Yup. This is true. There was a tribe that ate the brains of the deceased elders as a form of reverence and to acquire the knowledge of those deceased. Unfortunately, it turns out that they were passing a form of ('unique') brain disease continuously through the generations with this practice. The disease was akin to something we call 'mad-cow disease' today but not the same. Anthropologists believe they have stopped this elder brain eating practice but, they're not 100% sure.
Yes, I am aware of that problem. ~"One of" the "handicaps" to cannibalism.~
~:-o