英语翻译

英语翻译
问：能力变化的感觉呢,还是感觉能力的变化呢.、或者none of the above.请提供更好的翻译.
原句：To these indirect presumptions that our sensations,following the mutations of our capacity for feeling,are always undergoing an essential change,must be added another presumption,based on what must happen in the brain.