DBS, Dopamine, and Impulsivity

Dopamine-boosting drugs and deep brain stimulation (DBS) are the common avenues of approach in restoration of mobility in patients with Parkinson's disease. These two methods, however, are implicated in increased impulsivity, but in different ways. 

A group at the University of Arizona discovered these differences through the use of a computer game that presented each patient with two unfamiliar squiggles, one of which when selected would flash "Correct!". It was found that deep brain stimulation inhibits or interferes with a patient's tendency to pause and consider alternatives when faced with a difficult decision. Patients with DBS electrodes turned on made faster choices, but with the electrodes off, the same patients exhibited the normal tendency to consider alternatives. 

Dopamine, the group reported, inhibits a patient's ability to learn from negative experiences. In terms of the computer game, patients with elevated levels of dopamine had reduced tendencies to avoid choosing the incorrect squiggle. This effect of dopamine has been implicated in the incidence of repeated gambling without regards to losses in medicated Parkinson's patients.

I find this article interesting because it reminds the reader of how the body is truly an integrated system. One cannot affect one aspect of the body without affecting another aspect even to the slightest degree. I also find the insight that this article provides into decision making very interesting because it illustrates the range of effects that treatment options can have on a patient.

http://www.sciencemag.org/cgi/content/full/318/5850/553a