Blurry as tremor.

The late Renaissance Dutch painter Frans Hals (1582–1666) was a master of revealing his subjects’ peculiarities. However, in the Regentesses (figure), he shows a neurologic condition—the blurred shoulder margin of the woman in the middle suggests trembling in a standing figure. Is it possible that Hals, who once amazed Van Gogh by his 27 “blacks,” borrowed a technique from double exposure photography centuries in advance to depict a fairly common (e.g., parkinsonian or essential) tremor? Or the alternative: he painted what he saw—very fast trembling, producing illusion of double shoulders— perhaps the earliest depiction of orthostatic tremor.