Perhaps this paper would be better than the videos. I posted the videos because they are easier to understand. https://onlinelibrary.wiley.com/doi/full/10.1046/j.1471-4159...
I think mercury is a major factor in many illnesses, and the root cause of mine. I did have some serious memory issues for a while, and my ability to focus was so bad that I could not watch a TV show. There are tens of thousands discussing the same kinds of symptoms and how they disappear with chelation.
I think the source of mercury exposure, duration of exposure, intensity of exposure, where the toxicity eventually settles in the body, and genetic factors all play a role in the symptoms that an individual suffers from. That is why one toxin can cause such a wide range of illnesses. The "radium girls" who were poisoned working with radium in factories is a good example of this.