled neck pad might work well
You are right that the scalp is less than ideal. The forehead, neck, insides of the nose, and I think the upper parts of the cheek are all better for cooling the brain. I believe the best method found is one where cold dry air is pumped in one nostril and out the other to greatly increase evaporative cooling from the inside of the nose, which cools the blood moving into the brain
A water cooled forehead combined with a water cooled neck pad might work well