MEDICAL INTERPRETATIONS OF KING LEAR. Simon Russell Beale did a recent Lear in which he portrayed Lear as a victim of a particular form of dementia. In this interview by Hannah Furness in the Telegraph (Feb. 7, 2014), Beale said he studied “Lewy Body dementia” and that he used symptoms of it—such as “sudden outbursts of anger” and “hallucinations, fear, anger and a shaking hand”—in his performance.
This wikiedia essay says that Lewy bodies are clumps of protein in neurons in the brain identifiable in a post mortem. Hannah Furness says: “According to the Alzheimer’s Society, Lewy bodies accounts for as many as ten per cent of dementia cases, and involves symptoms associated with both Alzheimer’s and Parkinson’s disease.”
On the other hand, Timothy West in the interview I linked to yesterday, says that he consulted a surgeon and was told: “No, you don’t want to talk about senile dementia. What he’s got is arteriosclerosis.”
Since I have always thought that what Lear says and does can be explained by the play, I don’t think I would find a medical diagnosis to be helpful.