I am not good at recalling names, and never have been. Is my brain not working as well as it did? Is it dementia? Or does everyone have weaknesses that get progressively worse as you age?
The probability of having autism is greater for an individual if it runs in their family. This suggests hereditary factors. But what do you actually inherit? What you inherit is a predisposition for a specific development of your brain. This, together with what you experience while growing up, can lead to the development of a mild to severe form of autism.
Is a thought simply the sum total of the activity of all the neurons in the brain? No, just as a message is not simply the placement of a sequence of letters which follow the rules of grammar. How do those letters stand in relation to that message? How does the activity of neurons stand in relation to a thought? Was Descartes right, or are we our brain?
Disease can be seen as the antechamber of death.
Are there reliable tests for predicting disease? The short answer is: not for Alzheimer’s or other common diseases. Tests do exist for some specific diseases, most with known familial predispositions, such as Huntington’s disease, cystic fibrosis, Duchenne’s dystrophy and many more.