The evolution of the patient’s work is striking, with increased similarity between the model and the produced work with medication increase. It is not clear that this was due to an increase in the patient’s creativity, even though an increase in creativity in PD, especially with the use of dopaminergic medications, appears to be a significant phenomenon and has recently been discussed in detail [2]. A number of cases have been reported in which patients with PD started producing artwork, in some cases in prodigious quantities, as the disease progressed. This has been seen not only with visual arts, but also with writing of various forms [2]. It is postulated that the combination of PD and therapy with dopaminergic agents is required for this creativity to emerge. In certain situations the drive to produce artwork appears to be part of a behavioral compulsion [3, 4], although obviously with a more concrete product, unlike with punding [5]. However, this does not apply to the present case, nor to many others [6], in which there is a specific goal of the activity.

It is possible that the improved resemblance of the patient’s image to the model could be explained by an improvement in his motor abilities with treatment, however, I believe that this is unlikely, as the most striking change is the improvement in the similarity of the content to the model. He clearly was able to paint straight lines in row B (center panel), however, the product bore only a general resemblance to his wife’s work (a landscape with hills and trees; right panel), as compared with his later pieces. Nor is it likely that there was a significant improvement in his technical skill with successive art classes – these classes only occurred every few months, and he was not painting at home in between.

One attractive hypothesis is that the improvement was related to an increase in visual attention with the increase in dopaminergic medication. Visual attention is known to be impaired in PD and may be improved by dopaminergic medications [7, 8]. While it has been broadly conceptualized that artistic ability is localized to the right hemisphere, it is now apparent that both hemispheres contribute to different aspects to the production of artistic work, and this may be a factor in the present case. It may be relevant that the patient’s symptoms were more marked on the right side of the body, and that attention to visual detail is localized to the left hemisphere, specifically the parietal cortex. Processing of local visual signals has been reported to be more impaired in patients with right-sided PD [9]. Thus it is possible that this function was impaired by dopamine deficiency, and was improved by replacement. Another mechanism that may have contributed is improved motor attention, which also localizes to the left parietal cortex [10]. It was also reported that the patient’s ability to perform mathematics improved as his dopaminergic medication was increased, suggesting that cognitive attention was the critical function. Serial neuropsychological evaluations would have been informative, however, these were not performed.

In general, it appears that dopaminergic agonists are typically responsible for behavioral changes in PD, thus it is of note that in the present case the dose of dopamine agonist was constant, while the levo-dopa dose was increased. This may suggest that what is reported here is not due to a change in behavior, but rather is due to improved dopaminergic functioning mediated by other cognitive mechanisms.